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NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C}
Definition statement
This subclass/group covers:

The chemical elements of hydrogen, halogen (fluorine, chlorine, bromine, iodine and astatine), oxygen, sulfur, phosphorus, silicon, nitrogen, boron, selenium, tellurium, and noble gases (helium, neon, argon, krypton, xenon and radon).

Compounds solely composed of any of the elements listed above.

Carbon and compounds of carbon with any of the elements listed above, with the proviso that said compounds cannot contain a carbon atom having direct bonding to another carbon atom, a carbon atom having direct bonding to a hydrogen atom or a halogen atom, or a carbon atom having direct bonding to a nitrogen atom by a single or double bond.

Compounds composed solely of one or more metal atoms and hydrogen.

Peroxides and salts of peroxyacids.

Magnesium, calcium, strontium, or barium sulfides or polysulfides.

Alkali metal sulfides or polysulfides.

Thiosulfates, dithionites and polythionates.

Compounds containing selenium or tellurium.

Azides, metal amides and nitrites.

Carbamic acid and salts thereof.

Binary compounds containing a metal and either N, C or P.

Salts of the oxyacids of halogen or phosphorus.

Compounds consisting only of carbon atoms, e.g. fullerenes, carbon nanotubes.

Phosgene and thiophosgene.

Compounds containing silicon such as silicates, silicon oxides or colloidal silica, e.g. dispersions, gels, hydroorganosols, organosols.

Compounds containing boron.

Substances having molecular sieve properties, but not having base-exchange properties.

Substances having a combination of molecular sieve and base-exchange properties, e.g. crystalline zeolites.

Synthesis, treatment or modification of any of the elements or compounds above by:

  • chemical means, i.e. chemical reaction;
  • physical means, e.g. concentration, dehydration, purification, separation, solidifying, granulation;
  • addition of a stabilizer or preservative; or
  • by the combination of chemical and physical means, with the proviso that the resultant product is proper for classification in this subclass.

Methods of preparing the following compounds, in general:

  • halides;
  • oxides or hydroxides;
  • sulphides or polysulfides;
  • sulfites;
  • sulphates;
  • nitrates; or
  • carbonates or bicarbonates.

Apparatus:

  • for preparation of sulfur trioxide or sulfuric acid by contact processes; or
  • for preparation of nitric oxide by catalytic oxidation of ammonia or oxidation of nitrogen.
Relationship between large subject matter areas

In Class C01, in the absence of an indication to the contrary, a compound is classified in the last appropriate subclass of this class. For example, lead oxide is classified in subclass C01G rather than in this subclass.

This subclass is a function oriented entry for the chemical elements and their compounds and does not cover the application or use of the elements and compounds under the subclass definition. For classifying such information other entries in IPC exist, for example:

  • Compounds or compositions for preservation of the bodies of humans, animals, plants, or parts thereof, e.g. disinfectants, pesticides, herbicides, as pest repellents or attractants, and as plant growth regulators are classified in subclass A01N.
  • Preparations for medical, dental, or toilet purposes are classified in subclass A61K.

Salts, adducts, or complexes formed between an inorganic compound of this subclass and an organic compound of class C07, are regarded as organic compounds and classified in class C07.

When a process produces multiple compounds only those which are intended or desired require classification and classification may be proper in multiple subclasses.

MULTIPLE CLASSIFICATION

Therapeutic activity of chemical compounds or medicinal preparations is further classified in subclass A61P.

Uses of cosmetics or similar toilet preparations are further classified in subclass A61Q.

Processes using enzymes or micro-organisms in order to:

  • liberate, separate or purify a pre-existing compound or composition, or to
  • treat textiles or clean solid surfaces of materials are further classified in subclass C12S.
References relevant to classification in this subclass
This subclass/group does not cover:
Treatment of inorganic materials to enhance their pigmenting or filling properties; Preparation of carbon black
Intentional preparation of carbon dioxide by a fermentation process or the use of an enzyme
Preparation of elements or inorganic compounds except carbon dioxide, by a fermentation process or the use of an enzyme
Production of non-metallic elements or inorganic compounds by electrolysis or electrophoresis

Examples of places where the subject matter of this class is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
Chemical or physical processes, e.g. catalysts, colloid chemistry; their relevant apparatus
Inorganic fertilisers
Organic chemistry
Alloys
Chemical libraries containing only inorganic compounds or inorganic materials
Methods of creating chemical libraries
Special rules of classification within this subclass/group

In this subclass, in the absence of an indication to the contrary, a compound or a process of making a compound appropriate for this subclass is classified in the last appropriate place.

This subclass provides for products which are intended or desired. When a process produces multiple compounds only those which are intended or desired require a classification. However, by-products can be given an additional classification if they or the processes for obtaining them are considered of interest for search.

Inorganic salts of a compound, unless specifically provided for elsewhere, are classified as that compound.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Base-exchange
The replacement of one cation absorbed on a material by another.
Binary compound
A compound containing and limited to two distinct chemical elements.
Direct bonding
Requires a bond between two adjacent atoms.
Inorganic compound
A compound devoid of a carbon atom and containing a non-metallic element, or a compound containing a carbon atom, and satisfying one of the following criteria: the compound cannot have a carbon atom having direct bonding to another carbon atom, or the compound cannot have direct bonding between a carbon atom and a halogen or hydrogen atom, or the compound cannot have direct bonding between a carbon and a nitrogen atom by a single or double bond. The following are exceptions to the above and are to be considered as inorganic compounds: compounds consisting of only carbon atoms, (e.g. fullerenes), cyanogen, cyanogen halides, cyanamide, phosgene, thiophosgene, hydrocyanic acid, isocyanic acid, isothiocyanic acid, fulminic acid, unsubstituted carbamic acid, and salts of the previously mentioned acids and which contain the same limitations as to a carbon atom.
Isomorphous zeolites
Compounds isomorphous to zeolites wherein the aluminum or silicon atoms in the framework are partly or wholly replaced by atoms of other elements, e.g. by gallium, germanium, phosphorus or boron.
Metal
Any element other than a non-metal.
Metal hydride
Compound containing only metal and hydrogen.
Molecular sieve
Materials (e.g. zeolitic, mesoporous) having cavities and channels which by their size allow some molecules to pass through, but prevent others.
Non-metal
The elements of hydrogen, carbon, halogen (fluorine, chlorine, bromine, iodine and astatine), oxygen, sulfur, phosphorus, silicon, nitrogen, boron, selenium, tellurium and noble gases (helium, neon, argon, krypton, xenon and radon).
Preparation
Covers synthesis, purification, separation, stabilisation, or use of additives, unless a separate place is provided in the classification scheme.
Zeolites
(i) Cystalline aluminosilicates with base-exchange and molecular sieve properties, having three dimensional, microporous lattice framework structure of tetrahedral oxide units; (ii) Compounds isomorphous to those of the former category, wherein the aluminium or silicon atoms in the framework are partly or wholly replaced by atoms of other elements, e.g. by gallium, germanium, phosphorus or boron.
Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it (separation of gases by physical means B01D) ; Purification of hydrogen (production of water gas or synthesis gas from solid carbonaceous material C10J; purifying or modifying the chemical compositions of combustible technical gases containing carbon monoxide C10K)
References relevant to classification in this group
This subclass/group does not cover:
Electrolytic production of hydrogen
Preparation of hydrogen by using micro-organisms or enzymes
Informative references
Attention is drawn to the following places, which may be of interest for search:
Aspects relating to hydrogen or synthesis gas generation processes
Details relating to the reactors used in the generation of hydrogen or synthesis gas
Separation of gases by physical means
Production of water gas or synthesis gas from solid carbonaceous material
Purifying or modifying the chemical compositions of combustible technical gases containing carbon monoxide
Vessels for containing or storing compressed, liquefied or solidified gases; fixed-capacity gas-holders; filling vessels with, or discharging from vessels, compressed liquefied, or solidified gases
Pipe-line systems; pipe-lines
Storing fluids in natural or artificial cavities or chambers in the earth
Special rules of classification within this group

In this group symbols of groups B01J 2208/00 and B01J 2219/00 should be added, for details relating to the reactors used in the generation of hydrogen or synthesis gas.

In groups C01B 3/12 to C01B 3/18 and in groups C01B 3/22 to C01B 3/586, symbols of group C01B 2203/00 should be added, for aspects relating to hydrogen or synthesis gas preparation processes.

{characterised by the uptaking medium; Treatment thereof}
Special rules of classification within this subclass/group

In all of the groups C01B 3/0026 to C01B 3/0084, the metallic storage materials may contain minor quantities of non-metals such as B, C, O, S, Se, Si; e.g. C01B 3/0036 "only containing iron and titanium" includes Fe-Ti compositions comprising a minor quantity of non-metals.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Rare-earth metal
one single metal or a combination of metals selected from the lanthanides, Sc or Y.
{Organic compounds; Solutions thereof}
Definition statement
This subclass/group covers:

Reversible uptake of hydrogen characterised by the uptaking medium being organic compounds, solutions thereof, e.g. metal organic frameworks

{only containing a rare earth metal and only one other metal}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
The "other metal"
is any other metal.
{Solid storage mediums characterised by their shape, e.g. pellets, sintered shaped bodies, sheets, porous compacts, spongy metals, hollow particles, solids with cavities, layered solids}
Definition statement
This subclass/group covers:

Reversible uptake of hydrogen characterised by the shape of the solid storage uptaking medium, e.g. hydrogen storage in glass beads amongst others.

{Preparation or purification of gas mixtures for ammonia synthesis}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Preparation or separation of ammonia.
Integration of a hydrogen producing process with ammonia synthesis.
by decomposition of inorganic compounds, e.g. ammonia { (C01B 3/0005 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Reversible uptake of hydrogen by an appropriate medium
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Decomposition (as opposed to reaction):
there is only one reactant involved.
by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents ( by electrolysis of water C25B 1/04)
References relevant to classification in this group
This subclass/group does not cover:
Electrolysis of water
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Reaction (as opposed to decomposition)
there are at least two reactants involved.
Silicon
is a metalloid and not a metal.
with metals
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Metals
only refers to pure metals or metal alloys. Metal hydrides or metal oxides are not covered by this term.
Silicon
is a metalloid and not a metal.
by reaction of water vapour with metals
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Metals
only refers to pure metals or metal alloys. Metal hydrides or metal oxides are not covered by this term.
Silicon
is a metalloid and not a metal.
by decomposition of gaseous or liquid organic compounds ( {C01B 3/0005 takes precedence } ; coking liquid carbonaceous materials C10B 55/00)
Definition statement
This subclass/group covers:

Production of hydrogen or gaseous mixtures containing hydrogen by decomposition of gaseous or liquid organic compounds or by an incomplete decomposition.

For example, a dehydrogenation specifically meant for the production of hydrogen will also be classified in this group.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Coking liquid carbonaceous materials
Synonyms and Keywords

In patent documents the following words "decomposition", "cracking" and "pyrolysis" are used as synonyms.

by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air
Special rules of classification within this group

If the documents does not specify the type of gaseous or liquid organic compound further and if it is not mentioned whether a catalyst is used, classify in C01B 3/32.

If it concerns a catalytic process, but if the type of gaseous or liquid organic compound is not further specified, then classify in C01B 3/38 and subgroups or in C01B 3/40.

{characterised by the catalyst}
Definition statement
This subclass/group covers:

Production of hydrogen or of gaseous mixtures containing hydrogen by catalytic reaction of gaseous or liquid organic compounds other than hydrocarbons with gasifying agents characterised by the catalyst.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Preparation and regeneration of catalysts
{Multi-step processes}
Definition statement
This subclass/group covers:

Multi-step process of hydrogen's or of gaseous mixtures containing hydrogen's production by catalytic reaction of hydrocarbons with gasifying agents, including also autothermal reforming.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Apparatus for autothermal reforming
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Catalytic multi-step process
A catalytic multi-step process, that generates a hydrogen containing gas from a hydrocarbon, is a process including at least one catalytic step.
{the catalyst being continuously externally heated}
Relationship between large subject matter areas

Chemical or physical processes in general and their relevant apparatus are classified in B01J

Special rules of classification within this group

This class is only to be allocated when the external heating is explicitly mentioned.

characterised by the catalyst
Definition statement
This subclass/group covers:

Production of hydrogen or of gaseous mixtures containing hydrogen by catalytic reaction of gaseous or liquid organic compounds other than hydrocarbons with gasifying agents characterised by the catalyst.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Preparation and regeneration of catalysts
{by selective and reversible uptake by an appropriate medium, i.e. the uptake being based on physical or chemical sorption phenomena or on reversible chemical reactions ( the appropriate mediums per se C01B 3/0005) }
Definition statement
This subclass/group covers:

This group covers separation or purification processes in which hydrogen or the hydrogen containing gas is removed from the gaseous mixtures

References relevant to classification in this group
This subclass/group does not cover:
Impurity and not hydrogen or the hydrogen containing gas is removed from the gaseous mixture.
Reversible uptake of hydrogen by an appropriate medium.
by contacting with solids; Regeneration of used solids { (C01B 3/508 takes precedence ) }
Definition statement
This subclass/group covers:

The removal of one or more impurities from hydrogen or a hydrogen containing gas from the gaseous mixture.

References relevant to classification in this group
This subclass/group does not cover:
Removal of hydrogen or hydrogen containing gas from the gaseous mixture.
Hydrogen isotopes; Inorganic compounds thereof prepared by isotope exchange, e.g. NH3 + D2 ---> NH2D + HD ( separation of isotopes B01D 59/00 ; other chemical reactions to form compounds of hydrogen isotopes, see the relevant groups for hydrogen compounds in class C01)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Separation of isotopes
Other chemical reactions to form compounds of hydrogen isotopes
Water
Definition statement
This subclass/group covers:

This group only covers documents directed to the preparation of water, water being the product.

References relevant to classification in this group
This subclass/group does not cover:
Arrangement of installations for producing fresh water, e.g. by evaporation and condensation of sea water.
B063J1/00
Treatment of water
Fuel cell (production of electricity with water as side product)
Hydrides of metals {including fully or partially hydrided metals, alloys or intermetallic compounds ( use of some thereof for reversible sorption of hydrogen C01B 3/0005 , C01B 3/508) ; Compounds containing at least one metal-hydrogen bond, e.g. (GeH3)2S, SiH GeH} ; Monoborane or diborane; Addition complexes thereof ( higher hydrides of boron, substituted hydrides of boron C01B 35/00)
Definition statement
This subclass/group covers:

This group covers documents, in which metal hydrides are claimed per se and documents, in which the preparation of metal hydrides is disclosed.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Reversible uptake of hydrogen by an appropriate medium
Higher hydrides of boron than monoborane or diborane, substituted hydrides of boron
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Metal hydride
Compound containing only metal or metal alloy and hydrogen.
Halogens; Halogen acids ( oxyacids C01B 11/00)
References relevant to classification in this group
This subclass/group does not cover:
Oxyacids of halogens and salts thereof
C01B11/00D
General methods of preparing halides ( particular individual halides, see the relevant groups in C01B to C01G according to the element combined with the halogen; electrolytic production of inorganic compounds C25B)
References relevant to classification in this group
This subclass/group does not cover:
Electrolytic production of inorganic compounds
Special rules of classification within this group

Particular individual halides according to the element combined with the halogen are classified in the relevant groups C01B to C01G.

Oxides or oxyacids of halogens; Salts thereof
Definition statement
This subclass/group covers:

Oxides or oxyacids of halogens or salts thereof when claimed as such and the preparation thereof.

Oxygen; Ozone; Oxides or hydroxides in general
Definition statement
This subclass/group covers:

The preparation of oxygen, ozone, oxides and hydroxides.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Use or ozone for disinfecting
Preparation of oxygen ( { enrichment of a gaseous mixture, in particular air, in oxygen or separation of oxygen from a gaseous mixture by an adsorption process B01D63/03} ; by liquefying F25J)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Enrichment of a gaseous mixture, in particular air, in oxygen or separation of oxygen from a gaseous mixture by an adsorption process
B01D63/03
Enrichment of a gaseous mixture, in particular air, in oxygen or separation of oxygen from a gaseous mixture by liquefying
{Purification or separation processes}
Definition statement
This subclass/group covers:

Purification and separation processes related to the production of oxygen

Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
Special rules of classification within this group

In groups C01B 13/0229 to C01B 13/0288, additional features relating to the purification or separation processes are indexed with symbols chosen from C01B 2210/0026 to C01B 2210/0098.

{Combined chemical and physical processing}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
Chemical or physical processes, e.g. catalysts, colloid chemistry; their relevant apparatus
Special rules of classification within this group

In this group, processing steps are also classified with symbols chosen from C01B 2210/0001 to C01B 2210/0025.

Preparation of ozone
Special rules of classification within this group

When ozone is produced by generation of a plasma, the document is classified in C01B 13/10 and not in C01B 13/11.

by electric discharge
Relationship between large subject matter areas

Process for preparation of ozone and its apparatus are classified in C01B 13/11 subgroups.

Devices for providing corona discharge are classified in H01T 19/00 subgroups.

Process for preparation of ozone by ultra-violet light, the apparatus is also classified in B01J 19/123

Special rules of classification within this group

When ozone is produced by generation of a plasma, the document is classified in C01B 13/10 and not in C01B 13/11.

In groups C01B 13/11 and C01B 13/115, additional features relating to the preparation of ozone by electrical discharge are classified with symbols chosen from C01B 2201/00 to C01B 2201/90.

Methods for preparing oxides or hydroxides in general (particular individual oxides or hydroxides, see the relevant groups of subclasses C01B to C01G or C25B, according to the element combined with the oxygen or hydroxy group)
Definition statement
This subclass/group covers:

Methods for preparing (hydr)oxides in general, not specific to a particular (hydr)oxide

Relationship between large subject matter areas

Particular individual oxides or hydroxides are classified in the relevant groups of subclasses C01B to C01G or C25B, according to the element combined with the oxygen or hydroxy group

References relevant to classification in this group
This subclass/group does not cover:
Generic features dealing with the preparation of (hydr)oxides of sodium, potassium or alkali metals
Generic features dealing with the preparation of (hydr)oxides of metals not covered by C01B, C01D or C01F
Preparation of (hydr)oxides by electrolysis
Special rules of classification within this group

Contrary to the strict interpretation of the wording of the groups of C01 does this group dealing with the preparation of (hydr)oxides also comprise the after-treatment (C01B 13/145) and the purification (C01B 13/16).

{After-treatment of oxides or hydroxides, e.g. pulverising, drying, decreasing the acidity}
References relevant to classification in this group
This subclass/group does not cover:
The after treatment of oxides for improving the pigmenting or filling properties:
Purification
Definition statement
This subclass/group covers:

All methods for purification of oxides or hydroxides in general

References relevant to classification in this group
This subclass/group does not cover:

The purification of specific oxides (see the relevant class of C01D-C01G), e.g.:

Of aluminium (hydr)oxides:
Of calcium, strontium or barium oxides:
Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
Special rules of classification within this group

The purity of compounds in solid compounds in C01 is also covered by the group C01P 2006/80

by thermal decomposition of compounds, e.g. of salts or hydroxides
Definition statement
This subclass/group covers:

The decomposition by application of heat without the addition of other reactants. Starting solutions can be sprayed but the obtained dried precursor is subsequently in a separate step decomposed by heat.

References relevant to classification in this group
This subclass/group does not cover:
The one-step conversion of sprayed or atomized solutions
by oxidation of elements in the gaseous state; by oxidation or hydrolysis of compounds in the gaseous state
Definition statement
This subclass/group covers:

The oxidation or hydrolysis of metal (oxy)halides only.

References relevant to classification in this group
This subclass/group does not cover:
Oxidation or hydrolysis of metal-organic compounds (e.g. alkoxides)
by oxidation or hydrolysis of elements or compounds in the liquid or solid state {or in non-aqueous solution, e.g. sol-gel process}
Definition statement
This subclass/group covers:

The oxidation or hydrolysis of (e.g. organic) metal compounds, in pure form ('in the liquid state' in subgroup C01B13/36C) or dissolved in a non-aqueous (e.g. alcohol) solution ('in solution'). The 'sol-gel process' is classified in here.

References relevant to classification in this group
This subclass/group does not cover:
Precipitation reactions in aqueous solutions:
by oxidation or hydrolysis of sprayed or atomised solutions
References relevant to classification in this group
This subclass/group does not cover:
Processes whereby after spraying a precursor is obtained (e.g. a salt) which is subsequently decomposed inot the oxide in a separate furnace:
by precipitation reactions in {aqueous} solutions { (C01B 13/328 takes precedence ) }
Definition statement
This subclass/group covers:

Precipitation reactions, e.g. from a metal salt by adding a base like NaOH or NH3

References relevant to classification in this group
This subclass/group does not cover:

Groups comprises reactions in non-aqueous solutions. Hydrolysis of (organic) starting materials in e.g. alcohols by the sol-gel process, see C01B 13/32.

{Mixtures of oxides or hydroxides by precipitation}
Definition statement
This subclass/group covers:

Mixtures of oxides or hydroxides including mixed (hydr)oxides, i.e. plural metal oxides or hydroxides and also mixtures of metal oxides and hydroxides

{by hydrothermal processing}
Definition statement
This subclass/group covers:

Processes whereby a pressure above one bar is realised by heating an aqueous solution above 100°C in a closed container (autoclave).

Synonyms and Keywords
Closed reaction container
autoclave
Peroxides; Peroxyhydrates; Peroxyacids or salts thereof; Superoxides; Ozonides
Definition statement
This subclass/group covers:

Peroxides, peroxyhydrates, peroxyacids and salts thereof, superoxides and ozonides when claimed as such and the preparation processes thereof.

Sulfur; Compounds thereof
Definition statement
This subclass/group covers:

Compositions consisting of elemental sulfur or of sulfur compounds as far as not classified in groups following C01B 17/98 according to the other elements (like transition metals) present. This groups includes preparations of such compositions as well as after-treatments in general, thus in so far these are not limited to one specific application. Also included are apparatus specially adapted to the preparation.

Preparation of sulfur; Purification
Definition statement
This subclass/group covers:

Preparation of elemental sulfur only.

{Separation of sulfur from gases}
References relevant to classification in this group
This subclass/group does not cover:
As part of the Claus process:
Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
{Melting}
Definition statement
This subclass/group covers:

e.g. block melting

{Purification, e.g. degassing}
Definition statement
This subclass/group covers:

All types of removal of all kind of impurities irrespective the source of the sulfur.

References relevant to classification in this group
This subclass/group does not cover:
Purification of sulfur obtained from materials comprising elemental sulfur:
Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
{Converting into particles, e.g. by granulation, milling}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Granulation in general
{from non-gaseous sulfur compounds other than sulfides or materials containing such sulfides}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Sulfur from H2S or H2S-containing gases:
Sulfur from SO2 or SO2-containing gases:
Recovery of sulfur from material containing elemental sulfur, e.g. luxmasses {or sulfur containing ores} ; Purification {of the recovered sulfur}
References relevant to classification in this group
This subclass/group does not cover:
Purification of sulfur in general or obtained by other methods:
from gaseous sulfur compounds including gaseous sulfides
Definition statement
This subclass/group covers:

All process whereby the sulfur source is a gaseous sulfur compound, e.g. H2S, SO2

Informative references
Attention is drawn to the following places, which may be of interest for search:
Catalytic removal of sulfur compounds from gas streams in general:
{by processes comprising a dry catalytic conversion of hydrogen sulfide-containing gases, e.g. the Claus process}
Definition statement
This subclass/group covers:
  • This subgroup covers also other processes than the Claus process.
  • This group includes also specific steps not classifiable in the subgroups C01B 17/0408 to C01B 17/0469 according to the characterising features of these steps, e.g. heat exchangers not being part of a combustion furnace.
  • Features which relate to several separate steps of the Claus process are classified in C01B 17/0404, e.g. parts of flow sheets (like gas lines connecting separate steps).
References relevant to classification in this group
This subclass/group does not cover:
Obtaining sulfur from gaseous compounds by wet processing:
Processes for the removal of H2S from gas streams whereby the H2S is present as an impurity:
Special rules of classification within this group
  • Features relating to specific steps of the Claus process are classified in the subgroups C01B 17/0408-C01B 17/0456.
  • Specific steps not classifiable in the subgroups according to the characterising features of these steps (e.g. heat exchangers not being part of a combustion furnace) are classified in C01B 17/0404.
  • Features which relate to several separate steps of the Claus process are classified in C01B 17/0404, e.g. details of flow sheets (like gas lines connecting separate steps).
{Pretreatment of the hydrogen sulfide containing gases}
Definition statement
This subclass/group covers:

All kind of operations applied to the feed gas, e.g. concentration by absorption, adsorption or purification (removal of non-sulfur components).

{characterised by the combustion step}
Definition statement
This subclass/group covers:

E.g. the thermal step of the Claus process.

{Combustion reactors}
Definition statement
This subclass/group covers:

Only constructional features of the reactor, including waste heat boilers and the like connected therewith.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Reactors in general:
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Combustion reactor
thermal Claus furnace
{Multistage combustion}
Definition statement
This subclass/group covers:

Only multi-combustion in two separate furnaces.

Special rules of classification within this group

Two oxidizer gas flows to one single reactor is classified in C01B 17/0413 (or C01B 17/0417 when it concerns the reactor).

{Catalytic converters}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Chemical or biological purification of engine exhaust gases
Reactors in general
Exhaust apparatus having means for purifying exhaust gases
{Catalyst compositions}
Definition statement
This subclass/group covers:

The compositions are considered to include supports.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Catalytic compositions in general:
Special rules of classification within this group

Mechanical adaptations of the catalytic reactor for comprising the catalyst are classified in C01B 17/043.

{at least one catalyst bed operating below the dew-point of sulfur}
Definition statement
This subclass/group covers:
  • All those processes whereby sulfur (liquid or solid) remains in or at the catalyst. This group comprises also measures for the regeneration of the sulfur-loaded catalyst.
  • E.g. CBA (Cold Bed Absorption), MCRC (Maximum Claus Recovery Concept), Sulfreen or Maxisulf.
  • Clinsulf can also be operated at sub-dew point conditions.
{in a moving bed}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Moving bed
e.g. fluidized bed
{Separation of the obtained sulfur}
Definition statement
This subclass/group covers:

Measures dealing with the separation of the elemental sulfur after one or more of the separate steps of e.g. the Claus process.

References relevant to classification in this group
This subclass/group does not cover:
Purification of the separated sulfur
C01B17/04P
{Process control; Start-up or cooling-down procedures of the Claus process}
Definition statement
This subclass/group covers:

E.g. adjustment of ratio of gas stream components.

{the hydrogen sulfide-containing gas being a Claus process tail gas}
Definition statement
This subclass/group covers:

Those processes whereby the tail gas from a Claus process plant are reused for obtaining sulfur, e.g. by concentration of H2S or reduction of SO2 present in the tail gas.

References relevant to classification in this group
This subclass/group does not cover:
Removal of sulfur compounds from Claus tail gases without obtaining elemental sulfur:
{without intermediate formation of sulfur dioxide}
Definition statement
This subclass/group covers:
  • These processes are also indicated as selective oxidation or direct oxidation of H2S.
  • E.g. 'Superclaus'-processes comprising thermal and catalytic Claus steps combined with a selective oxidation step.
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Without intermediate formation of sulfur
selective oxidation or direct oxidation
{Catalyst compositions}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Catalysts in general:
{at least one catalyst bed operating below the dew-point of sulfur}
Definition statement
This subclass/group covers:

E.g. Clauspol process.

References relevant to classification in this group
This subclass/group does not cover:
Subdew-point process as part of the Claus process:
{by reaction of sulfur dioxide or sulfur trioxide containing gases with reducing agents other than hydrogen sulfide}
Definition statement
This subclass/group covers:

Reaction of SO2 or SO3 with all kind of reducing agents, gaseous, liquid or solid.

{with hydrocarbons or mixtures containing them}
Definition statement
This subclass/group covers:

Reduction of SO2, e.g. with natural gas.

{by dissociation of hydrogen sulfide into the elements}
Special rules of classification within this group

Classification is also accomplished in C01B 3/04 because of the produced hydrogen.

by wet processes
Definition statement
This subclass/group covers:
  • This group comprises all processes comprising a liquid step, indpependent of the character of the liquid.
  • E.g. iron chelate processes.
References relevant to classification in this group
This subclass/group does not cover:
Removal of sulfur compounds from gases without obtaining elemental sulfur
from non-gaseous sulfides or materials containing such sulfides, e.g. ores
Informative references
Attention is drawn to the following places, which may be of interest for search:
Preparation of sulfur from sulfates
Hydrogen sulfides
Definition statement
This subclass/group covers:

Preparation, separation or purification of binary hydrogen-sulfur compounds.

{Preparation by reduction of oxidic sulfur compounds}
Informative references
Attention is drawn to the following places, which may be of interest for search:
The preparation of elemental sulfur from SO2 or SO3
{Separation}
Definition statement
This subclass/group covers:

Recovery of H2S from gas streams.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus for separation in general
{Purification}
Definition statement
This subclass/group covers:

Removal of all kind of impurities (gaseous, liquid or solid) from H2S.

References relevant to classification in this group
This subclass/group does not cover:
The removal of large amounts of components qualified as impurities is regarded to represent a separation of H2S from that gas stream (e.g. 70% impurity, 30% H2S) and is classified in
Hydrogen polysulfides
Definition statement
This subclass/group covers:

All compounds H2S1+x, wherein x>0

Methods for preparing sulfides or polysulfides, in general ( ammonium sulfides or polysulfides C01C ; sulfides or polysulfides of metals, other than alkali metals, magnesium, calcium, strontium and barium, see the relevant groups of subclasses C01F or C01G , according to the metal )
Definition statement
This subclass/group covers:

Methods for preparing sulfided or polysulfides in general, not specific to the chemical nature of the (poly)sulfide.

Relationship between large subject matter areas
  • Ammonium (poly)sulfides: C01C 1/20
  • Methods relating to one specific metal sulfide are classified according to the metal: C01D, C01F or C01G
Special rules of classification within this group

All documents in this group and its subgroups are classified in the C01P subgroups

Alkali metal sulfides or polysulfides
Special rules of classification within this group

All documents in this group and its subgroups are classified in the C01P subgroups

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Polysulfides
all compounds Me2S1+x, with x>0
Polysulfides of sodium or potassium
Definition statement
This subclass/group covers:

All compounds Me2S1+x, with x>0, Me=Na,K

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Polysulfides
All compounds Me2S1+x, with x>0, Me=Na,K
Sulfides or polysulfides of magnesium, calcium, strontium, or barium
Informative references
Attention is drawn to the following places, which may be of interest for search:
Sulfates of these metals
Sulfites of these metals:
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Polysulfides:
all compounds MeS1+x, with x>0
Compounds containing sulfur and halogen, with or without oxygen
Special rules of classification within this group

All documents in this group and its subgroups are indexed according to the C01P-scheme

Sulfur dioxide; Sulfurous acid
Definition statement
This subclass/group covers:

SO2 and H2SO3

Preparation of sulfur dioxide
Definition statement
This subclass/group covers:

Process for the preparation and apparatus specifically adapted therefor.

{of ammonium sulfates ( of ammonium sulfates containing sulfuric acid solutions C01B 17/585) }
References relevant to classification in this group
This subclass/group does not cover:
Starting from ammonium sulfates containing sulfuric acid
by roasting sulfides (C22B 1/00 takes precedence )
References relevant to classification in this group
This subclass/group does not cover:
Preliminary treatment of ores
by burning elemental sulfur
Definition statement
This subclass/group covers:

All combustion processes sulfur, as solid, liquid or gas

Informative references
Attention is drawn to the following places, which may be of interest for search:
Burners in general
Special rules of classification within this group

Processes comprising the combustion of sulfur followed by the oxidation of SO2 into SO3 are classified according to the step which makes the contribution over the prior art. A (further not specified) burning of sulfur with a specific oxidation catalyst is classified in C01B 17/78. A well defined burning step with a common oxidation into SO3 is classified in C01B 17/54. In case both steps make the invention is the document classified in both groups.

Separation; Purification
Definition statement
This subclass/group covers:

Preparation of sulfur dioxide by separation, purification.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
Chemical or physical processes, e.g.sulfur removal form a waste gas
Special rules of classification within this group

See also C01B 17/60

Isolation of sulfur dioxide from gases
Special rules of classification within this group

See also C01B 17/56

Methods of preparing sulfites in general ( particular individual sulfites, see the relevant groups of subclasses C01B to C01G , according to the cation )
Definition statement
This subclass/group covers:

Methods of preparing sulfites in general and not specific to the chemical nature of the sulfite.

References relevant to classification in this group
This subclass/group does not cover:
Specific sulfites are classified according to the metal
{metabisulfites or pyrosulfites}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Metabisulfites or pyrosulfites
S 2O 52-
Thiosulfates; Dithionites; Polythionates
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Thiosulfates
S 2O 32-
Ithionites (=hydrosulfites)
S 2O 42-
Dithionites {or hydrosulfites (S204 2-) }
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Dithionites (=hydrosulfites)
S 2O 42-
Sulfur trioxide; Sulfuric acid
Definition statement
This subclass/group covers:

All features in relation to SO3 or H2SO4 not classifiable in the subgroups of C01B 17/69.

Preparation
Definition statement
This subclass/group covers:

All documents dealing with preparative features not classifiable in the subgroups of C01B 17/74.

by contact processes
Definition statement
This subclass/group covers:

All catalytic processes for the oxidation of SO2 into SO3. This group comprises features not classifiable in the subgroups of C01B 17/76.

In the contact processes the contact is the catalyst (a solid), it's then a gas/gas reactions in presence of a solid.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes and apparatus in general for separation
Chemical or physical processes
Multi-stage SO3-conversion
Definition statement
This subclass/group covers:

All conversion which includes more than one catalyst bed ('contact'), irrespective of whether they are present in one convertor or in several convertors.

{with intermediate absorption}
Definition statement
This subclass/group covers:

All processes where in addition to the final absorber at least one other SO3-absorption is present between the catalytic beds.

{Recovery from spent acids containing metallic ions, e.g. hydrolysis acids, pickling acids ( obtaining sulfur dioxide as an intermediate in sulfur trioxide recovery from sulfates, e.g. iron sulfates C01B 17/501 , from spent acids C01B 17/58) }
Definition statement
This subclass/group covers:

The presence in the starting solution of metallic ions is essential

References relevant to classification in this group
This subclass/group does not cover:
From sulfates whereby SO2 is obtained
From spent acids
{by dialysis}
Special rules of classification within this group

Removal of some specific impurities are classified in C01B 17/905-C01B 17/908.

{by liquid-liquid extraction}
Special rules of classification within this group

Removal of some specific impurities are classified in C01B 17/905-C01B 17/908.

{by ion-exchange}
Relationship between large subject matter areas

Separating processes in general involving the treatment of liquids with ion exchange materials as adsorbents are classified in B01D15/04

Special rules of classification within this group

Removal of some specific impurities are classified in C01B 17/905-C01B 17/908.

{Removal of organic impurities}
Definition statement
This subclass/group covers:

Purification of sulfuric acid in which the impurity is present.

Special rules of classification within this group

See also C01B 17/92 in case of a mixture of acid and organic compounds.

Methods for the preparation of sulfates in general ( particular individual sulfates, see the relevant groups of subclasses C01B to C01G , according to the cation )
Definition statement
This subclass/group covers:

Methods for the preparation of sulfates in general, and not specific to the chemical nature of the sulfate.

References relevant to classification in this group
This subclass/group does not cover:
Processes or apparatus for the preparation of specific sulfates are classified according to the metal ion
{Pyrosulfates}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Pyrosulfate
2O 72-
Other compounds containing sulfur and oxygen ( persulfuric acids C01B 15/06 ; persulfates C01B 15/08)
References relevant to classification in this group
This subclass/group does not cover:
Persulfuric acid
Persulfates
Selenium; Tellurium; Compounds thereof ( phosphorus compounds C01B 25/14)
References relevant to classification in this group
This subclass/group does not cover:
Compounds containing also phosphorous
Special rules of classification within this group

All documents in this group and its subgroups (so C01B 19/00 - C01B 19/04) are classified with symbols chosen from C01P-subgroups

{Compounds containing, besides selenium or tellurium, more than one other element, with -O- and -OH not being considered as anions}
Definition statement
This subclass/group covers:

The compounds classified in this group do have more than one element other than Se or Te, O and H not taken into account. The compounds with only one other element do find classification in the subgroups of this group.

References relevant to classification in this group
This subclass/group does not cover:
Compounds of Se or Te with only one other element, O and H not taken into acount
{Tellurides or selenides of metals (C01B 19/002 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Compounds of Se or Te with more than one metal or other element, except O or H
Elemental selenium or tellurium
Definition statement
This subclass/group covers:

This group comprises also mixtures of Se and Te.

Binary compounds {including binary selenium-tellurium compounds (C01B 19/004 , C01B 19/005 , C01B 19/007 take precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Oxides or hydroxides of Se or Te
Halides of Se or Te
Tellurides or selenides of metals
Nitrogen; Compounds thereof
Definition statement
This subclass/group covers:

All compounds of nitrogen insofar they are not classified according to the last place rule to groups after C01B 21/50, namely in C01C, C01D, C01F or C01G.

Preparation of nitrogen (by decomposition of ammonia {C01B 3/047} )
Definition statement
This subclass/group covers:

Obtaining nitrogen by preparation or synthesis.

References relevant to classification in this group
This subclass/group does not cover:
Obtaining nitrogen by decomposition of ammonia
Informative references
Attention is drawn to the following places, which may be of interest for search:
Separation of nitrogen from gas mixtures, e.g. air
Purification or separation of nitrogen ( by liquefying F25J)
Relationship between large subject matter areas

All purifications or gas separations involving a liquefaction step: F25J

References relevant to classification in this group
This subclass/group does not cover:
Obtaining nitrogen by liquefaction or rectification
{Purification or separation processes}
References relevant to classification in this group
This subclass/group does not cover:
Obtaining oxygen by separation
Informative references
Attention is drawn to the following places, which may be of interest for search:
Gas separation in general:
Special rules of classification within this group

During classification are additional features classified using the groups C01B 2210/00-M91B210/00W90. Example of such features is the type of impurity removed (C01B 2210/0043).

{Chemical processing only}
Definition statement
This subclass/group covers:

Those processes comprising only chemical methods as e.g. specified by the subgroups C01B 21/0416- C01B 21/0427.

{by oxidation}
Definition statement
This subclass/group covers:

Chemical oxidation processes such as the removal of hydrogen by addition of oxygen to the feed gas. The impurity is oxidized.

{by reduction}
Definition statement
This subclass/group covers:

Chemical reduction processes such as the removal of oxygen by addition of a reducing agent, like hydrogen. The impurity is reduced.

{Physical processing only}
Definition statement
This subclass/group covers:

Those processes comprising only physical methods as e.g. specified by the subgroups C01B 21/0438- C01B 21/0488.

{by making use of membranes}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Membranes as such:
Synonyms and Keywords
Pressure swing absorption
PSA
{characterised by the adsorbent}
References relevant to classification in this group
This subclass/group does not cover:
Solid sorbents compositions per se
{Temperature swing adsorption}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
TSA
temperature swing adsorption
{Combined chemical and physical processing}
Definition statement
This subclass/group covers:

All processes comprising a sequence of steps each covered by the groups C01B 21/0411-C01B 21/0488

Special rules of classification within this group

All processes comprising a sequence of steps each covered by the groups C01B 21/0411-C01B 21/0488 do get this symbol C01B 21/0494 in combination with symbols for the individual steps chosen from C01B 2210/00-C01B 2210/0025. Additional treatment steps which are the result of the main treatment operation are not recognised as separate step (e.g. removal of water by an adsorption step after the reductive treatment with hydrogen for the removal of oxygen during which the water is formed).

Groups for the type of impurity removed (C01B 2210/0043) are always applied as complete as possible.

Binary compounds of nitrogen with metals, with silicon, or with boron, {or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron} ( azides C01B 21/08)
References relevant to classification in this group
This subclass/group does not cover:
Azides
Shaped bodies made of nitrides:
C04B 35/58 and subgroups
Special rules of classification within this group
  • A document specifying a series of binary compounds (e.g. more than 5) is classified in this group with groups chosen from C01B 21/06-C01B 21/076 for the individual compounds.
  • All documents of this group and its subgroups up to C01B 21/0768 are fully classified with the symbols chosen from C01P subgroups.
{with two or more other elements chosen from metals, silicon or boron}
Definition statement
This subclass/group covers:

E.g. mixed nitrides.

{Binary compounds of nitrogen with carbon}
Definition statement
This subclass/group covers:

All compounds between carbon and nitrogen, CxNy

{with gallium, indium or thallium}
Relationship between large subject matter areas

Preparing single crystals of GaN: C30B

{Preparation by direct nitridation of elemental boron}
Definition statement
This subclass/group covers:

Nitridation can take place by any nitrogen source, e.g. nitrogen, ammonia.

{Preparation by carboreductive nitridation}
Definition statement
This subclass/group covers:

Processes whereby the boron oxide source is reduced with a carbon containing material like graphite or active carbon, carbon being elemental or not

{Preparation by pyrolysis of boron and nitrogen containing compounds}
Definition statement
This subclass/group covers:

Processes in which the nitrogen is provided by the precursor, although the reaction can take place in an ammonia or nitrogen containing atmosphere.

{After-treatment, e.g. grinding, purification ( transformation of hexagonal into cubic or wurtzitic boron nitride C04B 35/5831) }
References relevant to classification in this group
This subclass/group does not cover:
Transformation of hexagonal into cubic or wurtzitic BN
{Preparation by direct nitridation of silicon}
Definition statement
This subclass/group covers:

Nitridation can take place by any nitrogen source, e.g. nitrogen, ammonia.

{Preparation by carboreductive nitridation}
Definition statement
This subclass/group covers:

Proce sses whereby the silicon oxide source is reduced with a carbon containing material like graphite or active carbon, carbon being elemental or not.

{Preparation by direct nitridation of aluminium}
Definition statement
This subclass/group covers:

Nitridation can take place by any nitrogen source, e.g. nitrogen, ammonia.

{Preparation by carboreductive nitridation}
Definition statement
This subclass/group covers:

Processes whereby the aluminium oxide source is reduced with a carbon containing material like graphite or active carbon, carbon being elemental or not.

{Preparation by direct nitridation of titanium, zirconium or hafnium}
Definition statement
This subclass/group covers:

Nitridation can take place by any nitrogen source, e.g. nitrogen, ammonia.

{Preparation by carboreductive nitridation}
Definition statement
This subclass/group covers:

Processes whereby the metal oxide source is reduced with a carbon containing material like graphite or active carbon, carbon being elemental or not.

{Preparation by pyrolysis of nitrogen containing titanium, zirconium or hafnium compounds}
Definition statement
This subclass/group covers:

Processes whereby the nitrogen is provided by the precursor although these processes may be accomplished in an ammonia or nitrogen atmosphere.

Compounds containing nitrogen and non-metals {and optionally metals} (C01B 21/06 , C01B 21/08 take precedence )
References relevant to classification in this group
This subclass/group does not cover:
Binary compounds of nitrogen with metals, Si or B or compounds of nitrogen with more than one metal, Si or B
Hydrazoic acid, Azides or halogen azides
Special rules of classification within this group

All documents of this group and its subgroups up to C01B 21/0828 are fully classified with the symbols chosen from C01P subgroups

{Nitrosyl fluoride}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Nitrosyl fluoride
NOF
{Nitrosyl chloride}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Nitrosyl chloride
NOCl
{Metal imides or amides ( silicon imides or amides C01B 21/087) }
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Metal amide
MeNH2
Metal imide
MeNH
{of alkali metals}
Definition statement
This subclass/group covers:

E.g. lithium amide: LiNH2; lithium imide: Li2NH

{Imidodisulfonic acid; Nitrilotrisulfonic acid; Salts thereof}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Imidodisulfonic acid
HSO3NHSO3H
Nitrilotrisulfonic acid
N(SO3H)3
Amidosulfonic acid; Salts thereof
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Amidosulfonic acid
NH2HSO3
Carbamic acid {or thiocarbamic acid} ; Salts thereof
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Carbamic acid
H2NCOOH
Monothiocarbamic
H2NCOSH or H2NCSOH
Dithiocarbamic acid
H2NCS2H
Ammonium carbamate
H2NCOONH4
Hydroxylamine; Salts thereof
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Hydroxylamine:
NH2OH
Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
Definition statement
This subclass/group covers:

All oxides of nitrogen and their acids

{Nitric anhydride (N2O5) (C01B 21/203 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Processes using a plasma or electric discharge
Nitrous oxide (N2O) { (C01B 21/203 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Processes using a plasma or electric discharge
Nitric oxide (NO) { (C01B 21/203 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Processes using a plasma or electric discharge
{characterised by the catalyst}
Relationship between large subject matter areas

Catalysts in general: B01J

Methods for the preparation of nitrates in general ( particular individual nitrates, see the relevant groups of subclasses C01B to C01G , according to the cation )
Definition statement
This subclass/group covers:

Methods for the preparation of nitrates in general and not specific to the chemical nature of the nitrate.

References relevant to classification in this group
This subclass/group does not cover:
Methods relating to one specific metal nitrate are classified according to the cation
Nitrous acid; Salts thereof
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Nitrous acid
HNO2
Noble gases; Compounds thereof (liquefying F25J; { noble gases obtained by rectification F25J 3/028} )
Relationship between large subject matter areas

Liquefaction or liquefying in general: F25J

References relevant to classification in this group
This subclass/group does not cover:
Obtaining noble gases by processes including a liquefying step
{Purification or separation processes of noble gases}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Gas separation in general
Special rules of classification within this group

During classification are additional features classified using the groups C01B 2210/00-M91B210/00W90. Example of such features is the type of impurity removed (C01B 2210/0043).

{Chemical processing only}
Definition statement
This subclass/group covers:

Those processes comprising only chemical methods not covered by the subgroups C01B 23/0021-C01B 23/0031.

{by oxidation}
Definition statement
This subclass/group covers:

Chemical oxidation processes such as removal of hydrogen by addition of oxygen to the feed gas. The impurity is oxidized.

{by reduction}
Definition statement
This subclass/group covers:

Chemical reduction processes such as the removal of oxygen by addition of a reducing agent, like hydrogen. The impurity is reduced.

{Physical processing only}
Definition statement
This subclass/group covers:

Those processes comprising only physical methods as e.g. specified by the subgroups C01B 23/0042-C01B 23/0089.

{by making use of membranes}
References relevant to classification in this group
This subclass/group does not cover:
Membranes as such:
Synonyms and Keywords
Pressure swing absorption
PSA
{characterised by the adsorbent}
References relevant to classification in this group
This subclass/group does not cover:
Solid sorbent compositions
{Temperature swing adsorption}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
TSA
temperature swing adsorption
{Combined chemical and physical processing}
Definition statement
This subclass/group covers:

All processes comprising a sequence of steps each covered by the groups C01B 23/0015-C01B 23/0089

Special rules of classification within this group

All processes comprising a sequence of steps each covered by the groups C01B 23/0015-C01B 23/0089 do get this symbol C01B 23/0094 in combination with symbols for the individual steps chosen from C01B 2210/00-C01B 2210/0025. Additional treatment steps which are the result of the main treatment operation are not recognised as separate step (e.g. removal of water by an adsorption step after the reductive treatment with hydrogen for the removal of oxygen during which the water is formed).

Groups for the type of impurity removed (C01B 2210/0043) or the type of noble gas obtained (C01B 2210/0029) are always applied as complete as possible.

Phosphorus; Compounds thereof ( {C01B 6/00} , C01B 21/00 , C01B 23/00 take precedence; perphosphates C01B 15/16)
Definition statement
This subclass/group covers:

Elemental phosphorus and compounds thereof. Included in this group are processes and apparatus used in obtaining these products. Also included in this group are processes and apparatus for after-treatments in general.of phosphorous compounds and not related to a specific phosphorous compound.

References relevant to classification in this group
This subclass/group does not cover:
Hydrides of metals and phosphorus
Compounds containing nitrogen and phosphorus
Compounds containing noble gases and phosphorus
Perphosphates
Informative references
Attention is drawn to the following places, which may be of interest for search:
Phosphates for prostheses or for coating prostheses
{Stabilisation (C01B 25/04 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Purification of phosphorus
Oxyacids of phosphorus; Salts thereof ( peroxyacids or salts thereof C01B 15/00)
References relevant to classification in this group
This subclass/group does not cover:
Peroxyacids of phosphorus or salts thereof
Special rules of classification within this group
Purification; Stabilisation; Concentration ( purification concomitant with preparation C01B 25/22 ; preparation involving solvent-solvent extraction C01B 25/46)
References relevant to classification in this group
This subclass/group does not cover:
Purification concomitant with preparation of phosphoric acid
If the preparation of phosphoric acid involves a solvent-solvent extraction
Selective elimination of impurities { (C01B 25/2343 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Concentration concomitant with selective elimination of impurities
Phosphates ( perphosphates C01B 15/16)
References relevant to classification in this group
This subclass/group does not cover:
Perphosphates
{Preparation from liquid orthophosphoric acid or from an acid solution or suspension of orthophosphates ( using ion-exchangers C01B 25/30) }
References relevant to classification in this group
This subclass/group does not cover:
Preparation of alkali metal phosphates using ion-exchangers
Phosphates of magnesium, calcium, strontium, or barium
References relevant to classification in this group
This subclass/group does not cover:
Carbonate-containing phosphates, e,g, carbonated apatite
Fluorine-containing phosphates, e.g. fluoroapatite
{Methods for converting an alkaline earth metal ortho-phosphate into another ortho-phosphate ( by reaction, e.g. of phosphate rock with phosphoric acid C01B 25/322) }
References relevant to classification in this group
This subclass/group does not cover:
Methods by reaction, e.g. phosphate rock, with phosphoric acid
{Preparation by double decomposition}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Double decomposition
Method which consists of adding a Me cation salt solution (Me: Mg, Sr or Ca) to a solution of PO4 anion salt
{After-treatment ( increasing the phosphate content of ores C01B 25/32) }
References relevant to classification in this group
This subclass/group does not cover:
Increasing the phosphate content of ores
Phosphates of heavy metals
Definition statement
This subclass/group covers:

Also classified here are rare earth phosphates

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Heavy metals
Phosphates of metals other than light metals, i.e. alkali metals, alkaline earth metals, Be, Al and Mg.
{having molecular-sieve properties}
Special rules of classification within this group

This group is no longer used for the classification of new documents. New documents should be classified to the appropriate subgroups of C01B 37/00 and C01B 39/00

containing halogen { ( completely halogenated alkali metal phosphates C01D , e.g. lithium hexafluorophosphate C01D 15/005) }
References relevant to classification in this group
This subclass/group does not cover:
Completely halogenated alkali metal phosphates
E.g. lithium hexafluorophosphate
Preparation involving solvent-solvent extraction ( solvent extraction in general B01D 11/00)
References relevant to classification in this group
This subclass/group does not cover:
Solvent extraction in general
{the phosphoric acid present in the medium obtained after reaction being first extracted from the liquid phase formed or separated then re-extracted as free acid by using water or as a phosphate by using a basic compound ( selective extraction of impurities contained in acid C01B 25/237) }
References relevant to classification in this group
This subclass/group does not cover:
Selective extraction of impurities contained in acid
Special rules of classification within this group
  • The extracting agent may be diluted with a compound or a mixture of compounds which are not solvents for phosphoric acid, e.g. a hydrocarbon.
  • Documents which belong to more than one subgroup of C01B 25/462 to C01B 25/466 are classified in combination, C-set used, e.g. C01B 25/462,C01B 25/463,C01B 25/465.
{the extraction being performed on the reaction slurry itself, i.e. without separating the acid (C01B 25/232 takes precedence ) }
Special rules of classification within this group

C01B 25/232 takes precedence

Carbon; Compounds thereof ( {C01B 6/00} , C01B 21/00 , C01B 23/00 take precedence; percarbonates C01B 15/10 ; carbon black C09C 1/48 ; gas carbon production C10B)
Definition statement
This subclass/group covers:

Carbon and compounds thereof. Included in this group are processes and apparatus used in obtaining these products. Also included in this group are processes and apparatus for after-treatments in general, as far as these after-treatments are not limited to a specific type of carbon compound

Preparation of carbonyl fluoride or carbonyl bromide.

References relevant to classification in this group
This subclass/group does not cover:
Compounds of carbon and hydrides of metals
Compounds of carbon and nitrogen
Compounds of carbon and nobles gases
Percarbonates
Carbon black
Gas carbon production
{Carbon fluorides, e.g. (CF) n or (C2F)n ( preparation of intercalation compounds of graphite with fluorine C01B 31/0415) }
Special rules of classification within this group

Preparation of intercalation compounds of graphite are now classified in C01B 31/0415. Group C01B 31/005 is therefore no longer to be used for classification of documents directed to the preparation of intercalation compounds of graphite. The terms "Preparation of intercalation compounds of graphite" cannot be deleted from C01B 31/005 until complete reclassification of relevant documents towards C01B 31/0415.

Preparation of carbon ( by using ultra high pressure, e.g. for the formation of diamonds, B01J 3/06 ; by crystal growth C30B) ; Purification; {After-treatment}
Definition statement
This subclass/group covers:

In particular documents relating carbon products not referred to in C01B 31/0206-C01B 31/14, e.g. carbon gel, carbon aerogel, mesoporous carbon, ordered porous carbon or carbon.

References relevant to classification in this group
This subclass/group does not cover:
Carbon obtained by using ultra high pressure, e.g. for the formation of diamond
Single crystal or homogeneous polycrystalline carbon obtained by crystal growth
{Fullerenes}
Definition statement
This subclass/group covers:

All types fullerenes, their preparation; after-treatments thereof e.g. purification, sorting, functionalization, dispersion in solvents

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Fullerene
Molecule composed entirely of carbon in the form of a hollow sphere
Buckminsterfullerene
Spherical molecule with the formula C60
Endohedral fullerene
Fullerene comprising an element inserted into the fullerene cage
Synonyms and Keywords
Fullerene
Buckyball
{Carbon nanotubes}
References relevant to classification in this group
This subclass/group does not cover:

Specific uses of carbon nanotubes

Informative references
Attention is drawn to the following places, which may be of interest for search:
Coating by vacuum evaporation, by sputtering or by ion implantation of the coating material
Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating
Special rules of classification within this group

All documents in C01B 31/022-C01B 31/0293 are classified with symbols chosen from C01B 2202/00 to C01B 2202/36 to report structural aspects or properties of carbon nanotubes.

Mere references to "carbon nanotubes" in a document in the absence of other details do not lead to a classification in C01B 31/022. For example, a reference to a "carbon nanotube" grown on a substrate used for a semiconductor device is not sufficient for requiring a classification in C01B 31/022. If, however, the document includes specific details on how the nanotube is produced, treated, modified or purified which do not seem trivial, then the classifier should give should classify this document in C01B 31/022-C01B 31/0286. In other terms, documents referring to carbon nanotubes are not automatically classified in C01B 31/00 unless there is emphasis e.g. on the nanotube growing technique or the after-treament.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Carbon nanotubes
Described as graphene sheets rolled up into the shape of a cylinder
Synonyms and Keywords
Nanotubes
Buckytubes
{characterized by the catalyst}
Definition statement
This subclass/group covers:

Included are documents mentioning to different degrees of emphasis the catalyst where nanotubes were grown from (e.g. composition, distribution, particle size, morphology).

{being a continuous process}
References relevant to classification in this group
This subclass/group does not cover:
Production of carbon nanotubes in batches
{After-treatments}
Definition statement
This subclass/group covers:

After-treatments not addressed in C01B 31/0253-C01B 31/0286, e.g. coating of carbon nanotubes.

References relevant to classification in this group
This subclass/group does not cover:
Coatings of a carbon nanotube layer or film with e.g. metallic layer or oxide layer (layered product)
{Sorting}
Definition statement
This subclass/group covers:

All methods for sorting or isolating as-grown mixtures of carbon nanotubes according to e.g. their (n, m) structural form, diameter, bandgap or electronic type (metallic versus semiconducting).

{Opening or filling}
Special rules of classification within this group

A document mentioning the storage of a gas using the physisorption and chemisorption properties of carbon nanotubes should be classified in the class concerned, for example a document addressing the storage of hydrogen should be classified in C01B 3/00. This document should also be circulated to the sorbent field (B01J 20/00).

{Other structures, e.g. nano-onions, nano-scrolls, nano-horns, nano-cones or nano-walls}
Definition statement
This subclass/group covers:

All nanosized carbon materials different from fullerenes and nanotubes, which are characterized by a specific structural aspect.

{Intercalation}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Group C01B 31/0415 is not complete pending a reclassification. See also
{Graphitic oxides, graphitic acids or salts thereof}
Definition statement
This subclass/group covers:

Graphene oxide.

{Graphene}
Definition statement
This subclass/group covers:

The production of graphene aerogel.

References relevant to classification in this group
This subclass/group does not cover:
Production of graphene oxide and graphene oxide arerogel
C01B 31/043 in combination with symbol C01B 2204/00
Informative references
Attention is drawn to the following places, which may be of interest for search:
Groups C01B 31/0438 to C01B 31/0492 are not complete pending a reclassification. See also
Special rules of classification within this group

All documents in groups C01B 31/0438 to C01B 31/0492 are classified with symbols chosen from C01B 2204/00 to C01B 2204/32 to report structural aspects or properties of graphene.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Graphene
one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice or small stacks thereof
{by CVD}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Coating by vacuum evaporation, by sputtering or by ion implantation of the coating material
Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating
{After-treatments}
Definition statement
This subclass/group covers:

E.g. sorting, derivatisation, dispersion of graphene.

Diamond
References relevant to classification in this group
This subclass/group does not cover:
Formation of diamonds using ultra-high pressure
Single crystal or polycrystalline structure in which the grains are aligned in a preferential direction
Active carbon
Definition statement
This subclass/group covers:

Carbon activated by heating to high temperature in the presence of an activating agent for producing an internal porous particle structure.

{After-treatment, e.g. purification ( granulation C01B 31/14) }
References relevant to classification in this group
This subclass/group does not cover:
Granulation of activated carbon
{with "molecular sieve" properties}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
CMS
Carbon molecular sieve
{Reactivation or regeneration ( by a physical process C01B 31/086) }
References relevant to classification in this group
This subclass/group does not cover:
Reactivation or regeneration by a physical process, e.g. by irradiation, by using electric current passing through a carbonaceous feedstock, by using recyclable inert heating bodies
{Apparatus (C01B 31/086 takes precedence ) }
Special rules of classification within this group

C01B 31/086 takes precedence

{Making shaped products, e.g. fibres, spheres, membranes, foam, or the like ( granulation C01B 31/14) }
References relevant to classification in this group
This subclass/group does not cover:
Granulation of activated carbon
Preparation by using gaseous activating agents { (C01B 31/086 , C01B 31/088 take precedence ) }
Definition statement
This subclass/group covers:

Gaseous activation by means of combined-oxygen containing gases, such as steam and CO2.

Special rules of classification within this group

C01B 31/086 and C01B 31/088 take precedence

Preparation by using non-gaseous activating agents { (C01B 31/086 , C01B 31/088 take precedence ) }
Definition statement
This subclass/group covers:

Activation in the presence of non-gaseous activating agents e.g., ZnCl2, H3PO4 or KOH

Special rules of classification within this group

C01B 31/086 and C01B 31/088 take precedence.

{Preparation by impregnation with a metallic compound}
Definition statement
This subclass/group covers:

Activation in the presence of a metallic compound, e.g. ZnCl2

Granulation ( apparatus B01J 2/00)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Granulation in general
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
The term granulation covers:
The methods of preparation of active carbon using carbonaceous precursors per se and binders, e.g. pitch, and producing the granules.
Carbon monoxide ( metal carbonyls C01G)
Definition statement
This subclass/group covers:
Metal carbonyls
Methods for the preparation of carbonates or bicarbonates in general ( percarbonates C15/10; particular individual carbonates, see the relevant groups in C01B to C01G according to the cation )
References relevant to classification in this group
This subclass/group does not cover:
Percarbonates
Particular individual carbonates, according to the cation
Phosgene
References relevant to classification in this group
This subclass/group does not cover:
Carbonyl difluoride
Carbides ( alloys C22)
References relevant to classification in this group
This subclass/group does not cover:
Alloys
{Oxycarbides, sulfocarbides or mixtures of carbides with other bodies, e.g. graphite; Carbides of other non-metals, e.g. silicocarbides, borocarbides}
Special rules of classification within this group

Mixture of carbides, other than those covered by group C01B 31/308, and belonging to more than one of the groups C01B 31/303 to C01B 31/36 are classified in C01B 31/301.

Silicon; Compounds thereof ( {C01B 6/00} , C01B 21/00 , C01B 23/00 take precedence; persilicates C01B 15/14 ; carbides C01B 31/36)
References relevant to classification in this group
This subclass/group does not cover:
Persilicates
Carbides
Informative references
Attention is drawn to the following places, which may be of interest for search:
Apparatus for producing silicon or a compound thereof according to C01B 33/00 to C01B 33/46
Special rules of classification within this group

C01B 6/00, C01B 21/00 and C01B 31/36 take precedence

Silicon ( forming single crystals or homogeneous polycrystalline material with defined structure C30B)
References relevant to classification in this group
This subclass/group does not cover:
Single crystals or homogeneous polycrystalline material with a defined structure
Preparation ( chemical coating from the vapour phase C23C 16/00)
Definition statement
This subclass/group covers:
  • Silicon nanotubes
  • Silicon nanowires without any emphasis on the crystalline structure
References relevant to classification in this group
This subclass/group does not cover:
Chemical coating by decomposition of gaseous precursor
Silicon nanowires (often grown by the methods for the growth of single crystal whiskers) where there is emphasis on the crystalline nature
Purification ( by zone-melting C30B 13/00)
References relevant to classification in this group
This subclass/group does not cover:
Purification by zone melting
Hydrides of silicon
Definition statement
This subclass/group covers:

Hydrides of silicon in the strict meaning of the term.

Metal silicides ( alloys C22)
References relevant to classification in this group
This subclass/group does not cover:
Alloys
Silicon oxides; Hydrates thereof { ( preparing monoxide by reduction of siliceous material C01B 33/182) }
References relevant to classification in this group
This subclass/group does not cover:
Preparation of silicon monoxide by reduction of siliceous material
Silica; Hydrates thereof, e.g. lepidoic silicic acid
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Lepidoid acid
Acid which has a two-dimensional structure. The term "lepidoid" is a generic word for a compound wherein planar bonding predominates and two-dimensional network structures are formed. This lepidoid silicic acid is a special type of polymer silicic acid, wherein its crystalline structure is built up of siloxane bondings.
After-treatment of sols ( { preparation of hydrosols or aqueous dispersions from hydroorganosols, organosols or dispersions in an organic medium C01B 33/141} ; preparation of hydroorganosols, organosols or dispersions in an organic medium from hydrosols {or aqueous dispersions} C01B 33/145)
References relevant to classification in this group
This subclass/group does not cover:
Preparation of hydrosols or aqueous dispersions from hydroorganosols, organosols or dispersions in an organic medium
Preparation of hydroorganosols, organosols or dispersions in an organic medium from hydrosols or aqueous dispersions
Concentration; Drying; Dehydration; Stabilisation; Purification { (C01B 33/1465 takes precedence ) }
Special rules of classification within this group

C01B 33/1465 takes precedence.

{Dehydration into aerogels}
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Silica aerogel
What remains after the extraction of the liquid from the framework of the silica gel in a way that preserves the gel framework’s original volume. This is most often achieved by supercritical extraction.
Preparation of silica xerogels
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Xerogel
What remains when the liquid part of a wet gel is extracted by evaporation or similar methods. The shrinkage during extraction is often important.
Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof ( preparation of aerogels by dehydrating gels C01B 33/158 ; treatment to enhance the pigmenting or filling properties C09C)
References relevant to classification in this group
This subclass/group does not cover:
Preparation of a silica aerogel by dehydrating a wet gel
Treatments of finely divided silica to enhance the pigmenting or filling properties
Silicates ( persilicates C01B 15/14 ; { containing aluminium C01B 33/26} )
References relevant to classification in this group
This subclass/group does not cover:
Persilicates
Silicates containing aluminium
Base exchange silicates, e.g. zeolites ( regeneration B01J 49/00)
Special rules of classification within this group

C01B 33/28 to C01B 33/2892: no longer to be used but cannot be deleted until splitting of groups to C01B 39/00 is completed. Use C01B 39/00 for classification

Alkali metal silicates ( {C01B 33/20 B } , C01B 33/26 take precedence] )
Special rules of classification within this group

C01B 33/26 takes precedence.

{After-treatment, e.g. purification or stabilsation of solutions, granulation; Dissolution; Obtaining solid silicate, e.g. from a solution by spray-drying, flashing off water or adding a coagulant}
References relevant to classification in this group
This subclass/group does not cover:
Obtaining a silicate, e.g. as a hydrate of a crystalline silicate from a solution or a hydrate melt by heating or cooling with or without seeding (not considered as an after-treatment)
having base-exchange properties but not having molecular sieve properties ( regeneration thereof B01J 49/00)
References relevant to classification in this group
This subclass/group does not cover:
Compounds having base-exchange properties and having molecular sieve properties
Layered base-exchange silicates, e.g. clays, micas or alkali metal silicates of kenyaite or magadiite type { ( activation of naturally occurring clays B01J 20/12 ; pillared layered base-exchange silicates B01J 29/049) }
References relevant to classification in this group
This subclass/group does not cover:
Hydrotalcite (layered anion-exchange compound of formula Mg6Al2(CO3)(OH)16•4(H2O)
Activation of naturally occurring clays
Pillared layered base-exchange silicates
Clays
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Clays
phyllosilicate minerals that contain large percentages of water trapped between their silica sheets
Micas; {Interstratified clay-mica products ( delaminated mica or vermiculite platelets obtained by a process involving cation-exchange C04B 14/208) }
References relevant to classification in this group
This subclass/group does not cover:
Delaminated mica or vermiculite platelets obtained by a process involving cation-exchange
Special rules of classification within this group

Also classified here are documents interstratified clay-mica products.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Mica
phyllosilicate mineral having a layered or platy structure, composed of sheets of silicate tetrahedrons. two tetrahedral layers sandwich small metal ions such as aluminum in an octahedral layer
Amorphous silicates, e.g. so-called "amorphous zeolites" ( crystalline zeolites C01B 39/00)
Relationship between large subject matter areas

Catalysts comprising molecular sieves are classified in the group B01J 29/00. B01J 32/00 concerning catalyst carriers is not used but is covered by appropriate groups of B01J 21/00 to B01J 29/00

Solid sorbent composition comprising synthetic zeolitic molecular sieves are classified in B01J 20/00

References relevant to classification in this group
This subclass/group does not cover:
Crystalline silicates having molecular sieve properties
Compounds having molecular sieve properties but not having base-exchange properties
Relationship between large subject matter areas

Compounds classified in main group C01B 37/00 are also classified in other groups of class C01 according to their composition.

Metal organic framework materials (MOFs) is classified in C01B 39/00 or C01B 37/00 depending on their base-exchange properties

MOFs are also classified in C07F.

{Silicates, i.e. so-called metallosilicalites or metallozeosilites}
Definition statement
This subclass/group covers:

Silicates, metallosilicalites, metallozeosilites

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
TS-1 or titanosilicalite-1
MFI-type compound in which some of the silicon atoms are substituted with titanium atoms
TS-2 or titanosilicalite-2
MEL-type compound in which some of the silicon atoms are substituted with titanium atoms
Crystalline silica-polymorphs, e.g. silicalites {dealuminated aluminosilicate zeolites}
Informative references
Attention is drawn to the following places, which may be of interest for search:
Dealuminated aluminosilicate
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Silicalite or silicalite-1
MFI-type polymorph of silica
Silicalite-2
MEL-type polymorph of silica
Aluminophosphates containing other elements, e.g. metals, boron
Definition statement
This subclass/group covers:

aluminophosphates including other elements incorporated into the framework

Compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites; Their preparation; After-treatment, e.g. ion-exchange or dealumination ( treatment to modify the sorption properties, e.g. shaping using a binder, B01J 20/10 ; treatment to modify the catalytic properties, e.g. combination of treatments to make the zeolites appropriate to their use as a catalyst, B01J 29/04 ; treatment to improve the ion-exchange properties B01J 39/14 ; regeneration or reactivation of ion-exchange properties B01J 49/00 ; preparation of stabilised suspensions used in detergents C11D 3/12)
Special rules of classification within this group

Compounds classified in main group C01B 39/00 are also classified in other groups of class C01 according to their composition

Metal organic framework materials (MOFs) are classified in C01B 39/00 or C01B 37/00 depending on their base-exchange properties

MOFs are also classified in C07F.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Zeolites
(i) Crystalline aluminosilicates with base-exchange properties, having three dimensional prous lattice framework of tetrahedral oxide units(ii) Compounds isomorphous to those of the former category, wherein the aluminium or silicon atoms in the framework are partly or wholly replaced by atoms of other elements, e.g. Ga, Ge, P or B.
Crystalline aluminosilicate zeolites; Isomorphous compound thereof; Direct preparation thereof; Preparation thereof starting from a reaction mixture containing a crystalline zeolite of another type, or from preformed reactants; After-treatment thereof
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Organic additive, organic template directing agent, templating agent, template, structure directing agent (SDA), structuring agent
Any component present in the reaction mixture, which directs the formation of the framework about it.
{After-treatment}
Definition statement
This subclass/group covers:

Dealumination of an aluminosilicate zeolite and ion-exchange. Also classified there are documents in which there is a particular emphasis on a process for removing an organic structure directing agent occluded within the as-synthesized zeolite framework. If the removing of the organic structure directing agent is not the invention, only mentioned in the document, it's not classified.

The normal steps of zeolite preparation like synthesis mixture, washing, calcination are not considered as post treatment.

References relevant to classification in this group
This subclass/group does not cover:
Treatment to modify the sorption properties, e.g. shaping using a binder
Treatment to modify the catalytic properties, e.g. combination of treatments to make the zeolites appropriate to their use as a catalyst
Treatment to improve the ion-exchange properties
Regeneration or reactivation of ion-exchange properties
Preparation of stabilised suspensions used in detergents
Preparation of isomorphous zeolites characterised by measures to replace the aluminium or silicon atoms in the lattice framework by atoms of other elements, {i.e. by direct or secondary synthesis}
Definition statement
This subclass/group covers:

Preparation isomorphous zeolites (i.e. wherein the aluminium or silicon atoms in the framework are partly or wholly replaced by atoms of other elements, e.g. Ga, Ge, P or B) obtained by direct or secondary synthesis.

Type A
Definition statement
This subclass/group covers:

Zeolite of LTA structure

References relevant to classification in this group
This subclass/group does not cover:
Preparation using at least one organic template
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Framework topology code LTA
type A, Linde A or Linde type A as exemplified in patent document US2882243
from aqueous solutions of an alkali metal aluminate and an alkali metal silicate excluding any other source of alumina or silica but seeds { (C01B 39/145 takes precedence ) }
Special rules of classification within this group

C01B 39/145 takes precedence

from a reaction mixture containing at least one aluminium silicate or aluminosilicate of a clay type, e.g. kaolin or metakaolin or its exotherm modification or allophane { (C01B 39/145 takes precedence ) }
Special rules of classification within this group

C01B 39/145 takes precedence

Faujasite type, e.g. type X or Y
References relevant to classification in this group
This subclass/group does not cover:
Preparation using at least one organic template
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Framework topology code FAU
Faujasite
Type X (framework topology code FAU)
Linde X or Linde type X exemplified by patent document US2882244
Type Y (framework topology code FAU)
Linde Y or Linde type Y exemplified by patent document US3130007)
Type X { (C01B 39/205 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Synthesis using a template directing agent
Special rules of classification within this group

C01B 39/205 takes precedence

Type Y { (C01B 39/205 takes precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Synthesis using a template directing agent
Special rules of classification within this group

C01B 39/205 takes precedence

Mordenite type { (C01B 39/023 , C01B 39/026 , C01B 39/06 take precedence ) }
References relevant to classification in this group
This subclass/group does not cover:
Preparation using at least one organic template
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Framework topology code MOR
Mordenite
Phillipsite or harmotome type { (C01B 39/023 , C01B 39/026 , C01B 39/06 take precedence ) }
Definition statement
This subclass/group covers:

documents dealing with harmotome or phillipsite type materials.

Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Framework topology code PHI
Phillipsite
Harmotome
natural zeolite with framework topology code PHI
Erionite or offretite type, e.g. zeolite T
References relevant to classification in this group
This subclass/group does not cover:
Preparation using at least one organic template
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Zeolite T (Framework topology code: ERI/OFF
or Linde T exemplified by patent document US2950952
Framework topology code ERI
Erionite
Framework topology code OFF
Offretite
Type L
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Type L (Framework topology code LTL)
Linde L or Linde type L exemplified in patent document US3216789
Type ZSM-4
Definition statement
This subclass/group covers:

Zeolites with framework topology code MAZ.

Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
ZSM4 (Framework topology code MAZ)
exemplified by patent document GB1117568
Omega (Framework topology code MAZ)
exemplified by patent document GB1178186
Framework topology MAZ
Mazzite
Pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence.

{Type ZSM-8; Type ZSM-11; ZSM 5/11 intermediate}
Definition statement
This subclass/group covers:

only the identified type ZSM-8, ZSM-11, ZSM5/11 intermediate

The mixture of MFI and MEL frameworks, any intergrowth of MFI and MEL frameworks are classified in C01B 39/36

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
ZSM-8 (framework topology code MFI/MEL)
exemplified by patent document US3702886; thought to be an intergrowth of ZSM-5 with ZSM-11
ZSM-11 (framework topology code MEL)
exemplified by patent document US3709979
ZSM-5/11 (framework topology code MFI/MEL)
intergrowth product of the ZSM-5 and ZSM-11; exemplified by patent document US4289607
Framework topology code MFI
ZSM-5
Framework topology code MEL
ZSM-11
Type ZSM-5
References relevant to classification in this group
This subclass/group does not cover:
Preparation using at least one organic template
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
ZSM-5 (Framework topology code MFI)
exemplified by patent document US3702886
Type ZSM-12
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Framework topology code MTW
ZSM-12 exemplified by patent document US3832449
Ferrierite type, e.g. types ZSM-21, ZSM-35 or ZSM-38
References relevant to classification in this group
This subclass/group does not cover:
Preparation using at least one organic template
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Framework topology code FER
Ferrierite
ZSM-21 (Framework topology code FER)
exemplified by patent document US4046859
ZSM-35 (Framework topology code: FER)
exemplified by patent document US4046859
ZSM-38 (Ferrierite-type)
exemplified by patent document US4016245
Other types characterised by their X-ray diffraction pattern and their defined composition { (C01B 39/023 , C01B 39/026 , C01B 39/06 take precedence ) }
Definition statement
This subclass/group covers:

zeolites with specific X-ray diffraction pattern and defined composition not classifiable in the subgroups C01B 39/14 to C01B 39/445

References relevant to classification in this group
This subclass/group does not cover:
Preparation using at least one organic template
Special rules of classification within this group

Groups C01B 39/023, C01B 39/026 and C01B36/06 take precedence

Zeolites wherein inorganic bases or salts occlude channels in the lattice framework, e.g. sodalite, cancrinite, nosean, hauynite { ( ultramarine C09C 1/32) }
References relevant to classification in this group
This subclass/group does not cover:
Ultramarine (Na8[(AlO2)6(SiO2)6]S2
Sodalites
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Sodalite
idea unit cell content: Na8[(AlO2)6(SiO2)6]Cl2
Phosphates, e.g. APO or SAPO compounds
Relationship between large subject matter areas

Catalysts compositions are classified in the groups B01J 21/00 to B01J 29/00. B01J 32/00 concerning catalyst carriers is not used but is covered by appropriate groups of B01J 21/00 to B01J 29/00

Informative references
Attention is drawn to the following places, which may be of interest for search:
APO or SAPO with non clearly defined base-exchange properties
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Last Modified: 10/11/2013