U.S. PATENT AND TRADEMARK OFFICE
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U.S. Patent Classification System - Classification Definitions
as of June 30, 2000
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Class 203
DISTILLATION: PROCESSES, SEPARATORY
Class Definition:
GENERAL STATEMENT OF CLASS SUBJECT MATTER
This is the residual class for processes for separating a
liquid mixture (distilland) by vaporizing and condensing at
least a portion thereof to isolate in the condensed liquid
(distillate) or in the unvaporized portion (residue) a
comparatively pure compound which was present as such in the
original mixture. The original mixture may be a solid under
normal atmospheric conditions if it liquifies below the
vaporization temperature.
To come within the purview of this class (203) the distilland
must have a boiling point above 0 deg.C. under normal
atmospheric pressure. Because the C4 hydrocarbons have
boiling points above and below 0 deg.C., all C4 hydrocarbons
are arbitrarily classified as having boiling points above 0
deg.C.
Sublimination (see Glossary) is excluded from this class
(203). See References to Other Classes, below.
When claims are presented which recite a specific chemical
compound or mixture to be recovered, the enumerated
classifications set forth in Lines With Other Classes must be
consulted to see if such subject matter is provided for in
other than Class 203.
LINES WITH OTHER CLASSES AND WITHIN THIS CLASS
LINES WITH CHEMICAL COMPOSITION CLASSES
(1) Products whether claimed in terms of their composition or
claimed in terms of the process of making are classified in
the appropriate composition class even if the process merely
recites a separatory distillation operation.
(2) Processes including a chemical reaction and a separatory
distillation operation are classified here only when the
chemical reaction merely facilitates the isolation by the
separatory distillation operation of a preexisting substance
in the distilland. See Class 260, Chemistry of Carbon
Compounds, Class 423, Chemistry of Inorganic Compounds, or
Class 585, Chemistry of Hydrocarbon Compounds for a process
of preparing a compound and isolating it by a separatory
distillation process.
(3) Processes including a separatory distillation step and a
disparate physical separation step, such as extraction, are
classified in this class (203) if the disparate separating
step follows the distillation step and the process is not
otherwise provided for. When the disparate separation step
precedes the distillation step, the process is generally
provided for elsewhere.
See Class 260, Chemistry of Carbon Compounds (including Class
585, Chemistry of Hydrocarbon Compounds) or Class 423,
Chemistry of Inorganic Componds, for a process of extraction
of a compound, either as a sole step or followed by isolating
the compound by a separatory distillation process.
(4) Processes directed solely to a separatory distillation
operation are classified in this class (203) unless otherwise
provided for:
(a) Processes for the distillation of metals, such as mercury
or zinc are classified in Class 75, Specialized Metallurgical
Processes, Compositions for Use Therein, Consolidated Metal
Powder Compositions, and Loose Metal Particulate Mixtures.
(b) Processes for distilling a mineral oil in which the
product isolated is a pure compound are classified in this
class (203). However, when the distillation process produces
as the product a mineral oil, it is classified in Class 208,
Mineral Oils: Processes and Products.
(c) Processes which include fermentation are classified in
435, Chemistry: Molecular Biology and Microbiology, even if
such processes also include distillation.
(d) Processes for distilling fermented beverage to produce a
distilled beverage are classified in Class 426, Food or
Edible Material: Processes, Compositions, and Products, but
processes for distilling a fermented beverage to isolate
alcohol are classified here (203).
(e) When a patent contains a Class 423, Chemistry of
Inorganic Compounds, process claim and a Class 203,
Distillation: Processes, Separatory, process claim, the
patent is classified in Class 423 and cross-referenced to
Class 203.
PROCESSES INCLUDING EVAPORATION
Processes for evaporating without a condensing step are
generally excluded from this class. For specific lines
between the processes of this class and other processes
including an evaporating step, see below.
This class (203) is distinguished from Class 34, Drying and
Gas or Vapor Contact With Solids, in that the material
treated herein (203) is a liquid or a liquefiable solid from
which volatile material is to be separated and condensed or
absorbed. The product recovered must be a relatively pure
substance which existed as such in the original material. The
material of Class 34 is a solid or semi-solid from which it
is desired to remove a liquid, leaving the residue chemically
unchanged.
Class 134, Cleaning and Liquid Contact With Solids, takes
claimed combinations of work handling or supporting means or
steps with means or steps to apply a liquid to the work, as
by spraying or immersion, where said liquid is distilled or
evaporated, whether or not the resulting vapor is (1)
directly contacted with the work or (2) condensed for reuse
to contact the work. When only the liquid distillation
subcombination or the vapor-phase work contact subcombination
has been claimed, see above for the line between Class 203
and Class 34.
Class 62, Refrigeration, includes processes for separating a
mixture of substances having boiling points below 0 deg.C.
(32 deg.F) at atmospheric pressure by the steps of vaporizing
a component and condensing the vapor. When a patent includes
species claims classifiable in Class 62 and Class 203, it is
classified in Class 62 and cross-referenced to Class 203.
Class 95, Gas Separation: Processes, takes processes in which
gas is removed from a liquid wherein the gas is normally
gaseous at a temperature of 0 deg.C and a pressure of 760 mm
Hg (e.g., hydrogen sulfide (H[subscrpt]2[end subscrpt]S),
carbon monoxide (CO), carbon dioxide (CO[subscrpt]2[end
subscrpt]), etc.). The volatile need not be condensed. The
line between Class 95 and Class 203 is that a Class 203
operation requires vaporizing and condensing a material which
is normally a liquid, while Class 95 does not.
Class 159, Concentrating Evaporators, takes processes for
concentrating solids in solution or suspension by
volatilizing the liquid. It is distinguished from this class
(203) by the fact that the volatile material is not
condensed.
Some additional classes which provide for processes that
include an evaporating step or a concentrating step are:
Class 23, Chemistry: Physical Processes; Class 127, Sugar,
Starch, and Carbohydrates; Class 260, Chemistry, Carbon
Compounds; Class 426, Food or Edible Material: Processes,
Compositions, and Products; Class 520, Synthetic Resins or
Natural Rubbers; Class 585, Chemistry of Hydrocarbon
Compounds; Class 588, Hazardous or Toxic Waste Destruction or
Containment.
CLASS 201, DISTILLATION: PROCESSES, THERMOLYTIC, IS SUPERIOR
TO CLASS 203.
REFERENCES TO OTHER CLASSES
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, subclass 294 For general
sublimation processes see and Class
62, Refrigeration, appropriate subclasses for processes and
apparatus peculiar to removing heat from a substance.
75, Specialized Metallurgical Processes, Compositions for Use
Therein, Consolidated Metal Powder Compositions, and Loose
Metal Particulate Mixtures, appropriate subclasses for a
process of reducing an ore to the metallic state or refining
molten metal involving distillation or for a sublimination
process.
75, Specialized Metallurgical Processes, Compositions for Use
Therein, Consolidated Metal Powder Compositions, and Loose
Metal Particulate Mixtures, for the sublimation of metals.
95, Gas Separation: Processes, for processes involving steps
resulting in separation of a gas from a fluid mixture
comprising (a) a gas and solid or liquid particles entrained
therein, (b) a liquid and gas entrained therein, or (c) a
plurality of gases.
99, Foods and Beverages: Apparatus, 275 for apparatus for
preparing beverages.
106, Compositions: Coating and Plastic, appropriate
subclasses for a coating composition which may be applied to
surfaces of the distillation apparatus or utilized for making
apparatus of a particular composition.
122, Liquid Heaters and Vaporizers, appropriate subclass for
heating liquids, superheating or cooling the vapors generated
and conserving the heat in the liquid or vapor in a closed
system.
134, Cleaning and Liquid Contact With Solids, 1 for a
cleaning process, particularly subclass 12 for a process
including the step of distilling the treating agent and
subclass 31 for a process including the step of condensing a
gas or vapor.
159, Concentrating Evaporators, for apparatus and processes
not more specifically provided for elsewhere, peculiar to the
concentration of solids held in solution or suspension by
evaporation of the liquid containing them. See 48.1 for a
process of concentrating by spraying and subclass 49 for a
process of concentrating by a filming operation. See also
subclasses 5+ for a film type evaporator.
210, Liquid Purification or Separation, appropriate
subclasses for a process for purifying or separating a liquid
by (1) sorption or ionic exchange, (2) filtration, (3)
liquid-liquid extraction, (4) purification by destruction or
conversion of a constituent thereof.
260, Chemistry of Carbon Compounds, subclass 706, for general
sublimation processes.
261, Gas and Liquid Contact Apparatus, appropriate subclasses
for apparatus adapted to produce an intimate contact between
gases and liquids and see (2) Note under the class
definition.
366, Agitating, 219 for apparatus for agitating a liquid or
a particulate material by motion of the container, and
subclasses 241+ for a fixed container with movable stirring
apparatus, particularly subclasses 262+ for pump type
stirrers.
426, Food or Edible Material: Processes, Compositions, and
Products, 11 for processes of preparing alcoholic beverages
including distillation.
585, Chemistry of Hydrocarbon Compounds, subclass 801 for
general sublimation processes.
588, Hazardous or Toxic Waste Destruction or Containment,
appropriate subclasses for distillation process in the
destruction of hazardous or toxic waste.
GLOSSARY:
AZEOTROPIC DISTILLATION
A separatory distillation of a liquid in which a substance is
added to the distilland mixture in order to assist separation
of its components by forming with one or more of the
components a mixture having a minimum boiling point. (The art
has also used the term for a distillation process in which
two substances in the starting material are removed by their
forming a minimum boiling mixture).
CONDENSATE
See "distillate" in the class definition.
CONVECTIVE DISTILLATION
A separatory distillation operation in which an inert vapor
is passed through a heated liquid to reduce the partial vapor
pressure of the component in the liquid desired to be
recovered. It permits the separation of heat sensitive high
boiling substances at temperatures below their decomposition
temperature. Steam distillation is the most commonly used
type of convective distillation.
DISTILLAND
For purposes of this class the liquid or liquefied material
which is undergoing a distillation operation.
DISTILLATE
The liquid product condensed from vapor during the
distillation operation.
EVAPORATION
The process of changing a solid or liquid into a vapor. This
is the generic term for both sublumination and vaporization.
It differs from "distillation" in that distillation includes
the additional step of condensing vapor produced to a
liquid.
EXTRACTIVE DISTILLATION
A separatory distillation in which a generally less volatile
substance, often referred to as a solvent, is added to the
distillation column to preferentially remove some component
of the vapor by dissolving it. The added substance and the
dissolved component are removed below the point at which the
less volatile substance is added to the distillation column.
FLASH VAPORIZATION
The process in which the distilland is heated under pressure
high enough to prevent ebullition (usually above atmospheric
pressure) and the heated distilland is then introduced into a
zone of lesser pressure resulting in the volatilization of at
least a position of the distilland.
FRACTIONAL DISTILLATION
A separatory distillation operation in which distillate is
collected over specific temperature intervals.
MOLECULAR DISTILLATION
A high vacuum separatory distillation process for distilling
high boiling, heat sensitive substances in which the distance
from the liquid surface to the condensing surface is less
than the mean free path.
SEPARATORY DISTILLATION
A process of vaporizing at least a portion of a liquid
mixture (distilland) and condensing at least a portion of the
vapor to separate the liquid mixture into distinct parts. The
substances recovered as products must have preexisted in the
original mixture.
STEAM DISTILLATION
A form of convective distillation in which the inert vapor
passed through the heated liquid is steam. The adding of
water or steam to a distillation column or the adding of
water to a distilland is not within the meaning of this
term.
SUBLIMATION
A process in which a solid passes into the vapor state
without liquefaction and the vapor returns to the solid state
without passing through the liquid phase.
THERMOLYTIC DISTILLATION
A distillation in which material found in the distilland
undergoes chemical decomposition (thermolysis) to form
different substances at least some of which are volatile at
the temperature employed. The volatile substances are
recovered by condensation or sorption.
VAPORIZATION
The process of changing a liquid into a vapor. See
"Evaporation".
SUBCLASSES
Subclass:
1
This subclass is indented under the class definition.
Processes combined with the positive step of visually,
chemically or physically determining some chemical or
physical characteristic or property of the feed, vapor,
residue or condensate.
(1) Note. The chemical or physical characteristic must be
positively stated in the claim for the purpose of this and
indented subclasses, e.g., measuring the temperature. Heating
to a specified temperature is not determining a
characteristic within the purview of this and indented
subclasses.
SEE OR SEARCH CLASS:
73, Measuring and Testing, appropriate subclasses for
measuring and testing apparatus.
137, Fluid Handling, 2 for a process in which a condition or
characteristic of a fluent material is determined and used to
control the system.
162, Paper Making and Fiber Liberation, subclass 238 for a
digester with automatic control means.
196, Mineral Oils: Apparatus, subclass 132 for mineral oil
vaporizing apparatus provided with automatic control.
201, Distillation: Processes, Thermolytic, subclass 1 for a
process directed to thermolytic distillation combined with
measuring, testing or inspecting.
202, Distillation: Apparatus, subclass 151, 160, 193, 196,
206 for distillation apparatus having control devices and see
"SEARCH CLASS" under each subclass.
361, Electricity: Electrical Systems and Devices, appropriate
subclasses for electrical systems not otherwise classified
and see "SEARCH CLASS" under the class definitions for
various types of electrical systems.
436, Chemistry: Analytical and Immunological Testing, 230
for a process of chemically testing not combined with a
distillation process.
Subclass:
2
This subclass is indented under subclass 1. Processes
directed to specifically determining the temperature and/or
pressure of the feed, vapor, residue or condensate.
SEE OR SEARCH CLASS:
73, Measuring and Testing, appropriate subclasses for device
for quantitatively measuring temperature and 700+ for a
device for the direct measurement of pressure.
137, Fluid Handling, 2 for a process of fluid handling in
which one or more characteristics or conditions of a fluent
material are determined, particularly subclass 14 for a
process involving pressure control.
202, Distillation: Apparatus, subclass 160 for a separatory
distillation system including a column provided with
automatic temperature and/or pressure control, and see
"SEARCH THIS CLASS, SUBCLASS" and "SEARCH CLASS" thereunder
for related fields of search.
260, Chemistry of Carbon Compounds, subclass 700 for a
process directed to temperature control.
374, Thermal Measuring and Testing, 100 for a device for
quantitatively determining temperature.
585, Chemistry of Hydrocarbon Compounds, subclass 956 for a
collection of patents concerned with condition-responsive
control procedures in hydrocarbon purification processes.
Subclass:
3
This subclass is indented under subclass 1. Processes
including the steps of determining the concentration of the
feed, vapor, residue or condensate.
SEE OR SEARCH CLASS:
73, Measuring and Testing, 32 for apparatus for determining
density and/or specific gravity of a liquid.
137, Fluid Handling, 2 for a process of fluid handling in
which one or more characteristics or conditions of a fluent
material are determined.
356, Optics: Measuring and Testing, 345 for interferometers
and subclasses 128+ for refractometers.
Subclass:
4
This subclass is indented under the class definition.
Processes combined with a step of removing a contaminant from
the separatory apparatus.
(1) Note. Usually a material, such as a gas, is passed
through the apparatus to remove the contaminant.
SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 241 for degasification of
liquid.
134, Cleaning and Liquid Contact With Solids, 1 for a
process of separating or removing adherent undesired matter
from solid material and subclasses 43+ for apparatus for
cleaning by liquid contact.
137, Fluid Handling, subclasses 15.01-15.26 for a process
of cleaning, repairing or assembling.
201, Distillation: Processes, Thermolytic, subclass 2 for a
process of cleaning the apparatus or removing adhering char
product.
Subclass:
5
This subclass is indented under the class definition.
Processes directed to separating (1) the atoms of a given
element or a compound containing said atoms according to the
atomic weights of said atoms according to the atomic weights
of said atoms or (2) a mixture containing at least two
tautomeric forms of a substance initially in a state of
equilibrium.
(1) Note. A mixture of H2O and D2O is an example of a feed
mixture containing hydrogen atoms of different atomic
weights.
(2) Note. Separating by distillation the ketoenol forms of a
compound is within the purview of this subclass.
SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 31 for processes in which a
plurality of gases is separated by making use of physical
difference in weight.
423, Chemistry of Inorganic Compounds, subclass 580.1 for
processes of producing water and subclass 580.2 for processes
of producing heavy water including a chemical reaction.
Subclass:
6
This subclass is indented under the class definition.
Processes including adding an element or a chemical compound
or mixture (of substances) to the distilland or the vapor to
inhibit or prevent formation of scale on the apparatus and/or
to inhibit or prevent corrosion of the apparatus and/or to
inhibit or prevent an unwanted reaction of the feed, vapor,
residue or condensate.
(1) Note. The addition of a scale inhibiting material to
water being distilled or the addition of a corrosion
inhibiting material to an acidic material being distilled or
the addition of a material which inhibits the polymerization
of an olefin at the temperature of the distillation are
nonlimiting examples of the scope of this and indented
subclasses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
86 for a separatory distillation process including the use
of a surface of a specific composition which thereby inhibits
or prevents an unwanted reaction.
SEE OR SEARCH CLASS:
252, Compositions, 397 for compositions for preventing,
inhibiting or reducing oxidation, chemical decomposition, or
other chemical change.
260, Chemistry of Carbon Compounds, and its daughter Classes
530-570 for a nonhydrocarbon organic compound containing a
stabilizer.
422, Chemical Apparatus and Process Disinfecting,
Deodorizing, Preserving, or Sterilizing, 7 for process of
maintaining an environment nondestructive to metal.
585, Chemistry of Hydrocarbon Compounds, 1 for a hydrocarbon
compound containing a stabilizer.
Subclass:
7
This subclass is indented under subclass 6. Processes
directed to adding a substance to inhibit or prevent
corrosion of the apparatus and/or to inhibit or prevent scale
formation.
SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 133 for a mineral oil
vaporizer having some special feature of construction.
202, Distillation: Apparatus, subclass 267 for apparatus in
terms of the materials of construction.
208, Mineral Oils: Processes and Products, subclass 47 for a
process of treating mineral oil including a step to prevent
or reduce corrosion or erosion of the apparatus employed in
the process and see "SEARCH THIS CLASS, SUBCLASS" and "SEARCH
CLASS" thereunder for related fields of search.
252, Compositions, 175 for water-softening or purifying or
scale-inhibiting agents, and subclasses 387+ for
anti-corrosion agents.
Subclass:
8
This subclass is indented under subclass 6. Processes
directed to adding a substance to inhibit or prevent unwanted
polymerization.
SEE OR SEARCH THIS CLASS, SUBCLASS:
30 for a separatory distillation process in which a
substance is added to cause a desired polymerization of at
least one component.
Subclass:
9
This subclass is indented under subclass 8. Processes
directed to inhibiting or preventing the polymerization of an
unsaturated hydrocarbon.
Subclass:
10
This subclass is indented under the class definition.
Processes of purifying water in which the only material
recovered as a product is water.
SEE OR SEARCH CLASS:
159, Concentrating Evaporators, 5 for concentrating
apparatus of the film type, subclasses 13+ for evaporating
apparatus designed to maintain the liquid being evaporated in
a film and subclass 49 for an evaporating process in which
the liquid to be concentrated is spread in a thin film.
165, Heat Exchange, subclass 3 for a process of adding water
vapor to air or removing water vapor from air.
202, Distillation: Apparatus, subclass 167 for a separatory
distillation apparatus which includes a still and a feed
water heater.
210, Liquid Purification or Separation, 600 for a process of
purifying a liquid not otherwise provided for.
423, Chemistry of Inorganic Compounds, subclass 580.1 for
processes of producing water and 580.2 for processes of
producing heavy water including a chemical reaction.
Subclass:
11
This subclass is indented under subclass 10. Processes in
which distillation is carried out under a pressure greater
than atmospheric or under a vacuum.
SEE OR SEARCH THIS CLASS, SUBCLASS:
73 for a plural distillation process in which at least one
distillation is under pressure or vacuum and subclasses 91+
for a single distillation process carried out under pressure
or vacuum.
Subclass:
12
This subclass is indented under the class definition.
Processes in which only water is removed from the feed
mixture.
(1) Note. For purposes of this and indented subclasses water
is the impurity of the distilland which is to be removed. A
process of removing other impurities as well as water is
excluded.
(2) Note. A plural distillation process of separating only
water by adding an extraneous liquid to the distilland to
alter the relative volatility of water and the liquid be
dried in the initial distillation step and then distilling a
product of the initial distilling operation to separate the
extraneous liquid is classified here.
SEE OR SEARCH THIS CLASS, SUBCLASS:
10 for a process in which the only material recovered as a
product is water and 50+ for a process directed to adding a
specific extraneous material to alter the relative volatility
of a component of a mixture.
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, subclass 306 for a
process of concentrating a solution of a liquid in a liquid
not otherwise provided for.
34, Drying and Gas or Vapor Contact With Solids, appropriate
subclasses, under "Processes" for a process for separating a
liquid from a solid.
62, Refrigeration, 93 for a process of removing moisture
from air.
95, Gas Separation: Processes, appropriate subclasses for
processes of removing water from a gaseous fluid mixture. See
particularly 117 for solid sorption processes to remove
water from a gaseous fluid mixture and subclass 231 for
processes of liquid contacting to remove water from a gaseous
fluid mixture.
Subclass:
13
This subclass is indented under subclass 12. Processes in
which the liquid substance is aqueous nitric acid.
SEE OR SEARCH CLASS:
423, Chemistry of Inorganic Compounds, 390.1 for producing
nitric acid by a chemical reaction.
Subclass:
14
This subclass is indented under subclass 12. Processes for
separating water from an organic compound.
(1) Note. Mixtures of organic substances from which only
water is separated by a distillation step are included in
this and indented subclasses unless otherwise provided for.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, 187 for a process
for removing water from mineral oils and see "Note", "SEARCH
THIS CLASS, SUBCLASS" and "SEARCH CLASS" in subclass 187 for
related processes for removing water from organic mixtures.
260, Chemistry of Carbon Compounds, appropriate subclasses
for a process including removing water by distillation
combined with a step for forming a compound or extracting the
compound from a natural source.
Subclass:
15
This subclass is indented under subclass 14. Processes in
which the organic substance is an organic acid.
(1) Note. The term "organic acid" includes organic compounds
which contain an acid function, e.g., boro, phosphor, sulfa
or carboxylic group and see Class 260, Chemistry of Carbon
Compounds, subclass 500 "(1) Note".
SEE OR SEARCH THIS CLASS, SUBCLASS:
14 for a separatory distillation process for removing only
water from salts or esters of organic acids.
Subclass:
16
This subclass is indented under subclass 15. Processes in
which the organic acid is acetic acid.
Subclass:
17
This subclass is indented under subclass 14. Processes in
which the organic substance is an aldehyde or a ketone.
(1) Note. The terms "aldehyde" and "ketone" include those
compounds having the structure R1COR2 wherein R1 is
hydrocarbon and R2 is either hydrogen or hydrocarbon. See
Class 568, Organic Compounds, subclasses 303 and 420 and the
notes thereunder.
Subclass:
18
This subclass is indented under subclass 14. Processes in
which the organic substance is an alcohol.
(1) Note. For purposes of this and indented subclasses the
term "alcohol" is limited to a hydroxy group bonded to
carbon.
Subclass:
19
This subclass is indented under subclass 18. Processes in
which the alcohol is ethanol.
Subclass:
20
This subclass is indented under the class definition.
Processes directed to defoaming or inhibiting the formation
of foam.
SEE OR SEARCH CLASS:
95, Gas Separation: Processes, subclass 155 for processes of
gas separation involving liquid contacting and the use of a
defoaming or antifoaming agent; subclass 157 for processes of
gas separation involving liquid contacting and defoaming the
liquid; and subclass 242 for defoaming a liquid, per se.
137, Fluid Handling, 107.1 for apparatus for controlling the
degree of foaming in a gas charged liquid.
201, Distillation: Processes, Thermolytic, subclass 9 for a
process of surface treating the solid particles of the charge
to inhibit, reduce or prevent foaming during distillation.
202, Distillation: Apparatus, subclass 264 for distillation
apparatus intended to break foam or inhibit foaming.
435, Chemistry: Molecular Biology and Microbiology, subclass
266 for a fermentation process including the step of
treating the foam produced.
516, Colloid Systems and Wetting Agents; Subcombinations
Thereof; Processes of Making, Stabilizing, Breaking, or
Inhibiting, 115 for processes of or compositions for or
subcombination compositions for the breaking of or inhibiting
of foam colloid systems, when generically claimed or when
there is no hierarchically superior provision in the USPC for
the specifically claimed art.
Subclass:
21
This subclass is indented under the class definition.
Processes directed to recovering waste heat by indirect heat
exchange with (1) a disparate source or (2) a product of a
distillation step.
(1) Note. Heat generated by an engine which runs a
compressor used in the process is a disparate source of
"waste heat" within the scope of this and indented
subclasses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
100 for a digest of distillation processes directed to
specific type of heating.
SEE OR SEARCH CLASS:
34, Drying and Gas or Vapor Contact With Solids, subclass 427
and 513 for a process including conserving heat by indirect
heat exchange.
62, Refrigeration, subclass 96 for a process in which heat
from a gas being cooled is transferred to a heat absorber by
indirect heat exchange, and subclass 113 for a process of
refrigeration in which one function is in heat exchange
relation with a second function.
165, Heat Exchange, appropriate subclasses for heat exchange
apparatus and note Search Class under Class definition for
related fields of search.
196, Mineral Oils: Apparatus, subclass 134 for apparatus for
vaporizing mineral oils including means for heat recovery
from the vapor or residuum.
202, Distillation: Apparatus, subclass 146 for a horizontal
retort with flues wherein the air and/or gas for combustion
is heated by the waste products of combustion by means of a
single-surface heater and subclass 150 for a similar
apparatus using a double-surface heater.
208, Mineral Oils: Processes and Products, subclass 365 for
a process wherein the mineral oil distilland is heated by
indirect contact with a heated product of the distillation.
237, Heating Systems, appropriate subclass for a heating
system which may use the heat rejecting portion of a
refrigeration system with additional heating means.
261, Gas and Liquid Contact Apparatus, 158 for apparatus for
indirect interchange of heat between contact fluids.
Subclass:
22
This subclass is indented under subclass 21. Processes in
which the feed is heated by the recovered waste heat.
SEE OR SEARCH CLASS:
34, Drying and Gas or Vapor Contact With Solids, subclass 513
for a process of including the step of exchanging heat
between the incoming and outgoing gases.
196, Mineral Oils: Apparatus, subclass 134 for mineral oil
vaporizing apparatus having means for preheating the oil by
the heat of the vapor or residue.
201, Distillation: Processes, Thermolytic, 14 for a
thermolytic distillation process directed to using a
conversion product as an indirect source of heat for heating
the feed.
202, Distillation: Apparatus, subclass 159 for a
distillation system including a device for heating the feed
with a product of the distillation step and subclasses 177+
for a still system including a device for preheating the feed
with a product of the distillation step.
Subclass:
23
This subclass is indented under subclass 22. Processes in
which distillation residue is the source of recovered heat.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, subclass 353 for
a process wherein one component being distilled is heated by
indirect heat exchange of a component of the process, usually
by the residue.
Subclass:
24
This subclass is indented under subclass 22. Processes in
which compressed vapor is the source of waste heat.
Subclass:
25
This subclass is indented under subclass 21. Processes in
which the distillation zone is heated by the recovered waste
heat.
SEE OR SEARCH CLASS:
202, Distillation: Apparatus, subclass 174 for multiple
effect still series apparatus, 187 for apparatus in which the
still and condenser are concentric and 192 for apparatus to
which the cooling liquid in the condenser passes to the still
to be distilled.
Subclass:
26
This subclass is indented under subclass 25. Processes, in
which the source of waste heat is compressed vapor.
Subclass:
27
This subclass is indented under subclass 21. Processes, in
which the recovered waste heat is utilized in a step
subsequent to the step in which the heat was produced.
Subclass:
28
This subclass is indented under the class definition.
Processes including the step of producing a chemical reaction
of a component of the mixture being separated to facilitate
separation of the desired substance in the original mixture.
(1) Note. To come within the purview of this and indented
subclasses a chemical change must occur which facilitates the
recovery without chemical change of the desired substance
which was present in the original mixture.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, 46 for a process
of treating mineral oil which results in a chemical
alteration of at least some of the hydrocarbon molecules
thereof.
546, Organic Compounds, 134 for a general process of
chemically treating a carbon compound not otherwise provided
for.
588, Hazardous or Toxic Waste Destruction or Containment,
appropriate subclasses for the use of a chemical reaction
with distillation as part of a process of the destruction of
hazardous or toxic waste.
Subclass:
29
This subclass is indented under subclass 28. Processes,
directed to adding a catalyst or a material which reacts with
a component of the mixture to assist the separation of the
desired component in the original mixture.
(1) Note. A chemical reaction for purposes of this and
indented subclasses includes such reactions as (1) forming
hydrates, (2) adjusting of hydrogen ion concentration, (3)
polymerizing a component, (4) oxidizing or reducing a
component or the addition to the mixture being acted upon of
an oxidizing or reducing agent, and (5) the forming of
different substances.
SEE OR SEARCH THIS CLASS, SUBCLASS:
50 for adding a substance to alter the relative volatility
of components of the incoming feed without specifically
producing a new chemical compound.
Subclass:
30
This subclass is indented under subclass 29. Processes, in
which the added material causes unwanted material in the feed
to enter a reaction forming polymeric material.
SEE OR SEARCH CLASS:
520, Synthetic Resins or Natural Rubbers, 1 for a process of
polymerizing, per se, and products resulting therefrom.
530, Chemistry: Natural Resins or Derivatives; Peptides or
Proteins; Lignins or Reaction Products Thereof, 211 for a
process polymerizing, per se, and products resulting
therefrom.
554, Organic Compounds, subclasses 25-29 for a process
polymerizing, per se, and products resulting therefrom.
585, Chemistry of Hydrocarbon Compounds, 502 for olefin
polymerization processes; and subclass 832 for a hydrocarbon
purification process which involves polymerization and
depolymerization.
Subclass:
31
This subclass is indented under subclass 29. Processes,
directed to adding an oxidizing substance.
(1) Note. This subclass is limited to incorporating a
substance which is stated to oxidize a part of the material
being treated or is a well-known oxidizing agent.
(2) Note. Nitric acid is classified here and crossed to
subclass 34.
SEE OR SEARCH CLASS:
260, Chemistry of Carbon Compounds, appropriate subclass for
a process of purification by an oxidative treatment of a
particular carbon compound and subclass 702 for a general
process of oxidation of impurities. See (1) Note under
subclass 702.
585, Chemistry of Hydrocarbon Compounds, 833 for a
purification process involving the addition of an oxidizing
agent to a hydrocarbon feedstock.
Subclass:
32
This subclass is indented under subclass 29. Processes
directed to adding a reducing substance.
(1) Note. This subclass is limited to incorporating a
substance which is stated to reduce a part of the material
being treated or is a well known reducing agent, e.g.,
hydrogen.
SEE OR SEARCH CLASS:
260, Chemistry of Carbon Compounds, appropriate subclasses
for a process of purifying by a reductive treatment, a
particular carbon compound and subclass 701 for a general
process of reductive treatment.
585, Chemistry of Hydrocarbon Compounds, 258 and 841 for
hydrogenative purification of hydrocarbons.
Subclass:
33
This subclass is indented under subclass 29. Processes, in
which the reactive material added is a metal or ammonium salt
of an inorganic oxygen containing acid.
(1) Note. This subclass takes acid, neutral and basic salts
of oxygen containing inorganic acids, e.g., NaHSO4, Na2SO4,
CuCO3, Cu(OH)2.
Subclass:
34
This subclass is indented under subclass 29. Processes, in
which the added material is an acid.
(1) Note. For purposes of this and indented subclasses the
term "acid" includes inorganic compounds which contain
hydrogen as the cation and under subclass 15 see (1) Note for
definition of organic acids.
SEE OR SEARCH THIS CLASS, SUBCLASS:
33 for processes in which the reacting material is a complex
inorganic acid salt, e.g., NaHCO3.
Subclass:
35
This subclass is indented under subclass 34. Processes in
which the acid is phosphoric or sulfuric.
Subclass:
36
This subclass is indented under subclass 29. Processes, in
which the added material is an alkaline oxide or an alkaline
hydroxide.
(1) Note. This subclass is limited to the oxides and
hydroxides of alkali metals, alkaline earth metals including
magnesium and the scandium group metals.
Subclass:
37
This subclass is indented under subclass 36. Processes, in
which the material is an alkali metal hydroxide.
Subclass:
38
This subclass is indented under subclass 29. Processes, in
which the added material is organic.
(1) Note. To come within the purview of this subclass an
organic compound must be clearly disclosed to react with a
component of the mixture being treated to form a new
compound.
(2) Note. See class definition of Class 260, Chemistry of
Carbon Compounds, for the scope of the term "organic".
(3) Note. A separatory distillation process of adding an
organic compound, such as an alcohol or an acid, to form in
situ an ester which assists separation is classified here and
cross-referenced to the appropriate indented subclass under
subclass 57.
Subclass:
39
This subclass is indented under the class definition.
Processes combined with subjecting the material being
vaporized, the vapor, the distillate or the residue to a
disparate physical treatment to remove a substance.
(1) Note. A process merely including the step of separating
the immiscible layers of the distillate, e.g., decanting, is
not considered a disparate separation for this and indented
subclasses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
50 for a separatory distillation process including the step
of separating the distillate layers in an azeotropic type
distillation and subclasses 76, 79, 83, 85, 92+, and 95+,
when the azeotroping agent is water only.
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, 293 for a general
physical process not otherwise classified and under subclass
293, see "SEARCH THIS CLASS, SUBCLASS" and "SEARCH CLASS" for
related fields of search.
95, Gas Separation: Processes, for processes of gas
separation, per se.
201, Distillation: Processes, Thermolytic, 3 for a process
of physical separating of a solid in the removed by product
mixture.
208, Mineral Oils: Processes and Products, subclass 369 for
a process of distilling mineral oil involving some
noncondensation treatment of the volatiles evolved during
distillation and subclass 349 for a process in which the
liquid condensate or the residue resulting from the
distillation is subjected to a nonvaporizing treatment.
260, Chemistry of Carbon Compounds, 236.5 for a process for
preparing and treating extracts. See "Notes" under subclass
236.5 and "SEARCH THIS CLASS, SUBCLASS" and under subclass
236.6. Subclasses 704+, includes general physical processes
of treating a carbon compound not otherwise provided for.
585, Chemistry of Hydrocarbon Compounds, 802 for hydrocarbon
purification by plural serial diverse separations.
Subclass:
40
This subclass is indented under subclass 39. Processes,
directed to removing entrained solid or liquid particles from
gas or vapor in the distillation operation.
SEE OR SEARCH CLASS:
95, Gas Separation: Processes, for processes, per se, of
removing solid or liquid particles entrained in a gas.
122, Liquid Heaters and Vaporizers, subclass 492 for a
device in the steam dome of a boiler for separating water
from steam.
137, Fluid Handling, 544 for fluid handling apparatus
including means for separating solid material from a fluid
and see "SEARCH THIS CLASS, SUBCLASS" and "SEARCH CLASS"
under subclass 544 for related fields of search.
202, Distillation: Apparatus, subclass 197 for apparatus in
which vapor deposits entrained solid or liquid particles.
209, Classifying, Separating, and Assorting, subclasses 19-37
and 133+ for a process of using free suspension in a gas or
separating solid components of a mixture.
Subclass:
41
This subclass is indented under subclass 39. Processes,
directed to material being treated being acted upon with a
solid sorbent to assist separation of a desired product.
(1) Note. The sorbent must contact the distilland during
distillation or a product of the distillation step.
SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 90 for processes, per se, of
gas separation utilizing solid sorption.
202, Distillation: Apparatus, subclass 200 for distillation
apparatus in which the vapor is passed through porous
material or other porous material.
208, Mineral Oils: Processes and Products, subclass 310 for
a process wherein a mineral oil containing fluid is contacted
with a solid sorptive material, and note "SEARCH THIS CLASS,
SUBCLASS" and "SEARCH CLASS" thereunder.
210, Liquid Purification or Separation, 660 for a process of
purifying a liquid by sorption.
502, Catalyst, Solid Sorbent, or Support Therefor: Product or
Processes of Making, 60 and 400+ for a sorbent composition.
Subclass:
42
This subclass is indented under subclass 39. Processes,
directed to extracting a component from gas or vapor with a
liquid.
SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 149 for processes, per se, of
gas separation utilizing liquid contacting.
208, Mineral Oils: Processes and Products, subclass 311 for
a process in which mineral oil is mixed with a liquid which
will form with a portion of the oil a liquid phase which is
immiscible with the rest of the oil and note "SEARCH THIS
CLASS, SUBCLASS" and "SEARCH CLASS" thereunder.
260, Chemistry of Carbon Compounds, subclass 708 for a
process including treatment for absorbing impurities, and
note "SEARCH CLASS" thereunder.
261, Gas and Liquid Contact Apparatus, appropriate subclasses
for apparatus for contacting a gas and a liquid.
585, Chemistry of Hydrocarbon Compounds, 833 for hydrocarbon
purification by solvent extraction.
Subclass:
43
This subclass is indented under subclass 39. Processes
directed to extracting a liquid product of a distillation
step with a liquid.
(1) Note. The extraction with a liquid must take place
subsequent to the vaporization of the distilland. The liquid
extracted may be the initial distillate or residue or a
product of a subsequent distillation operation.
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, 306 for process of
concentrating a liquid in liquid.
95, Gas Separation: Processes, subclass 190 for processes,
per se, of gas separation utilizing liquid contacting and
separation of liquid from the contact liquid by liquid-liquid
extraction.
208, Mineral Oils: Processes and Products, 311 for a process
in which mineral oil is mixed with or contacted with another
liquid which will dissolve or is miscible with a portion or
fraction of the oil and by so doing forming a liquid phase
which is immiscible with another portion or fraction,
particularly subclass 339 and under subclass 311 see "SEARCH
THIS CLASS, SUBCLASS" and "SEARCH CLASS" for related fields
of search.
210, Liquid Purification or Separation, 634 for a process of
extracting a solute from a liquid solution by contacting the
solution with a second liquid.
260, Chemistry of Carbon Compounds, and its daughter Classes
530-570 appropriate subclasses for a process of isolating or
purifying a nonhydrocarbon carbon compound including a liquid
extraction step and subclass 705 for a process including
extracting a carbon compound from a mixture.
423, Chemistry of Inorganic Compounds, appropriate subclasses
for a process of isolating or purifying an inorganic compound
by an extracting, leaching or dissolving step.
424, Drug, Bio-Affecting and Body Treating Compositions, for
a process of producing a composition of that class and which
may include an extraction step. See especially 123, 195.1+
and 520+.
426, Food or Edible Material: Processes, Compositions, and
Products, 425 for extracting or using a liquid as an
extracting medium.
585, Chemistry of Hydrocarbon Compounds, 833 for hydrocarbon
purification by solvent extraction.
Subclass:
44
This subclass is indented under subclass 43. Processes in
which the extracted liquid is a distillate.
Subclass:
45
This subclass is indented under subclass 44. Processes,
directed to distilling the distillate after it has been
extracted with a liquid.
(1) Note. The raffinate phase is that part of the distillate
which does not dissolve in the extracting liquid during the
liquid extraction step.
SEE OR SEARCH THIS CLASS, SUBCLASS:
74 and 81+, for a plural separatory distillation process in
which the initial distillate is distilled.
Subclass:
46
This subclass is indented under subclass 44. Processes,
directed to distilling the extracting liquid phase subsequent
to the extraction step.
(1) Note. The extracting liquid phase is the liquid composed
of the extracting liquid and the portion of the distillate
soluble therein.
Subclass:
47
This subclass is indented under subclass 39. Processes,
directed to separating a solid material from a product of the
distillation step.
SEE OR SEARCH CLASS:
210, Liquid Purification or Separation, 600 for a process of
separating a solid from a liquid, especially subclasses 702+
for an accretion or precipitation process; and subclasses
767+ for a skimming, settling, or filtration process.
Subclass:
48
This subclass is indented under subclass 47. Processes
directed to crystallizing a component from a product of the
distillation step.
(1) Note. The fact that the solid material is crystalline
must be stated in the claim.
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, 295 for a process
including crystallization and under subclass 295, see "SEARCH
CLASS" for related crystallization processes.
127, Sugar, Starch, and Carbohydrates, 58 for a process of
crystallizing sugar from a solution.
260, Chemistry of Carbon Compounds, subclass 707 for a
process of physically treating an organic compound which
includes the step of crystallizing.
585, Chemistry of Hydrocarbon Compounds, 812 for a
hydrocarbon separation or purification process which includes
chilling to form a solid.
Subclass:
49
This subclass is indented under the class definition.
Processes directed to passing through the material being
distilled a normally gaseous substance.
(1) Note. A substance to be considered "normally gaseous"
must have a boiling point below - 10oC at atmospheric
pressure. Air, ammonia, carbon dioxide, dimethyl ether and
propane are some examples of "normally gaseous" substances.
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, subclass 307 for a
process of concentrating a solution of a liquid in a liquid
in which the liquid being concentrated is directly contacted
with the concentrating medium (e.g., hot gases).
95, Gas Separation: Processes, 263 for degasification of a
liquid by stripping with a gas.
202, Distillation: Apparatus, subclass 134 for a retort
having provision for injecting a fluid for convective
separation of the distillate.
208, Mineral Oils: Processes and Products, subclass 356 and
362 for a process of distilling mineral oil in the presence
of an added gas or vapor, and subclass 43 for a process of
contacting tar with high temperature gas during
distillation.
261, Gas and Liquid Contact Apparatus, appropriate subclasses
for apparatus adapted to produce an intimate contact between
gases and liquids, particularly 121 for devices for
discharging gases beneath the surface of a liquid.
Subclass:
50
This subclass is indented under the class definition.
Processes including the step of adding material other than
water or steam per se to the distilland or distillation
zone.
(1) Note. This subclass and indented subclasses include
azeotropic and extractive distillations in which additional
material other than water or steam alone is added to alter
the relative volatility of components of the distilland to
assist the distillative separation. Usually the material is
added to the distilland or the distillation zone. Recycling
all or part of a product of the distillation is not
considered adding an additional material for purposes of this
and indented subclasses.
(2) Note. The use of water or steam in addition to the added
material is within the scope of this and indented
subclasses.
(3) Note. When two or more distinct species of added
substance are claimed, the patent is placed in the subclass
first providing for a species. When a species claimed is not
specifically provided for, the patent is placed in the
generic subclass (50 or 57) and cross-references to the
subclasses providing for the other species.
(4) Note. See Class 260, Chemistry of Carbon Compounds,
class definitions, Definition of Terms Employed in this
Class, and appropriate subclasses for definitions of terms
for organic compounds used in this and indented subclasses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
12 for a process for reducing only the water content of the
distilland in which additional material assists the
distillative separation and subclasses 76, 79, 83, 85, 92+,
and 95+ for a separatory distillation process in which only
water or steam is the additional material added.
29 for a separatory distillation process in which the added
material reacts with a component of the material being
separated or catalyzes a chemical reaction.
39 for a distillation process in which an extraneous
material is utilized to assist a disparate physical
separation such as extraction or sorption.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, subclass 356 and
362 for a process of distilling mineral oil in the presence
of an added gas or vapor, and subclass 313 for a process of
distilling mineral oil in the presence of a selective
solvent. Under subclass 362 see "SEARCH THIS CLASS, SUBCLASS"
and "SEARCH CLASS" for related fields of search.
Subclass:
51
This subclass is indented under subclass 50. Processes in
which plural materials are added.
(1) Note. Each of the added materials may be repeatedly
added to the distilland at different points in the same
distillation zone, for the purpose of this subclass.
(2) Note. When a series of distillations is carried out and
a different substance is added in separate distillations, the
process is treated as adding a single substance and
classified under subclass 50 according to the claimed added
substance first appearing.
Subclass:
52
This subclass is indented under subclass 51. Processes in
which a mixture of hydrocarbons is added.
(1) Note. Benzine, gasoline and kerosene are examples of
hydrocarbon mixtures.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, 14 for mineral
oil mixtures.
Subclass:
53
This subclass is indented under subclass 51. Processes in
which the additional material comprises water or stream and
at least one other substance.
(1) Note. For purposes of this and indented subclasses the
plural component mixture added includes a solution, a
suspension, or water and at least one other substance added
separately to produce a complementary result.
Subclass:
54
This subclass is indented under subclass 53. Processes in
which another substance comprises an aldehyde or a ketone.
Subclass:
55
This subclass is indented under subclass 53. Processes in
which the other substance comprises an alcohol.
Subclass:
56
This subclass is indented under subclass 51. Processes in
which the additional material comprises an alcohol or an
ether and at least one other substance.
Subclass:
57
This subclass is indented under subclass 50. Processes in
which the additional material is an organic compound.
(1) Note. See Class 260, Chemistry of Carbon Compounds,
Class Definitions, Definitions of Terms Employed In This
Class, and appropriate subclasses for definitions of terms
used in this and indented subclasses.
SEE OR SEARCH CLASS:
260, Chemistry of Carbon Compounds, appropriate subclass for
a particular nonhydrocarbon organic compound.
585, Chemistry of Hydrocarbon Compounds, 16 for a
hydrocarbon compound per se, and subclasses 864+ for
hydrocarbon purification involving use of an organic agent.
Subclass:
58
This subclass is indented under subclass 57. Processes in
which the organic compound is heterocyclic.
(1) Note. The term heterocyclic denotes the presence of a
ring whose members are composed of at least one carbon atom
and one or more atoms of the elements taken from the group
consisting of nitrogen, oxygen, sulfur, selenium and
tellurium.
(2) Note. Carbohydrates and their derivatives unless shown
to be acyclic are presumed to be heterocyclic compounds.
SEE OR SEARCH THIS CLASS, SUBCLASS:
57 for a distillation process utilizing a ring oregano boron
or oregano phosphorus compound.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, 325 for a process
of fractionating mineral oil in which a heterocyclic organic
compound is a selective solvent.
Subclass:
59
This subclass is indented under subclass 57. Processes in
which the organic compound is an amine.
(1) Compounds containing amino and other functional groups
are classified here and cross-referenced to the other
functional groups appearing below.
Subclass:
60
This subclass is indented under subclass 57. Processes in
which the organic compound is an ester.
(1) Note. For purposes of this subclass the term "ester"
includes amide and nitrite.
SEE OR SEARCH THIS CLASS, SUBCLASS:
38 for a separatory distillation process in which an organic
acid or an alcohol is added to form in situ an ester which
aids separation by changing the relative volatility of
components of the distilland.
Subclass:
61
This subclass is indented under subclass 57. Processes in
which the organic compound is an acid.
SEE OR SEARCH THIS CLASS, SUBCLASS:
15 for the scope of the term "and".
Subclass:
62
This subclass is indented under subclass 57. Processes in
which the organic compound is an aldehyde or a ketone.
SEE OR SEARCH THIS CLASS, SUBCLASS:
17 for the meaning of "aldehyde" and "ketone".
Subclass:
63
This subclass is indented under subclass 57. Processes in
which the compound is an alcohol or an ether.
(1) Note. As used in this and indented subclasses the term
"alcohol" includes the monohydroxy and polyhydroxy organic
compounds such as: butanol, glycol, glycerol, sorbitol,
cyclohexanol, phenol, (ROH).
(2) Note. As used in this and indented subclasses the term
"ether" includes organic compounds in which the hydrogen of
at least one alcohol group has been replaced by a hydrocarbon
radical.
SEE OR SEARCH THIS CLASS, SUBCLASS:
57 for a process using a mercaptan (thiol alcohol) or an
organic sulfide (thiol ether) without other significant
groups.
59 for a process in which the added material is an amino
alcohol.
Subclass:
64
This subclass is indented under subclass 63. Processes in
which the compound is polyhydroxy alcohol or an ether
derivative thereof.
Subclass:
65
This subclass is indented under subclass 63. Processes in
which the organic compound is a hydroxy aromatic, e.g.,
phenol, naphthol, cresol.
Subclass:
66
This subclass is indented under subclass 63. Processes in
which the alcohol is methanol.
Subclass:
67
This subclass is indented under subclass 57. Processes in
which the compound is a halogenated hydrocarbon.
(1) Note. Organic compounds which contain only carbon,
hydrogen and halogen are halogenated hydrocarbons.
SEE OR SEARCH CLASS:
260, Chemistry of Carbon Compounds, 648 for compounds which
contain halogen bonded to carbon.
Subclass:
68
This subclass is indented under subclass 57. Processes in
which the compound is a hydrocarbon.
(1) Note. For purposes of this and indented subclasses the
term "hydrocarbon" is limited to compounds consisting of
carbon and hydrogen.
SEE OR SEARCH THIS CLASS, SUBCLASS:
12 for a process of separating only water in which a
hydrocarbon is the azeotroping agent.
43 for a process in which the extracting liquid is a
hydrocarbon.
52 for a process of adding a mixture of hydrocarbons to
assist separation during distillation.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, subclass 337 for
a process of fraction- ating mineral oil using a hydrocarbon
as a solvent.
585, Chemistry of Hydrocarbon Compounds, appropriate
subclasses for compounds which consist of carbon and hydrogen
only.
Subclass:
69
This subclass is indented under subclass 68. Processes in
which the hydrocarbon is aromatic.
(1) Note. A compound consisting of carbon and hydrogen
characterized by the presence of a benzene nucleus is an
aromatic hydrocarbon.
SEE OR SEARCH CLASS:
585, Chemistry of Hydrocarbon Compounds, subclass 16 and 18
for a hydrocarbon which contains a benzene nucleus.
Subclass:
70
This subclass is indented under subclass 68. Processes in
which the hydrocarbon is acyclic.
(1) Note. A compound consisting of carbon and hydrogen and
having an open chain structure, only, is an acyclic
hydrocarbon.
SEE OR SEARCH CLASS:
585, Chemistry of Hydrocarbon Compounds, subclass 16 and 18
for a hydrocarbon which is acyclic.
Subclass:
71
This subclass is indented under the class definition.
Processes directed to utilizing at least two distilling
operations to separate components present in the original
mixture.
(1) Note. The second distilling operation may be performed
on all or a part of a distillate, a side stream or a residue
from the initial distilling operation.
(2) Note. For purposes of this and indented subclasses an
operation is considered to be a plural operation if (a) a
part of a distilland is removed by distillation and the
residue in the still is further distilled under a different
pressure or with the addition or absence of water or steam
and (b) two or more distillation systems are used regardless
as to whether there is an intermediate condensation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
21 for a plural distillation process in which useful heat is
recovered by indirect heat exchange.
43 for a plural distillation process in which a residue of a
distillation operation is extracted with a liquid.
44 for a plural distillation process in which a distillate
of a distillation operation is extracted with a liquid.
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, subclass 306 for a
process of concentrating a solution of a liquid in a liquid
not otherwise provided for.
159, Concentrating Evaporators, 47.1, for a process of
concentrating a liquid, and see "SEARCH CLASS" thereunder for
related fields of search.
196, Mineral Oils: Apparatus, 105 for a plurality of
interconnected mineral oil vaporizers.
202, Distillation: Apparatus, subclass 154 and 155 for
separatory distillation apparatus having plural columns
and/or plural stills and subclass 173 for a plurality of
stills so connected that either the vapor or the residue of
one flows into the other.
208, Mineral Oils: Processes and Products, 354 and 364+ for
a process of distilling mineral oil wherein the vaporization
is carried out in a plurality of separate and distinct
operations.
Subclass:
72
This subclass is indented under subclass 71. Processes in
which at least one distilling operation is directed to
introducing the distilland into the vaporization zone by
spreading it as a thin film over a surface.
(1) Note. The surface on which the distilland is spread may
be liquid, solid or foraminous.
SEE OR SEARCH THIS CLASS, SUBCLASS:
89 for a process involving a single distillation operation
in which the distilland is spread as a thin film over a
surface.
SEE OR SEARCH CLASS:
159, Concentrating Evaporators, 5 for concentrating
apparatus of the film type including subclasses 13+ for
evaporating apparatus designed to maintain the liquid being
evaporated in a film and subclass 49 for an evaporating
process in which the liquid to be concentrated is spread in a
thin film.
196, Mineral Oils: Apparatus, subclass 128 for vaporizing
apparatus for distilling mineral oil in a thin film.
202, Distillation: Apparatus, subclass 236 for separatory
distillation apparatus in which the still has means for
intro- ducing the distilland into the still in the form of a
spray or the distilland is introduced into the still in the
form of a film.
208, Mineral Oils: Processes and Products, subclass 360 for
a process of distilling mineral oil wherein the oil is spread
as a thin film on a surface.
Subclass:
73
This subclass is indented under subclass 71. Processes in
which at least one distillation operation is carried out
under a pressure greater than atmospheric or under a vacuum.
SEE OR SEARCH THIS CLASS, SUBCLASS:
43 for a distillation separatory process in which the
initial residue is extracted with a liquid.
91 for a single distillation process carried out at a
pressure greater or less than atmospheric pressure and see
"SEARCH CLASS" under subclass 91 for related fields of
search.
SEE OR SEARCH CLASS:
202, Distillation: Apparatus, subclass 205 for a separatory
distillation system provided with means for producing a
vacuum therein.
Subclass:
74
This subclass is indented under subclass 73. Processes, in
which at least a portion of the distillate from the initial
distillation operation is subjected to at least one
subsequent distillation operation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
45 and 46, for a process of separatory distillation
including extracting a distillate with an immiscible liquid.
Subclass:
75
This subclass is indented under subclass 74. Processes in
which a product from a later distillation operation is
returned in terms of the process to a distillation zone prior
to the distillation zone in which the product was produced.
(1) Note. The prior distillation zone must be in the series
of distillation operations which produced the product being
returned.
(2) Note. The product returned may be all or a part of a
product of a second or subsequent distillation operation in a
series.
SEE OR SEARCH CLASS:
165, Heat Exchange, 104.21 for apparatus in which liquid is
vaporized at one zone, condensed at another and the
condensate is returned to the first zone.
196, Mineral Oils: Apparatus, subclass 99 for mineral oil
distilling apparatus including the combination of a
vaporizer, condensing means with means for returning a part
or all of the condensate to the vaporizer.
208, Mineral Oils: Processes and Products, subclass 355 for
a process of subjecting mineral oil to at least two
distillation operations in which either vapors, condensate,
and/or residue from a later distillation zone is returned to
an earlier distillation zone.
Subclass:
76
This subclass is indented under subclass 74. Processes,
directed to adding water or steam to at least one
distillation operation.
(1) Note. Water or steam is usually added to the
distillation operation to change the relative volatility of
the components of the material being distilled.
Subclass:
77
This subclass is indented under subclass 74. Processes in
which the initial distillation is carried out under a
pressure greater than atmospheric or under a vacuum.
Subclass:
78
This subclass is indented under subclass 73. Processes in
which a product from a later distillation operation is
returned in term of the process to a distillation zone prior
to the distillation zone in which the product was produced.
SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 99 for mineral oil
distilling apparatus including the combination of a
vaporizer, condensing means with means for returning a part
or all of the condensate to the vaporizer.
208, Mineral Oils: Processes and Products, subclass 355 for
a process of subjecting mineral oil to at least two
distillation operations in which either vapors, condensate,
and/or residue from a later distillation zone is returned to
an earlier distillation zone.
Subclass:
79
This subclass is indented under subclass 73. Processes
directed to adding water or steam to at least one
distillation operation.
(1) Note. Water or steam is usually added to the
distillation operation to change the relative volatility of
the components of the material being distilled.
SEE OR SEARCH THIS CLASS, SUBCLASS:
95 for a single distillation process in which water is added
and under subclass 95, see "SEARCH CLASS" for related fields
of search.
Subclass:
80
This subclass is indented under subclass 73. Processes in
which the initial distillation is carried out under a
pressure greater than atmospheric or under a vacuum.
SEE OR SEARCH THIS CLASS, SUBCLASS:
77 for a process including the step of distilling the
initial distillate in which the initial distillation is under
a pressure greater or less than atmospheric pressure.
Subclass:
81
This subclass is indented under subclass 71. Processes
directed to distilling all or a part of the distillate from
the initial distillation operation.
(1) Note. The term "distillate" includes the portion of the
incoming feed which is taken off "overhead" or taken off as a
"side stream".
SEE OR SEARCH THIS CLASS, SUBCLASS:
43 for a separatory distillation process in which the
initial residue is extracted with a liquid.
45 and 46, for a plural distillation process including
extracting a distillate with a liquid and distilling the
raffinate phase or the extractant phase.
Subclass:
82
This subclass is indented under subclass 81. Processes
including returning a product from a second or subsequent
distillation operation in a series to an earlier distillation
in the series.
SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 99 for mineral oil
distilling apparatus including the combination of a
vaporizer, condensing means with means for returning a part
or all of the condensate to the vaporizer.
208, Mineral Oils: Processes and Products, subclass 355 for
a process of subjecting mineral oils to at least two
distillation operations including returning vapor,
condensate, and/or residue from a later distillation to an
earlier distillation zone.
Subclass:
83
This subclass is indented under subclass 81. Processes
directed to adding water or steam to at least one
distillation operation.
(1) Note. Water or steam is usually added to the
distillation operation to change the relative volatility of
the components of the material being distilled.
Subclass:
84
This subclass is indented under subclass 71. Processes which
includes returning a product from a later distillation
operation to a distillation zone prior to the distillation
zone in which the product was produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
43 for a separatory distillation process in which the
initial residue is extracted with a liquid.
75 78, 82, for other plural distillation processes in which
at least a portion of a product of a second or subsequent
distillation step is returned to a distillation zone prior to
the one in which the product was produced and subclass 98, in
which a separated product of a single separatory distillation
operation is returned to the distillation zone.
SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 99 for mineral oil
distilling apparatus including the combination of a
vaporizing and condensing means with means for returning a
part or all of the condensate to the vaporizer.
208, Mineral Oils: Processes and Products, subclass 355 for
processes in which mineral oil is subjected to at least two
distillation operations in which either vapors, condensate,
and/or residue from a later distillation zone is returned to
an earlier distillation zone.
Subclass:
85
This subclass is indented under subclass 71. Processes
directed to adding water or steam to at least one
distillation operation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
43 for a separatory distillation process in which the
initial residue is extracted with a liquid.
72 76, 79, and 83, for other plural distillation processes in
which water or steam is added.
95 for a single distillation process in which water or steam
is added.
Subclass:
86
This subclass is indented under the class definition.
Processes directed to distilling in a system in which all or
a part thereof is recited as being made of a specific
material.
(1) Note. Processes within the purview of this subclass must
recite only a single distillation step in which the
composition of the system or a part thereof is recited. For
example, broadly distilling using a glass column.
(2) Note. The mere recitation in a claim that an apparatus
is metal does not bring it within the purview of this
subclass, but the recitation in the claim that the column
filling material is chrome steel balls or beryl saddles
does.
SEE OR SEARCH THIS CLASS, SUBCLASS:
6 for a process of adding a material to inhibit or prevent
chemical change which may or may not function to coat the
system.
SEE OR SEARCH CLASS:
55, Gas Separation, 522 for gas separation apparatus in
which the composition of the apparatus is recited.
106, Compositions: Coating or Plastic, appropriate subclass
for a composition for coating the surfaces of the distilling
apparatus.
196, Mineral Oils: Apparatus, subclass 133 for a mineral oil
vaporizing system having some special feature of
construction.
201, Distillation: Processes, Thermolytic, subclass 18 for a
process of destructive distillation utilizing apparatus of a
particular composition.
202, Distillation: Apparatus, subclass 267, in which the
apparatus is recited in terms of the materials of
construction.
266, Metallurgical Apparatus, 280 for the lining
construction for metallurgical receptacles.
520, Synthetic Resins or Natural Rubbers, 1 for a synthetic
resin or a composition containing a synthetic resin for
coating distilling apparatus.
Subclass:
87
This subclass is indented under the class definition.
Processes directed to condensing the vapor evolved during the
distillation step in a plurality of fractions.
(1) Note. To come within the purview of this subclass a
mixed vapor must be produced which is separated into parts by
cooling the vapor in a plurality of distinct stages.
SEE OR SEARCH CLASS:
201, Distillation: Processes, Thermolytic, subclass 30 for a
thermolytic distillation process in which the evolved vapors
are condensed in a plurality of distinct stages.
202, Distillation: Apparatus, subclass 199 for apparatus in
which vapor is passed through a condensate from itself to
surrender high boiling constituents.
208, Mineral Oils: Processes and Products, subclass 342 for
a process including fractionally condensing a mineral oil
containing vapor mixture.
Subclass:
88
This subclass is indented under the class definition.
Processes directed to heating the distilland under pressure
high enough to prevent ebullition and the heated distilland
is then introduced into a zone of lesser pressure resulting
in the volatilizing of at least a portion of the distilland.
SEE OR SEARCH CLASS:
159, Concentrating Evaporators, subclass 2 for a flash
evaporator.
202, Distillation: Apparatus, subclass 177 for a separatory
still with a preheater.
208, Mineral Oils: Processes and Products, subclass 352 and
361 for a process of separating mineral oil wherein the
distilland is heated under pressure high enough to prevent
ebullition and the heated distilland is then introduced into
a zone of lesser pressure.
Subclass:
89
This subclass is indented under the class definition.
Processes directed to introducing the distilland into the
vaporization zone by spreading it as a thin film over a
surface.
(1) Note. The surface on which the distilland is spread may
be liquid, solid or foraminous.
SEE OR SEARCH CLASS:
159, Concentrating Evaporators, 5 for concentrating
apparatus of the film type including subclasses 13+ for
evaporating apparatus designed to maintain the liquid being
evaporated in a film and subclass 49 for an evaporating
process in which the liquid to be concentrated is spread in a
thin film.
196, Mineral Oils: Apparatus, subclass 128 for vaporizing
apparatus for distilling mineral oil in a thin film.
202, Distillation: Apparatus, subclass 236 for separatory
distillation apparatus in which the still has means for
intro- ducing the distilland into the still in the form of a
spray or in the form of a film.
208, Mineral Oils: Processes and Products, subclass 360 for
a process of introducing mineral oil into the vaporization
zone by spreading it as a thin film over a surface. See also
"SEARCH CLASS" thereunder for related fields of search.
Subclass:
90
This subclass is indented under the class definition.
Processes directed to spraying the distilland into the
vaporization zone.
SEE OR SEARCH THIS CLASS, SUBCLASS:
88 for a separatory distillation process in which heated
distilland under pressure is introduced into a zone of lesser
pressure resulting in the volatilization of at least a
portion of the distilland.
SEE OR SEARCH CLASS:
159, Concentrating Evaporators, 48.1 for a process for
concentrating in which the liquid being concentrated is
reduced to a spray; and subclasses 3+ for concentrating
apparatus of the spray type.
202, Distillation: Apparatus, subclass 236 for separatory
distillation apparatus in which the still has means for
intro- ducing the distilland into the still in the form of a
spray.
208, Mineral Oils: Processes and Products, subclass 359 for
a process of distilling mineral oil in which the distilland
is sprayed into the vaporization zone and see "SEARCH CLASS"
thereunder for related fields of search.
Subclass:
91
This subclass is indented under the class definition.
Processes in which distillation is carried out under a
pressure greater than atmospheric or under a vacuum.
(1) Note. The use of pressure varying from atmospheric
changes the relative volatility of the components of the
distilland thereby altering the composition of the vapor
evolved.
SEE OR SEARCH CLASS:
34, Drying and Gas or Vapor Contact With Solids, 402 for a
process of drying a solid involving the application of a
vacuum.
196, Mineral Oils: Apparatus, subclass 114 for mineral oil
vaporizing apparatus operated under vacuum.
201, Distillation: Processes, Thermolytic, subclass 35 for a
process of applying differential pneumatic pressure to the
thermolytic conversion zone.
202, Distillation: Apparatus, subclass 205 for separatory
distillation apparatus provided with means for producing a
vacuum therein and see "SEARCH CLASS" thereunder for related
fields of search.
208, Mineral Oils: Processes and Products, subclass 357 and
366 for a process of distilling mineral oil in which the
vaporization zone is under a pressure greater or less than
atmospheric pressure and see "SEARCH CLASS" under subclass
357 for related fields of search.
588, Hazardous or Toxic Waste Destruction or Containment,
appropriate subclasses for the use of heat or vacuum in the
destruction of hazardous or toxic waste.
Subclass:
92
This subclass is indented under subclass 91. Processes
directed to adding water or steam to the distillation
operation.
(1) Note. Water or steam is usually added to the
distillation operation to change the relative volatility of
the components of the material being distilled.
Subclass:
93
This subclass is indented under subclass 92. Processes
directed to returning a product to the distillation zone.
SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 99 for mineral oil
distilling apparatus including the combination of vaporizing
and condensing means with means for returning a part or all
of the condensate to the vaporizer.
Subclass:
94
This subclass is indented under subclass 91. Processes
directed to returning a product of the distillation operation
to the distillation zone.
(1) Note. To be considered a product of distillation for
purposes of this subclass an overhead vapor or side stream
must be condensed to a liquid before being returned to the
distillation zone. In other words to be considered a
"product" the substance must be isolated outside the
distillation zone.
SEE OR SEARCH CLASS:
208, Mineral Oils: Processes and Products, subclass 358 for
a mineral oil distillation process in which condensate or
residue is returned to the rectification zone after having
been removed therefrom to assist in the separation process.
Subclass:
95
This subclass is indented under the class definition.
Processes directed to adding water or steam to the
distillation operation.
(1) Note. Water or steam is usually added to the
distillation operation to change the relative volatility of
the components of the material being distilled.
SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 126 and 127 for
mineral oil vaporizing apparatus having means to inject gas
or vapor into the vaporization zone.
208, Mineral Oils: Processes and Products, subclass 348, 356
and 362+ for a process in which a gas or vapor is employed to
affect volatilization of the distilland.
588, Hazardous or Toxic Waste Destruction or Containment,
appropriate subclasses wherein the use of water or steam is
used in the destruction of hazardous or toxic waste.
Subclass:
96
This subclass is indented under subclass 95. Processes in
which the water or steam is added to the distillation
column.
Subclass:
97
This subclass is indented under subclass 95. Processes in
which a product of the distillation operation is returned to
the distillation zone.
(1) Note. To be considered a product of distillation for
purposes of this subclass an overhead vapor or side stream
must be condensed to a liquid before being returned to the
distillation zone. In other words to be considered a
"product" the substance must be isolated outside the
distillation zone.
SEE OR SEARCH CLASS:
196, Mineral Oils: Apparatus, subclass 99 for mineral oil
distilling apparatus including the combination of vaporizing
and condensing means with means for returning a part or all
of the condensate to the vaporizer.
208, Mineral Oils: Processes and Products, subclass 358 for
a mineral oil distillation process in which condensate or
residue is returned to the rectification zone after having
been removed therefrom to assist in the vaporization
process.
Subclass:
98
This subclass is indented under the class definition.
Processes directed to returning a product of the distillation
operation to the distillation zone.
(1) Note. To be considered a product of distillation for
purposes of this subclass an overhead vapor or side stream
must be condensed to a liquid before being returned to the
distillation zone. In other words to be considered a
"product" the substance must be isolated outside the
distillation zone.
SEE OR SEARCH THIS CLASS, SUBCLASS:
165 Heat Exchange, subclasses 104.21+ apparatus in which
liquid is vaporized in one zone, condensed in another and the
condensate is returned to the first zone.
196 Mineral Oils: Apparatus, subclass 99 for mineral oil
distilling apparatus including the combination of vaporizing
and condensing means and means for returning a part or all of
the condensate to the vaporizer.
208 Mineral Oils: Processes and Products, subclass 358 for a
mineral oil distillation process in which condensate or
residue is returned to the rectification zone after having
been removed therefrom to assist in the vaporization
process.
Subclass:
99
This subclass is indented under the class definition.
Processes not otherwise provided for.
(1) Note. In this subclass are distillation combinations not
provided for above and not provided for elsewhere.
SEE OR SEARCH CLASS:
23, Chemistry: Physical Processes, subclass 306 for a
process of concentrating a solution of a liquid in a liquid
not otherwise provided for.
99, Foods and Beverages: Apparatus, subclass 78 for a
process of preparing a beverage base in concentrated from and
see "SEARCH THIS CLASS, SUBCLASS" and "SEARCH CLASS"
thereunder for related fields of search.
159, Concentrating Evaporators, 47.1 for a process of
concentrating a liquid, and see "SEARCH CLASS" thereunder for
related fields of search.
208, Mineral Oils: Processes and Products, subclass 347 for
a process of distilling mineral oil not otherwise provided
for.
264, Plastic and Nonmetallic Article Shaping or Treating:
Processes, 405 for a process directed to applying electrical
or wave energy directly to the work.
CROSS-REFERENCE ART COLLECTIONS
The following subclass represents at least a substantial
collection of patents found elsewhere in the classification
of this class which merit isolation for search aid purposes
on specific types of heating.
Subclass:
100
Processes as provided for in this class wherein there is
recited or disclosed a reference to a special type of
heating, such as separation of the vapor by the heating
effect of sonic waves of a specific frequency.
SEE OR SEARCH CLASS:
95, Gas Separation: Processes, 29 for processes of gas
separation in which the separation is effected or enhanced by
use of sound waves.
165, Heat Exchange, appropriate subclasses for apparatus and
processes for the transfer of heat from one material to
another and see "SEARCH CLASS" under the class definition for
related fields of search.
196, Mineral Oils: Apparatus, 120 for mineral oil vaporizing
apparatus having special means for heating.
202, Distillation: Apparatus, subclass 234 for distillation
apparatus using radiant heat or electric heating elements.
210, Liquid Purification or Separation, subclass 738 and 748
for a process of separating liquid mixtures using pulsations
or oscillations.
432, Heating, 1 for a process of heating or heater,
operation not elsewhere provided for.
Information Products Division -- Contacts
Questions regarding this report should be directed to:
U.S. Patent and Trademark Office
Information Products Division
PK3- Suite 441
Washington, DC 20231
tel: (703) 306-2600
FAX: (703) 306-2737
email: oeip@uspto.gov
Last Modified: 6 October 2000