Electrolytic or electrophoretic processes for the production of inorganic compounds, non-metals or organic compounds.

Cells or assemblies of cells and their constructions.

Electrodes, diaphragms.

Operating or servicing of cells.

Reversible fuel cells that act as electrolysers are classified in H01M 8/18.

Multi-step processes for surface treatment of metallic material involving at least one process provided for in class C23 and at least one process provided for in class C25 are classified in group C23F 17/00.

Compounds of particular interest are also classified in the relevant classes, C01(inorganic chemistry), C07 (organic chemistry) and C08 (organic macromolecular compounds). The electrolytic or electrophoretic purification of materials is classified according to the nature of the liquid in the relevant places, e.g. A01K 63/00, C02F 1/46, C25B 15/08, C25D 21/16, C25F 7/02.

Cold fusion methods as such are classified in G21B 3/00, but electrodes and cells for cold fusion are further classified in C25B.

An electrothermal treatment of ores or metallurgical products for obtaining metals or alloys is classified in C22B 4/00 and does not involve an electrolytic process.

Alloys as such, prepared by electrolytic methods are classified in C22C.

C25B concerns the production of compounds or non-metals, which includes separating the said products as such, or at least the possibility of separating them.

Illustrative examples:

As a consequence, the electrolytic cells and parts of cells in example (1) are covered by C25B as well, while the electrolytic cells and parts of cells in example (2) are not.

There are, of course, cases that are covered by C25B and another subclass or subgroup.

Electrolytic production of all those inorganic compounds or non-metals that do not fall within the scope of one of the subgroups of C25B 1/00.

Specific compounds like hydrogen, oxygen, silicon, ozone, alkali metal compounds, inorganic acid, per-compounds, etc. are classified in the subgroups of C25B 1/00, not in C25B 1/00.

Electrolytic production of hydrogen or oxygen.

Only the details of the electrolytic production process present in the document are classified.

A simple reference to the presence of an electrolytic cell or hydrogen produced by electrolysis does not justify classification in C25B.

Electrolysis of water with production of hydrogen and oxygen from water at the anode and cathode, even when this water comprises an electroconductive additive, such as a hydroxide or an acid.

Steam electrolysis is also covered.

Production of dissolved species for treating of water or waste water by electrochemical methods, cells and electrodes therefor is classified in C02F 1/467.

Production of dissolved species for treating of water or waste water by electrochemical methods, cells and electrodes therefor is classified in C02F 1/467.

Electrolytic production of per-compounds (see Glossary of terms).

Treatment of water and waste water by electrochemical disinfection is classified in C02F 1/4672.

Photoelectrolysis process only.

Distinctions should be drawn among a (1) photoelectrolytic process (C25B 1/55), (2) cell with two electrodes, even without externally applied voltage (C25B 9/50), and (3) photolytic process or cell with a single electrode where the process is catalyzed by a substance producing photoelectrons (B01J 19/12 - B01J 19/129).

Production of organic compounds by an electrolytic reaction.

Processes that generate electricity and produce a compound other than water, e.g. hydrogen peroxide.

Production of compounds or non-metals where the process includes a step of reduction or oxidation of the material from which the compound or non-metals is formed, e.g. formation of a polymer.

Cells, assembly of cells or assemblies of constructional parts used for the electrolytic production processes that are defined in other subgroups of C25B.

Devices for the electrolytic treatment of water or sewage are classified in C02F 1/46104.

Cells subjected to pressure that exceeds ambient pressure, e.g. high-pressure water electrolysis system.

Cells and their construction comprising electrodes that are not sacrificial.

Membrane-electrode assemblies (MEA).

Electrodes that move in space or around an axis, such as rotary electrodes.

Electrodes that comprise a bed of electrically conductive particles that are arranged such that they at least temporarily contact each other and an electrical conductor (a net, a plate etc.) that provides connection to a power source.

Electrodes in particulate form for treatment of water, waste water or sewage are classified in C02F 1/46114.

Electrodes that comprise a bed of electrically conductive particles that are arranged such that they are in motion and temporarily contact each other and an electrical conductor (a net, a plate etc.) that provides connection to a power source.

Electrodes that comprise a bed of electrically conductive particles that are arranged such that they are at rest and continuously touch each other and an electrical conductor (a net, a plate etc.) that provides connection to a power source.

Devices and connections that are monopolar.

Stacks of a plurality of cells with bipolar electrodes, as in a filter press.

Cells with a diaphragm, e.g. membrane or separator, which is a permeable barrier between electrodes.

Electrodes used for the electrolytic or electrochemical production processes that are defined somewhere in C25B.

Electrodes for treatment of water or sewage are classified in C02F 1/46109.

Special forms of electrodes, such a Venetian blinds, expandable electrodes.

Perforated or foraminous structures, e.g. expandable metal.

Electrodes that have a carbon-based structure, e.g. carbon cloth.

Diamond electrodes used in treatment of water or waste water etc. are classified in C02F 1/46109 and C02F 2001/46133.

Structural material used to separate the electrodes of an electrolytic or electrophoretic cell to form two or more compartments and allow the flow of an electrolytic solution or the migration of particular ions while preventing the intermixing of the products formed at the surface of the electrodes.

Organic polymer membranes, when the emphasis is on the polymer electrolyte compound, are classified in C08J 5/22 and in H01M 8/1018 or H01M 2300/0082 if the polymer electrolyte compound is used in fuel cells.

Operating or servicing of cells when generally applied to a cell or in a process of C25B.

When related to a specific process only, the operating or servicing is classified with the process, e.g. decomposition of amalgam, which is process-related and therefore classified in C25B 1/42.

Regulation of the inter-electrode distance in electrochemical machining, electrolytic grinding and electro-erosion is classified in B23H.