C
SECTION C — CHEMISTRY; METALLURGY
 C

Note(s)

In section C, the definitions of groups of chemical elements are as follows:

  • Alkali metals: Li, Na, K, Rb, Cs, Fr
  • Alkaline earth metals: Ca, Sr, Ba, Ra
  • Lanthanides: elements with atomic numbers 57 to 71 inclusive
  • Rare earths: Sc, Y, Lanthanides
  • Actinides: elements with atomic numbers 89 to 103 inclusive
  • Refractory metals: Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W
  • Halogens: F, Cl, Br, I, At
  • Noble gases: He, Ne, Ar, Kr, Xe, Rn
  • Platinum group: Os, Ir, Pt, Ru, Rh, Pd
  • Noble metals: Ag, Au, Platinum group
  • Light metals: alkali metals, alkaline earth metals, Be, Al, Mg
  • Heavy metals: metals other than light metals
  • Iron group: Fe, Co, Ni
  • Non-metals: H, B, C, Si, N, P, O, S, Se, Te, noble gases, halogens
  • Metals: elements other than non-metals
  • Transition elements: elements with atomic numbers 21 to 30 inclusive, 39 to 48 inclusive, 57 to 80 inclusive, 89 upwards

  
METALLURGY
 C25
ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR (electrodialysis, electro-osmosis, separation of liquids by electricity B01D; working of metal by the action of a high concentration of electric current B23H; surface treatment of metallic material or coating involving at least one process provided for in class C23 and at least one process covered by this class C23C 28/00, C23F 17/00; anodic or cathodic protection C23F; single-crystal growth C30B; electrochemical methods of analysis G01N; electrochemical measuring, indicating or recording devices G01R; electrolytic circuit elements, e.g. capacitors, H01G; electrochemical current or voltage generators H01M)  [4]
 C25

Note(s)

  1. Inventions dealing with electrolytic or electrophoretic processes or apparatus or operational features are classified
    1. in the groups for the compounds or articles produced, and [2]
    2. in the groups which cover the apparatus or operational features. [2]
  2. 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[2]
 C25C
PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR  [2]
 C25C 1/00
Electrolytic production, recovery or refining of metals by electrolysis of solutions (C25C 5/00 takes precedence)  [2]
 C25C 1/02
·  of light metals  [2]
 C25C 1/04
·  ·  in mercury cathode cells  [2]
 C25C 1/06
·  of iron group metals, refractory metals or manganese  [2]
 C25C 1/08
·  ·  of nickel or cobalt  [2]
 C25C 1/10
·  ·  of chromium or manganese  [2]
 C25C 1/12
·  of copper  [2]
 C25C 1/14
·  of tin  [2]
 C25C 1/16
·  of zinc, cadmium or mercury  [2]
 C25C 1/18
·  of lead  [2]
 C25C 1/20
·  of noble metals  [2]
 C25C 1/22
·  of metals not provided for in groups C25C 1/02-C25C 1/20  [2]
 C25C 1/24
·  Alloys obtained by cathodic reduction of all their ions  [2]
 C25C 3/00
Electrolytic production, recovery or refining of metals by electrolysis of melts (C25C 5/00 takes precedence)  [2]
 C25C 3/02
·  of alkali or alkaline earth metals  [2]
 C25C 3/04
·  of magnesium  [2]
 C25C 3/06
·  of aluminium  [2]
 C25C 3/08
·  ·  Cell construction, e.g. bottoms, walls  [2]
 C25C 3/10
·  ·  ·  External supporting frames or structures  [2]
 C25C 3/12
·  ·  ·  Anodes  [2]
 C25C 3/14
·  ·  Devices for feeding or crust breaking  [2]
 C25C 3/16
·  ·  Electric current supply devices, e.g. bus bars  [2]
 C25C 3/18
·  ·  Electrolytes  [2]
 C25C 3/20
·  ·  Automatic control or regulation of cells (controlling or regulating per se G05)  [2]
 C25C 3/22
·  ·  Collecting emitted gases  [2]
 C25C 3/24
·  ·  Refining  [2]
 C25C 3/26
·  of titanium, zirconium, hafnium, tantalum or vanadium  [2]
 C25C 3/28
·  ·  of titanium  [2]
 C25C 3/30
·  of manganese  [2]
 C25C 3/32
·  of chromium  [2]
 C25C 3/34
·  of metals not provided for in groups C25C 3/02-C25C 3/32  [2]
 C25C 3/36
·  Alloys obtained by cathodic reduction of all their ions  [2]
 C25C 5/00
Electrolytic production, recovery or refining of metal powders or porous metal masses  [2]
 C25C 5/02
·  from solutions  [2]
 C25C 5/04
·  from melts  [2]
 C25C 7/00
Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells (for the production of aluminium C25C 3/06-C25C 3/22)  [2]
 C25C 7/02
·  Electrodes (consumable anodes for the refining of metals C25C 1/00-C25C 5/00); Connections thereof  [2]
 C25C 7/04
·  Diaphragms; Spacing elements  [2]
 C25C 7/06
·  Operating or servicing  [2]
 C25C 7/08
·  ·  Separating of deposited metals from the cathode  [2]