C
SECTION C — CHEMISTRY AND METALLURGY
  
CHEMISTRY
 C01
INORGANIC CHEMISTRY (obtaining metal compounds by metallurgical processes C21B, C22B; production of non-metallic elements or inorganic compounds by electrolysis or electrophoresis C25B)
 C01C
AMMONIA AND CYANOGEN AND THEIR COMPOUNDS (C01B takes precedence in respect of salts of oxyacids of halogens C01B 11/00; peroxides, persalts C01B 15/00; compounds containing selenium or tellurium C01B 19/00; azides C01B 21/08; imido and amido compounds other than cyanamide and its salts C01B 21/10; nitrites C01B 21/50; phosphides C01B 25/08; salts of oxyacids of phosphorus C01B 25/16; arsenic C01B 27/00; antimony C01B 29/00, silicates C01B 33/20; boron C01B 35/00)
 C01C 1/00
Ammonia; Compounds thereof (C01C 3/08, C01C 3/14, C01C 3/16, C01C 3/20 take precedence)
 C01C 1/02
·  Preparation or separation of ammonia
 C01C 1/04
·  ·  Preparation of ammonia by synthesis (preparation or purification of gas mixtures for ammonia synthesis C01B 2/30)
 C01C 1/08
·  ·  Preparation of ammonia from nitrogenous organic substances
 C01C 1/10
·  ·  Separation of ammonia from ammonia liquors, e.g. gas liquors
 C01C 1/12
·  ·  Separation of ammonia from gases and vapours
 C01C 1/14
·  ·  ·  Saturators
 C01C 1/16
·  Halides of ammonium
 C01C 1/18
·  Nitrates of ammonium
 C01C 1/20
·  Sulphides; Polysulphides
 C01C 1/22
·  Sulphites of ammonium
 C01C 1/24
·  Sulphates of ammonium (C01C 1/14 takes precedence)
 C01C 1/242
·  ·  Preparation from ammonia and sulphuric acid or sulphur trioxide  [2]
 C01C 1/244
·  ·  Preparation by double decompostion of ammonium salts with sulphates  [2]
 C01C 1/245
·  ·  Preparation from compounds containing nitrogen and sulphur  [2]
 C01C 1/246
·  ·  ·  from sulphur-containing ammonium compounds  [2]
 C01C 1/247
·  ·  ·  ·  by oxidation with free oxygen  [2]
 C01C 1/248
·  ·  Preventing coalescing or controlling form or size of crystals  [2]
 C01C 1/249
·  ·  Deacidifying the crystals  [2]
 C01C 1/26
·  Carbonates or bicarbonates of ammonium
 C01C 1/28
·  Methods of preparing ammonium salts in general
 C01C 1/28

Note(s)

Salts of polybasic acids with ammonium and a metal as cations are classified as though the ammonium were hydrogen. Ammonium salts of complex acids (other than complex cyanides) which contain a metal in the anion are classified in the relevant groups in C01D-C01G according to the metal; complex ammine salts are also classified in the relevant groups in C01D-C01G according to the metal.

 C01C 3/00
Cyanogen; Compounds thereof
 C01C 3/02
·  Preparation of hydrogen cyanide
 C01C 3/04
·  ·  Separation from gases
 C01C 3/06
·  Stabilisation of hydrogen cyanide
 C01C 3/08
·  Simple or complex cyanides of metals
 C01C 3/10
·  ·  Simple alkali metal cyanides (C01C 3/12 takes precedence)
 C01C 3/11
·  ·  Complex cyanides (C01C 3/12 takes precedence)  [2]
 C01C 3/12
·  ·  Simple or complex iron cyanides
 C01C 3/14
·  Cyanic acid; Salts thereof
 C01C 3/16
·  Cyanamide; Salts thereof (dicyandiamide C07C 129/14)
 C01C 3/18
·  ·  Calcium cyanamide
 C01C 3/20
·  Thiocyanic acid; Salts thereof