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

  
CHEMISTRY
 C01
INORGANIC CHEMISTRY (fermentation or enzyme-using processes for the preparation of elements or inorganic compounds except carbon dioxide C12P 3/00; obtaining metal compounds from mixtures, e.g. ores, which are intermediate compounds in a metallurgical process for obtaining a free metal C21B, C22B; production of non-metallic elements or inorganic compounds by electrolysis or electrophoresis C25B)
 C01

Note(s)

In this class, in the absence of an indication to the contrary, a compound is classified in the last appropriate place. [3]

 C01B
NON-METALLIC ELEMENTS; COMPOUNDS THEREOF
 C01B

Note(s)

Attention is drawn to the definitions of groups of chemical elements following the title of section C. [3]

 C01B 3/00 - 
C01B 6/00
Hydrogen; Hydrides; Water; Synthesis gas from hydrocarbons
 C01B 3/00
Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it (separation of gases by physical means B01D); Purification of hydrogen (production of water-gas and synthesis gas from solid carbonaceous material C10J; purifying or modifying the chemical compositions of combustible technical gases containing carbon monoxide C10K)  [3]
 C01B 3/02
·  Production of hydrogen or of gaseous mixtures containing hydrogen  [3]
 C01B 3/04
·  ·  by decomposition of inorganic compounds, e.g. ammonia  [3]
 C01B 3/06
·  ·  by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents (by electrolysis of water C25B 1/04)  [3]
 C01B 3/08
·  ·  ·  with metals  [3]
 C01B 3/10
·  ·  ·  ·  by reaction of water vapour with metals  [3]
 C01B 3/12
·  ·  ·  by reaction of water vapour with carbon monoxide  [3]
 C01B 3/14
·  ·  ·  ·  Handling of heat and steam  [3]
 C01B 3/16
·  ·  ·  ·  using catalysts  [3]
 C01B 3/18
·  ·  ·  ·  using moving solid particles  [3]
 C01B 3/20
·  ·  ·  by reaction of metal hydroxides with carbon monoxide  [3]
 C01B 3/22
·  ·  by decomposition of gaseous or liquid organic compounds (coking liquid carbonaceous materials C10B 55/00)  [3]
 C01B 3/24
·  ·  ·  of hydrocarbons  [3]
 C01B 3/26
·  ·  ·  ·  using catalysts  [3]
 C01B 3/28
·  ·  ·  ·  using moving solid particles  [3]
 C01B 3/30
·  ·  ·  ·  ·  using the fluidised bed technique  [3]
 C01B 3/32
·  ·  by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air  [3]
 C01B 3/34
·  ·  ·  by reaction of hydrocarbons with gasifying agents  [3]
 C01B 3/36
·  ·  ·  ·  using oxygen or mixtures containing oxygen as gasifying agents  [3]
 C01B 3/38
·  ·  ·  ·  using catalysts  [3]
 C01B 3/40
·  ·  ·  ·  ·  characterised by the catalyst  [3]
 C01B 3/42
·  ·  ·  ·  ·  using moving solid particles  [3]
 C01B 3/44
·  ·  ·  ·  ·  ·  using the fluidised bed technique  [3]
 C01B 3/46
·  ·  ·  ·  using discontinuously preheated non-moving solid materials, e.g. blast and run  [3]
 C01B 3/48
·  ·  ·  ·  followed by reaction of water vapour with carbon monoxide  [3]
 C01B 3/50
·  Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification (C01B 3/14 takes precedence)  [3]
 C01B 3/52
·  ·  by contacting with liquids; Regeneration of used liquids  [3]
 C01B 3/54
·  ·  ·  including a catalytic reaction  [3]
 C01B 3/56
·  ·  by contacting with solids; Regeneration of used solids  [3]
 C01B 3/58
·  ·  ·  including a catalytic reaction  [3]
 C01B 4/00
Hydrogen isotopes; Inorganic compounds thereof prepared by isotope exchange, e.g. NH3+D2 NH2D+HD (separation of isotopes B01D 59/00; other chemical reactions to form compounds of hydrogen isotopes, see the relevant groups for hydrogen compounds in class C01)  [2]
 C01B 5/00
Water
 C01B 5/02
·  Heavy water; Preparation by chemical reaction of hydrogen isotopes or their compounds, e.g. 4ND3+7O2 4NO2+6D2O, 2D2 +O2 2D2O
 C01B 6/00
Hydrides of metals; Monoborane or diborane; Addition complexes thereof (higher hydrides of boron, substituted hydrides of boron C01B 35/00)  [2]
 C01B 6/02
·  Hydrides of transition elements; Addition complexes thereof
 C01B 6/04
·  Hydrides of alkali metals, alkaline earth metals, beryllium or magnesium; Addition complexes thereof
 C01B 6/06
·  Hydrides of aluminium, gallium, indium, thallium, germanium, tin, lead, arsenic, antimony, bismuth or polonium; Monoborane; Diborane; Addition complexes thereof
 C01B 6/10
·  ·  Monoborane; Diborane; Addition complexes thereof  [2]
 C01B 6/11
·  ·  ·  Preparation from boron or inorganic compounds containing boron and oxygen  [2]
 C01B 6/13
·  ·  ·  Addition complexes of monoborane or diborane, e.g. with phosphine, arsine or hydrazine  [2]
 C01B 6/15
·  ·  ·  ·  Metal boranates; Addition complexes thereof  [2]
 C01B 6/17
·  ·  ·  ·  ·  Preparation from boron or inorganic compounds containing boron and oxygen  [2]
 C01B 6/19
·  ·  ·  ·  ·  Preparation from other compounds of boron  [2]
 C01B 6/21
·  ·  ·  ·  ·  ·  Preparation of boranates of alkali metals, alkaline earth metals, magnesium or beryllium; Addition complexes thereof, e.g. LiBH4.2N2H4, NaB2H7  [2]
 C01B 6/23
·  ·  ·  ·  ·  ·  Preparation of boranates of other metals, e.g. aluminium borohydride; Addition complexes thereof, e.g. Li[Al(BH4)3H]  [2]
 C01B 6/24
·  Hydrides containing at least two metals, e.g. Li(AlH4); Addition complexes thereof (C01B 6/13-C01B 6/23 take precedence)  [2]
 C01B 6/26
·  ·  Preparation from the metal with the highest valency or from its oxides or salts of its oxyacids
 C01B 6/34
·  Purification; Stabilisation
 C01B 7/00 - 
C01B 11/00
Halogens; Compounds thereof
 C01B 7/00
Halogens; Halogen acids (oxyacids C01B 11/00)
 C01B 7/01
·  Chlorine; Hydrogen chloride  [2]
 C01B 7/03
·  ·  Preparation from chlorides  [3]
 C01B 7/04
·  ·  ·  Preparation of chlorine from hydrogen chloride  [3]
 C01B 7/05
·  ·  ·  Preparation from ammonium chloride  [3]
 C01B 7/07
·  ·  Purification  [3]
 C01B 7/075
·  ·  ·  of liquid chlorine  [3]
 C01B 7/09
·  Bromine; Hydrogen bromide  [2]
 C01B 7/13
·  Iodine; Hydrogen iodide  [2]
 C01B 7/14
·  ·  Iodine  [2]
 C01B 7/16
·  ·  ·  Preparation from seaweed  [2]
 C01B 7/19
·  Fluorine; Hydrogen fluoride  [2]
 C01B 7/20
·  ·  Fluorine  [2]
 C01B 7/24
·  Inter-halogen compounds
 C01B 9/00
General methods of preparing halides (particular individual halides, see the relevant groups in subclasses C01B-C01G according to the element combined with the halogen; electrolytic production of inorganic compounds C25B)
 C01B 9/02
·  chlorides
 C01B 9/04
·  bromides
 C01B 9/06
·  iodides
 C01B 9/08
·  fluorides
 C01B 11/00
Oxides or oxyacids of halogens; Salts thereof
 C01B 11/02
·  Oxides of chlorine
 C01B 11/04
·  Hypochlorous acid
 C01B 11/06
·  ·  Hypochlorites, e.g. chlorinated lime
 C01B 11/08
·  Chlorous acid
 C01B 11/10
·  ·  Chlorites
 C01B 11/12
·  Chloric acid
 C01B 11/14
·  ·  Chlorates
 C01B 11/16
·  Perchloric acid
 C01B 11/18
·  ·  Perchlorates
 C01B 11/20
·  Oxygen compounds of bromine
 C01B 11/22
·  Oxygen compounds of iodine
 C01B 11/24
·  Oxygen compounds of fluorine
 C01B 13/00 - 
C01B 15/00
Oxygen; Oxides or hydroxides in general; Per-compounds
 C01B 13/00
Oxygen; Ozone; Oxides or hydroxides in general
 C01B 13/02
·  Preparation of oxygen (by liquefying F25J)
 C01B 13/08
·  ·  from air with the aid of metal oxides, e.g. barium oxide, manganese oxide
 C01B 13/10
·  Preparation of ozone
 C01B 13/11
·  ·  by electric discharge  [2]
 C01B 13/14
·  Methods for preparing oxides or hydroxides in general (particular individual oxides or hydroxides, see the relevant groups of subclasses C01B-C01G or C25B, according to the element combined with the oxygen or hydroxyl)
 C01B 13/16
·  ·  Purification  [3]
 C01B 13/18
·  ·  by thermal decomposition of compounds, e.g. of salts or hydroxides  [3]
 C01B 13/20
·  ·  by oxidation of elements in the gaseous state; by oxidation or hydrolysis of compounds in the gaseous state  [3]
 C01B 13/22
·  ·  ·  of halides or oxyhalides  [3]
 C01B 13/24
·  ·  ·  ·  in the presence of hot combustion gases  [3]
 C01B 13/26
·  ·  ·  ·  in the presence of a fluidised bed  [3]
 C01B 13/28
·  ·  ·  ·  using a plasma or an electric discharge  [3]
 C01B 13/30
·  ·  ·  ·  Removal and cooling of the oxide containing suspension  [3]
 C01B 13/32
·  ·  by oxidation or hydrolysis of elements or compounds in the liquid or solid state  [3]
 C01B 13/34
·  ·  by oxidation or hydrolysis of sprayed or atomised solutions  [3]
 C01B 13/36
·  ·  by precipitation reactions in solutions  [3]
 C01B 15/00
Peroxides; Peroxyhydrates; Peroxyacids or salts thereof; Superoxides; Ozonides
 C01B 15/01
·  Hydrogen peroxide  [3]
 C01B 15/013
·  ·  Separation; Purification; Concentration  [3]
 C01B 15/017
·  ·  ·  Anhydrous hydrogen peroxide; Anhydrous solutions or gaseous mixtures containing hydrogen peroxide  [3]
 C01B 15/022
·  ·  Preparation from organic compounds  [2]
 C01B 15/023
·  ·  ·  by the alkyl-anthraquinone process  [3]
 C01B 15/024
·  ·  ·  from hydrocarbons  [3]
 C01B 15/026
·  ·  ·  from alcohols  [3]
 C01B 15/027
·  ·  Preparation from water  [3]
 C01B 15/029
·  ·  Preparation from hydrogen and oxygen  [3]
 C01B 15/03
·  ·  Preparation from inorganic peroxy-compounds, e.g. from peroxysulphates  [3]
 C01B 15/032
·  ·  ·  from metal peroxides  [3]
 C01B 15/037
·  ·  Stabilisation by additives  [3]
 C01B 15/04
·  Metal peroxides or peroxyhydrates thereof; Superoxides; Ozonides  [3]
 C01B 15/043
·  ·  of alkali metals, alkaline earth metals or of magnesium  [3]
 C01B 15/047
·  ·  of heavy metals  [3]
 C01B 15/055
·  Peroxyhydrates (C01B 15/04 takes precedence); Peroxyacids or salts thereof  [3]
 C01B 15/06
·  ·  containing sulphur  [3]
 C01B 15/08
·  ·  ·  Peroxysulphates  [3]
 C01B 15/10
·  ·  containing carbon  [3]
 C01B 15/12
·  ·  containing boron  [3]
 C01B 15/14
·  ·  containing silicon  [3]
 C01B 15/16
·  ·  containing phosphorus  [3]
 C01B 17/00
Sulphur; Compounds thereof
 C01B 17/02
·  Preparation of sulphur; Purification
 C01B 17/027
·  ·  Recovery of sulphur from material containing elemental sulphur, e.g. luxmasses; Purification  [3]
 C01B 17/033
·  ·  ·  using a liquid extractant  [3]
 C01B 17/04
·  ·  from gaseous sulphur compounds including gaseous sulphides
 C01B 17/05
·  ·  ·  by wet processes  [3]
 C01B 17/06
·  ·  from non-gaseous sulphides or materials containing such sulphides, e.g. ores
 C01B 17/10
·  ·  Finely-divided sulphur, e.g. sublimed sulphur, flowers of sulphur
 C01B 17/12
·  ·  Insoluble sulphur (-sulphur)
 C01B 17/16
·  Hydrogen sulphides
 C01B 17/18
·  ·  Hydrogen polysulphides
 C01B 17/20
·  Methods for preparing sulphides or polysulphides, in general (ammonium sulphides or polysulphides C01C; sulphides or polysulphides of metals, other than alkali metals, magnesium, calcium, strontium, and barium, see the relevant groups of subclasses C01F or C01G, according to the metal)
 C01B 17/22
·  Alkali metal sulphides or polysulphides
 C01B 17/24
·  ·  Preparation by reduction
 C01B 17/26
·  ·  ·  with carbon
 C01B 17/28
·  ·  ·  with reducing gases
 C01B 17/30
·  ·  Preparation from sodium or potassium amalgam with sulphur or sulphides
 C01B 17/32
·  ·  Hydrosulphides of sodium or potassium
 C01B 17/34
·  ·  Polysulphides of sodium or potassium
 C01B 17/36
·  ·  Purification
 C01B 17/38
·  ·  Dehydration
 C01B 17/40
·  ·  Making shaped products, e.g. granules
 C01B 17/42
·  Sulphides or polysulphides of magnesium, calcium, strontium, or barium
 C01B 17/43
·  ·  from oxides or hydroxides with sulphur or hydrogen sulphide
 C01B 17/44
·  ·  by reduction of sulphates
 C01B 17/45
·  Compounds containing sulphur and halogen, with or without oxygen
 C01B 17/46
·  Compounds containing sulphur, halogen, hydrogen, and oxygen
 C01B 17/48
·  Sulphur dioxide; Sulphurous acid
 C01B 17/50
·  ·  Preparation of sulphur dioxide
 C01B 17/52
·  ·  ·  by roasting sulphides (C22B 1/00 takes precedence)
 C01B 17/54
·  ·  ·  by burning elemental sulphur
 C01B 17/56
·  ·  ·  Separation; Purification
 C01B 17/58
·  ·  ·  Recovery of sulphur dioxide from acid tar and the like
 C01B 17/60
·  ·  ·  Isolation of sulphur dioxide from gases
 C01B 17/62
·  Methods of preparing sulphites in general (particular individual sulphites, see the relevant groups of subclasses C01B-C01G, according to the cation)
 C01B 17/64
·  Thiosulphates; Dithionites; Polythionates
 C01B 17/66
·  ·  Dithionites
 C01B 17/69
·  Sulphur trioxide; Sulphuric acid  [3]
 C01B 17/70
·  ·  Stabilisation of gamma-form sulphur trioxide
 C01B 17/74
·  ·  Preparation  [3]
 C01B 17/76
·  ·  ·  by contact processes
 C01B 17/765
·  ·  ·  ·  Multi-stage SO3-conversion  [3]
 C01B 17/77
·  ·  ·  ·  Fluidised-bed processes  [3]
 C01B 17/775
·  ·  ·  ·  Liquid phase contacting processes or wet catalysis processes  [3]
 C01B 17/78
·  ·  ·  ·  characterised by the catalyst used
 C01B 17/79
·  ·  ·  ·  ·  containing vanadium  [3]
 C01B 17/80
·  ·  ·  ·  Apparatus
 C01B 17/82
·  ·  ·  of sulphuric acid using a nitrogen oxide process
 C01B 17/84
·  ·  ·  ·  chamber process
 C01B 17/86
·  ·  ·  ·  tower process
 C01B 17/88
·  ·  Concentration of sulphuric acid
 C01B 17/90
·  ·  Separation; Purification
 C01B 17/92
·  ·  ·  Recovery from acid tar and the like
 C01B 17/94
·  ·  ·  Recovery from nitration acids
 C01B 17/96
·  Methods for the preparation of sulphates in general (particular individual sulphates, see the relevant groups of subclasses C01B-C01G, according to the cation)
 C01B 17/98
·  Other compounds containing sulphur and oxygen (persulphuric acids C01B 15/06; persulphates C01B 15/08)
 C01B 19/00
Selenium; Tellurium; Compounds thereof (phosphorus compounds C01B 25/14)
 C01B 19/02
·  Elemental selenium or tellurium  [3]
 C01B 19/04
·  Binary compounds  [3]
 C01B 21/00
Nitrogen; Compounds thereof
 C01B 21/02
·  Preparation of nitrogen (from ammonia C01B 3/04)
 C01B 21/04
·  Purification or separation of nitrogen (by liquefying F25J)
 C01B 21/06
·  Binary compounds of nitrogen with metals, with silicon, or with boron (azides C01B 21/08)
 C01B 21/064
·  ·  with boron  [3]
 C01B 21/068
·  ·  with silicon  [3]
 C01B 21/072
·  ·  with aluminium  [3]
 C01B 21/076
·  ·  with titanium or zirconium  [3]
 C01B 21/08
·  Hydrazoic acid; Azides; Halogen azides
 C01B 21/082
·  Compounds containing nitrogen and non-metals (C01B 21/06, C01B 21/08 take precedence)  [3]
 C01B 21/083
·  ·  containing one or more halogen atoms  [3]
 C01B 21/084
·  ·  ·  containing also one or more oxygen atoms, e.g. nitrosyl halides  [3]
 C01B 21/086
·  ·  containing one or more sulphur atoms  [3]
 C01B 21/087
·  ·  containing one or more hydrogen atoms  [3]
 C01B 21/088
·  ·  ·  containing also one or more halogen atoms  [3]
 C01B 21/09
·  ·  ·  ·  Halogeno-amines, e.g. chloramine  [3]
 C01B 21/092
·  ·  ·  containing also one or more metal atoms  [3]
 C01B 21/093
·  ·  ·  containing also one or more sulphur atoms  [3]
 C01B 21/094
·  ·  ·  ·  Nitrosyl containing acids  [3]
 C01B 21/096
·  ·  ·  ·  Amidosulphonic acid; Salts thereof  [3]
 C01B 21/097
·  ·  containing phosphorus atoms  [3]
 C01B 21/098
·  ·  ·  Phosphonitrilic dihalides; Polymers thereof  [3]
 C01B 21/12
·  ·  Carbamic acid; Salts thereof
 C01B 21/14
·  ·  Hydroxylamine; Salts thereof
 C01B 21/16
·  ·  Hydrazine; Salts thereof
 C01B 21/20
·  Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
 C01B 21/22
·  ·  Nitrous oxide (N2O)
 C01B 21/24
·  ·  Nitric oxide (NO)
 C01B 21/26
·  ·  ·  Preparation by catalytic oxidation of ammonia
 C01B 21/28
·  ·  ·  ·  Apparatus
 C01B 21/30
·  ·  ·  Preparation by oxidation of nitrogen
 C01B 21/32
·  ·  ·  ·  Apparatus
 C01B 21/34
·  ·  Nitrogen trioxide (N2O3)
 C01B 21/36
·  ·  Nitrogen dioxide (NO2, N2O4) (C01B 21/26, C01B 21/30 take precedence)
 C01B 21/38
·  ·  Nitric acid
 C01B 21/40
·  ·  ·  Preparation by absorption of oxides of nitrogen
 C01B 21/42
·  ·  ·  Preparation from nitrates
 C01B 21/44
·  ·  ·  Concentration
 C01B 21/46
·  ·  ·  Purification; Separation
 C01B 21/48
·  ·  Methods for the preparation of nitrates in general (particular individual nitrates, see the relevant groups of subclasses C01B-C01G, according to the cation)
 C01B 21/50
·  ·  Nitrous acid; Salts thereof
 C01B 23/00
Noble gases; Compounds thereof; Radon (liquefying F25J)
 C01B 25/00
Phosphorus; Compounds thereof (C01B 21/00, C01B 23/00 take precedence; perphosphates C01B 15/16)  [3]
 C01B 25/01
·  Treating phosphate ores or other raw phosphate materials to obtain phosphorus or phosphorus compounds  [2]
 C01B 25/02
·  Preparation of phosphorus
 C01B 25/023
·  ·  of red phosphorus  [2]
 C01B 25/027
·  ·  of yellow phosphorus  [2]
 C01B 25/04
·  Purification of phosphorus
 C01B 25/043
·  ·  of red phosphorus  [2]
 C01B 25/047
·  ·  of yellow phosphorus  [2]
 C01B 25/06
·  Hydrogen phosphides
 C01B 25/08
·  Other phosphides
 C01B 25/10
·  Halides or oxyhalides of phosphorus  [2]
 C01B 25/12
·  Oxides of phosphorus
 C01B 25/14
·  Sulphur, selenium, or tellurium compounds of phosphorus
 C01B 25/16
·  Oxyacids of phosphorus; Salts thereof (peroxyacids or salts thereof C01B 15/00)
 C01B 25/163
·  ·  Phosphorous acid; Salts thereof  [2]
 C01B 25/165
·  ·  Hypophosphorous acid; Salts thereof  [2]
 C01B 25/168
·  ·  Pyrophosphorous acid; Salts thereof  [2]
 C01B 25/18
·  ·  Phosphoric acid
 C01B 25/20
·  ·  ·  Preparation from elemental phosphorus or phosphoric anhydride
 C01B 25/22
·  ·  ·  Preparation by reacting phosphate containing material with an acid, e.g. wet process
 C01B 25/222
·  ·  ·  ·  with sulphuric acid, a mixture of acids mainly consisting of sulphuric acid or a mixture of compounds forming it in situ, e.g. a mixture of sulphur dioxide, water and oxygen  [3]
 C01B 25/223
·  ·  ·  ·  ·  only one form of calcium sulphate being formed  [3]
 C01B 25/225
·  ·  ·  ·  ·  ·  Dihydrate process  [3]
 C01B 25/226
·  ·  ·  ·  ·  ·  Hemihydrate process  [3]
 C01B 25/228
·  ·  ·  ·  ·  one form of calcium sulphate being formed and then converted to another form  [3]
 C01B 25/229
·  ·  ·  ·  ·  ·  Hemihydrate-dihydrate process  [3]
 C01B 25/231
·  ·  ·  ·  ·  ·  Dihydrate-hemihydrate process  [3]
 C01B 25/232
·  ·  ·  ·  ·  Preparation by reacting phosphate containing material with concentrated sulphuric acid and subsequently lixiviating the obtained mass, e.g. clincker process  [3]
 C01B 25/234
·  ·  ·  Purification; Stabilisation; Concentration (purification concomitant with preparation C01B 25/22; preparation involving solvent-solvent extraction C01B 25/46)  [3]
 C01B 25/235
·  ·  ·  ·  Clarification; Stabilisation to prevent post-precipitation of dissolved impurities  [3]
 C01B 25/237
·  ·  ·  ·  Selective elimination of impurities  [3]
 C01B 25/238
·  ·  ·  ·  ·  Cationic impurities  [3]
 C01B 25/24
·  ·  Condensed phosphoric acids
 C01B 25/26
·  ·  Phosphates (perphosphates C01B 15/16)
 C01B 25/28
·  ·  ·  Ammonium phosphates
 C01B 25/30
·  ·  ·  Alkali metal phosphates
 C01B 25/32
·  ·  ·  Phosphates of magnesium, calcium, strontium, or barium
 C01B 25/34
·  ·  ·  ·  Magnesium phosphates
 C01B 25/36
·  ·  ·  Aluminium phosphates
 C01B 25/37
·  ·  ·  Phosphates of heavy metals  [2]
 C01B 25/38
·  ·  ·  Condensed phosphates
 C01B 25/39
·  ·  ·  ·  of alkali metals  [3]
 C01B 25/40
·  ·  ·  ·  Polyphosphates  [2]
 C01B 25/41
·  ·  ·  ·  ·  of alkali metals  [3]
 C01B 25/42
·  ·  ·  ·  Pyrophosphates  [2]
 C01B 25/44
·  ·  ·  ·  Metaphosphates  [2]
 C01B 25/445
·  ·  ·  ·  ·  of alkali metals  [3]
 C01B 25/45
·  ·  ·  containing plural metal, or metal and ammonium  [3]
 C01B 25/455
·  ·  ·  containing halogen  [3]
 C01B 25/46
·  ·  Preparation involving solvent-solvent extraction (extraction per se B01D 11/00)  [2]
 C01B 31/00
Carbon; Compounds thereof (C01B 21/00, C01B 23/00 take precedence; percarbonates C01B 15/10; carbon black C09C 1/48; gas carbon production C10B)  [3]
 C01B 31/02
·  Preparation of carbon (by using ultra-high pressure, e.g. for the formation of diamonds, B01J 3/06; by crystal growth C30B); Purification
 C01B 31/04
·  ·  Graphite
 C01B 31/06
·  ·  Diamond
 C01B 31/08
·  Active carbon
 C01B 31/10
·  ·  Preparation by using gaseous activating agents
 C01B 31/12
·  ·  Preparation by using non-gaseous activating agents
 C01B 31/14
·  ·  Granulation (apparatus B01J 2/00)
 C01B 31/16
·  Preparation of ion-exchanging materials from carbonaceous material
 C01B 31/18
·  Carbon monoxide (metal carbonyls C01G)
 C01B 31/20
·  Carbon dioxide
 C01B 31/22
·  ·  Solidifying
 C01B 31/24
·  Methods for the preparation of carbonates or bicarbonates in general (percarbonates C01B 15/10; particular individual carbonates, see the relevant groups of subclasses C01B-C01G, according to the cation)
 C01B 31/26
·  Compounds containing carbon and sulphur, e.g. carbon disulphide, carbon oxysulphide; Thiophosgene
 C01B 31/28
·  Phosgene
 C01B 31/30
·  Carbides (alloys C22)
 C01B 31/32
·  ·  Calcium carbide
 C01B 31/34
·  ·  Tungsten or molybdenum carbides
 C01B 31/36
·  ·  Carbides of silicon or boron
 C01B 33/00
Silicon; Compounds thereof (C01B 21/00, C01B 23/00 take precedence; persilicates C01B 15/14; carbides C01B 31/36)  [3]
 C01B 33/02
·  Silicon (forming a single crystal layer from the vapour phase C30B 25/00)
 C01B 33/04
·  Hydrides of silicon
 C01B 33/06
·  Metal silicides (alloys C22)
 C01B 33/08
·  Compounds containing halogen
 C01B 33/10
·  ·  Compounds containing silicon, fluorine, and other elements
 C01B 33/107
·  ·  Halogenated silanes  [3]
 C01B 33/113
·  Silicon oxides; Hydrates thereof  [3]
 C01B 33/12
·  ·  Silica; Hydrates thereof, e.g. lepidoic silicic acid  [3]
 C01B 33/14
·  ·  ·  Colloidal silica, e.g. dispersions, gels, sols  [3]
 C01B 33/141
·  ·  ·  ·  Preparation of hydrosols or aqueous dispersions  [3]
 C01B 33/142
·  ·  ·  ·  ·  by acidic treatment of silicates  [3]
 C01B 33/143
·  ·  ·  ·  ·  ·  of aqueous solutions of silicates  [3]
 C01B 33/145
·  ·  ·  ·  Preparation of hydroorganosols, organosols or dispersions in an organic medium  [3]
 C01B 33/146
·  ·  ·  ·  After-treatment of sols (preparation of hydroorganosols, organosols or dispersions in an organic medium from hydrosols C01B 33/145)  [3]
 C01B 33/148
·  ·  ·  ·  ·  Concentration; Drying; Dehydration; Stabilisation; Purification  [3]
 C01B 33/149
·  ·  ·  ·  ·  Coating  [3]
 C01B 33/151
·  ·  ·  ·  ·  by progressively adding a sol to a different sol, i.e. "build up" of particles using a "heel"  [3]
 C01B 33/152
·  ·  ·  ·  Preparation of hydrogels  [3]
 C01B 33/154
·  ·  ·  ·  ·  by acidic treatment of aqueous silicate solutions  [3]
 C01B 33/155
·  ·  ·  ·  Preparation of hydroorganogels or organogels  [3]
 C01B 33/157
·  ·  ·  ·  After-treatment of gels  [3]
 C01B 33/158
·  ·  ·  ·  ·  Purification; Drying; Dehydrating  [3]
 C01B 33/159
·  ·  ·  ·  ·  Coating or hydrophobisation  [3]
 C01B 33/16
·  ·  ·  Preparation of silica xerogels  [3]
 C01B 33/18
·  ·  ·  Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof (preparation of aerogels by dehydrating gels C01B 33/158; treatment to enhance the pigmenting or filling properties C09C)  [3]
 C01B 33/187
·  ·  ·  ·  by acidic treatment of silicates  [3]
 C01B 33/193
·  ·  ·  ·  ·  of aqueous solutions of silicates  [3]
 C01B 33/20
·  Silicates (persilicates C01B 15/14)
 C01B 33/22
·  ·  Magnesium silicates
 C01B 33/24
·  ·  Alkaline-earth metal silicates
 C01B 33/26
·  ·  Aluminium-containing silicates
 C01B 33/28
·  ·  ·  Base exchange silicates, e.g. zeolites (regeneration B01J 49/00)
 C01B 33/30
·  ·  ·  Bleaching earth
 C01B 33/32
·  ·  Alkali metal silicates (C01B 33/26 takes precedence)  [3]
 C01B 35/00
Boron; Compounds thereof (monoborane, diborane, metal boranates or addition complexes thereof C01B 6/00; perborates C01B 15/12; binary compounds with nitrogen C01B 21/06; phosphides C01B 25/08; carbides C01B 31/36; alloys containing boron C22)  [2]
 C01B 35/02
·  Boron; Borides  [2]
 C01B 35/04
·  ·  Metal borides  [2]
 C01B 35/06
·  Boron halogen compounds  [2]
 C01B 35/08
·  Compounds containing boron and nitrogen, phosphorus, oxygen, sulphur, selenium or tellurium  [2]
 C01B 35/10
·  ·  Compounds containing boron and oxygen (C01B 35/06 takes precedence)  [2]
 C01B 35/12
·  ·  ·  Borates  [2]
 C01B 35/14
·  ·  Compounds containing boron and nitrogen, phosphorus, sulphur, selenium or tellurium  [2]
 C01B 35/16
·  Compounds containing direct bonding between two boron atoms, e.g. Cl2B—BCl2  [2]
 C01B 35/18
·  Compounds containing three or more boron atoms, e.g. Na B3H8, MgB10Br10 (borazoles C01B 35/14)  [2]