|  | 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 Section C covers: pure chemistry, which covers inorganic compounds, organic compounds, macromolecular compounds, and their methods of preparation; applied chemistry, which covers compositions containing the above compounds, such as: glass, ceramics, fertilisers, plastics compositions, paints, products of the petroleum industry. It also covers certain compositions on account of their having particular properties rendering them suitable for certain purposes, as in the case of explosives, dyestuffs, adhesives, lubricants, and detergents; certain marginal industries, such as the manufacture of coke and of solid or gaseous fuels, the production and refining of oils, fats and waxes, the fermentation industry (e.g., brewing and wine-making), the sugar industry; certain operations or treatments, which are either purely mechanical, e.g., the mechanical treatment of leather and skins, or partly mechanical, e.g., the treatment of water or the prevention of corrosion in general; metallurgy, ferrous or non-ferrous alloys. In the case of operations, treatments, products or articles having both a chemical and a non-chemical part or aspect, the general rule is that the chemical part or aspect is covered by section C. In some of these cases, the chemical part or aspect brings with it a non-chemical one, even though purely mechanical, because this latter aspect either is essential to the operation or treatment or constitutes an important element thereof. It has seemed, in fact, more logical not to dissociate the different parts or aspects of a coherent whole. This is the case for applied chemistry and for the industries, operations and treatments mentioned in Notes (1)(c), (d) and (e). For example, furnaces peculiar to the manufacture of glass are covered by class Fulltext... Hierarchy... Expanded...C03 and not by class Fulltext... Hierarchy... Expanded...F27. There are, however, some exceptions in which the mechanical (or non-chemical) aspect carries with it the chemical aspect, for example: Certain extractive processes, in subclass Fulltext... Hierarchy... Expanded...A61K; The chemical purification of air, in subclass Fulltext... Hierarchy... Expanded...A61L; Chemical methods of fire-fighting, in subclass Fulltext... Hierarchy... Expanded...A62D; Chemical processes and apparatus, in class Fulltext... Hierarchy... Expanded...B01; Impregnation of wood, in subclass Fulltext... Hierarchy... Expanded...B27K; Chemical methods of analysis or testing, in subclass Fulltext... Hierarchy... Expanded...G01N; Photographic materials and processes, in class Fulltext... Hierarchy... Expanded...G03, and, generally, the chemical treatment of textiles and the production of cellulose or paper, in section D. In still other cases, the pure chemical aspect is covered by section C and the applied chemical aspect by another section, such as A, B or F, e.g., the use of a substance or composition for: treatment of plants or animals, covered by subclass Fulltext... Hierarchy... Expanded...A01N; foodstuffs, covered by class Fulltext... Hierarchy... Expanded...A23; ammunition or explosives, covered by class Fulltext... Hierarchy... Expanded...F42. When the chemical and mechanical aspects are so closely interlocked that a neat and simple division is not possible, or when certain mechanical processes follow as a natural or logical continuation of a chemical treatment, section C may cover, in addition to the chemical aspect, a part only of the mechanical aspect, e.g., after-treatment of artificial stone, covered by class Fulltext... Hierarchy... Expanded...C04. In this latter case, a note or a reference is usually given to make the position clear, even if sometimes the division is rather arbitrary.

METALLURGY

|  | C22 |
METALLURGY (of iron Fulltext... Hierarchy... Expanded...C21); FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS (general methods or devices for heat treatment of ferrous or non-ferrous metals or alloys Fulltext... Hierarchy... Expanded...C21D; production of metals by electrolysis or electrophoresis Fulltext... Hierarchy... Expanded...C25)

|  | C22B |
PRODUCTION OR REFINING OF METALS (making metallic powder or suspensions thereof Fulltext... Hierarchy... Expanded...B22F 9/00; electrolytic Fulltext... Hierarchy... Expanded...C25); PRETREATMENT OF RAW MATERIALS

|  | C22B |
Note(s) In this subclass, groups for obtaining metals include obtaining the metals by non-metallurgical processes, and obtaining metal compounds by metallurgical processes. Thus, for example, group Fulltext... Hierarchy... Expanded...C22B 11/00 covers the production of silver by reduction of ammoniacal silver oxide in solution, and group Fulltext... Hierarchy... Expanded...C22B 17/00 covers the production of cadmium oxide by a metallurgical process. Furthermore, although compounds of arsenic and antimony are classified in Fulltext... Hierarchy... Expanded...C01G, production of the elements themselves is covered by Fulltext... Hierarchy... Expanded...C22B, as well as the production of their compounds by metallurgical processes. Processes using enzymes or micro-organisms in order to: liberate, separate or purify a pre-existing compound or composition, or to treat textiles or clean solid surfaces of materials are further classified in subclass Fulltext... Hierarchy... Expanded...C12S. [5]

|  | C22B |
Subclass index
PRETREATMENT OF RAW MATERIALS | 1/00, 4/00, 7/00
PROCESSES FOR OBTAINING METALS | 3/00, 4/00, 5/00
REFINING OR REMELTING METALS | 9/00
OBTAINING SPECIFIC METALS | 11/00 - 61/00

P:220 |  | C22B 1/00 |
Preliminary treatment of ores or scrap (furnaces, sintering apparatus Fulltext... Hierarchy... Expanded...F27B)

|  | C22B 1/02 |
· | Roasting processes (Fulltext... Hierarchy... Expanded...C22B 1/16 takes precedence)

|  | C22B 1/04 |
· · | Blast roasting

|  | C22B 1/06 |
· · | Sulfating roasting

|  | C22B 1/08 |
· · | Chloridising roasting

|  | C22B 1/10 |
· · | in fluidised form

|  | C22B 1/11 |
· | Removing sulfur, phosphorus or arsenic, other than by roasting [2]

|  | C22B 1/14 |
· | Agglomerating; Briquetting; Binding; Granulating

|  | C22B 1/16 |
· · | Sintering; Agglomerating

|  | C22B 1/18 |
· · · | in sinter pots

|  | C22B 1/20 |
· · · | in sintering machines with movable grates

|  | C22B 1/212 |
· · · | in tunnel furnaces [2]

|  | C22B 1/214 |
· · · | in shaft furnaces [2]

|  | C22B 1/216 |
· · · | in rotary furnaces [2]

|  | C22B 1/22 |
· · · | in other sintering apparatus

|  | C22B 1/24 |
· · | Binding; Briquetting

|  | C22B 1/242 |
· · · | with binders [2]

|  | C22B 1/243 |
· · · · | inorganic [2]

|  | C22B 1/244 |
· · · · | organic [2]

|  | C22B 1/245 |
· · · · · | with carbonaceous material for the production of coked agglomerates [2]

|  | C22B 1/248 |
· · · | of metal scrap or alloys [2]

|  | C22B 1/26 |
· | Cooling of roasted, sintered, or agglomerated ores

P:210 |  | C22B 3/00 |
Extraction of metal compounds from ores or concentrates by wet processes [5]

|  | C22B 3/00 |
Note(s) When classifying in this group, the nature of any metal which is considered to represent information of interest for search may also be classified in the main groups only of Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C22B 11/00-C22B 25/00, in group Fulltext... Hierarchy... Expanded...C22B 19/34 or in any of groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C22B 26/00-C22B 61/00. This can, for example, be the case when it is considered of interest to enable searching for extraction of specific metals or their compounds. Such non-obligatory classification should be given as "additional information". [8]

|  | C22B 3/02 |
· | Apparatus therefor

|  | C22B 3/04 |
· | by leaching (Fulltext... Hierarchy... Expanded...C22B 3/18 takes precedence) [5]

|  | C22B 3/06 |
· · | in inorganic acid solutions [5]

|  | C22B 3/08 |
· · · | Sulfuric acid [5]

|  | C22B 3/10 |
· · · | Hydrochloric acid [5]

|  | C22B 3/12 |
· · | in inorganic alkaline solutions [5]

|  | C22B 3/14 |
· · · | containing ammonia or ammonium salts [5]

|  | C22B 3/16 |
· · | in organic solutions [5]

|  | C22B 3/18 |
· | with the aid of micro-organisms or enzymes, e.g. bacteria or algae [5]

|  | C22B 3/20 |
· | Treatment or purification of solutions, e.g. obtained by leaching (Fulltext... Hierarchy... Expanded...C22B 3/18 takes precedence) [5]

|  | C22B 3/22 |
· · | by physical processes, e.g. by filtration, by magnetic means (Fulltext... Hierarchy... Expanded...C22B 3/26 takes precedence) [5]

|  | C22B 3/24 |
· · · | by adsorption on solid substances, e.g. by extraction with solid resins [5]

|  | C22B 3/26 |
· · | by liquid-liquid extraction using organic compounds [5]

|  | C22B 3/28 - C22B 3/40 |
Note(s) In groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C22B 3/28-C22B 3/40: in the absence of an indication to the contrary, compounds are classified in the last appropriate place; when two or more compounds are used successively, each compound is classified as such; mixtures containing two or more compounds covered individually by the same one of groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C22B 3/28-C22B 3/38, are classified only in that group. [5]

|  | C22B 3/28 |
· · · | Amines [5]

|  | C22B 3/30 |
· · · | Oximes [5]

|  | C22B 3/32 |
· · · | Carboxylic acids [5]

|  | C22B 3/34 |
· · · | containing sulfur [5]

|  | C22B 3/36 |
· · · | Heterocyclic compounds (Fulltext... Hierarchy... Expanded...C22B 3/34 takes precedence) [5]

|  | C22B 3/38 |
· · · | containing phosphorus [5]

|  | C22B 3/40 |
· · · | Mixtures [5]

|  | C22B 3/42 |
· · | by ion-exchange extraction [5]

|  | C22B 3/44 |
· · | by chemical processes (Fulltext... Hierarchy... Expanded...C22B 3/26, Fulltext... Hierarchy... Expanded...C22B 3/42 take precedence) [5]

|  | C22B 3/46 |
· · · | by substitution, e.g. by cementation [5]

P:200 |  | C22B 4/00 |
Electrothermal treatment of ores or metallurgical products for obtaining metals or alloys (general methods of refining or remelting metals Fulltext... Hierarchy... Expanded...C22B 9/00; obtaining iron or steel Fulltext... Hierarchy... Expanded...C21B, Fulltext... Hierarchy... Expanded...C21C) [2]

|  | C22B 4/02 |
· | Light metals [2]

|  | C22B 4/04 |
· | Heavy metals [2]

|  | C22B 4/06 |
· | Alloys [2]

|  | C22B 4/08 |
· | Apparatus (electric heating elements Fulltext... Hierarchy... Expanded...H05B) [2]

P:230 |  | C22B 5/00 |
General processes of reducing to metals

|  | C22B 5/02 |
· | Dry processes

|  | C22B 5/04 |
· · | by aluminium, other metals, or silicon

|  | C22B 5/06 |
· · | by carbides or the like

|  | C22B 5/08 |
· · | by sulfides; Roasting reaction processes

|  | C22B 5/10 |
· · | by solid carbonaceous reducing agents

|  | C22B 5/12 |
· · | by gases

|  | C22B 5/14 |
· · · | fluidised material

|  | C22B 5/16 |
· · | with volatilisation or condensation of the metal being produced

|  | C22B 5/18 |
· · | Reducing step-by-step

|  | C22B 5/20 |
· · | from metal carbonyls

P:190 |  | C22B 7/00 |
Working-up raw materials other than ores, e.g. scrap, to produce non-ferrous metals or compounds thereof

|  | C22B 7/02 |
· | Working-up flue dust

|  | C22B 7/04 |
· | Working-up slag

P:240 |  | C22B 9/00 |
General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals

|  | C22B 9/02 |
· | Refining by liquating, filtering, centrifuging, distilling or supersonic wave action

|  | C22B 9/04 |
· | Refining by applying a vacuum [3]

|  | C22B 9/05 |
· | Refining by treating with gases, e.g. gas flushing [3]

|  | C22B 9/10 |
· | with refining or fluxing agents; Use of materials therefor (Fulltext... Hierarchy... Expanded...C22B 9/18 takes precedence) [3]

|  | C22B 9/14 |
· | Refining in the solid state

|  | C22B 9/16 |
· | Remelting metals (liquating Fulltext... Hierarchy... Expanded...C22B 9/02) [3]

|  | C22B 9/18 |
· · | Electroslag remelting [3]

|  | C22B 9/187 |
· · · | Apparatus therefor, e.g. furnaces [5]

|  | C22B 9/193 |
· · · · | Moulds, bottom plates or starter plates [5]

|  | C22B 9/20 |
· · | Arc remelting [3]

|  | C22B 9/21 |
· · · | Apparatus therefor [5]

|  | C22B 9/22 |
· · | with heating by wave energy or particle radiation [3]

P:170 |  | C22B 11/00 |
Obtaining noble metals

|  | C22B 11/02 |
· | by dry processes

|  | C22B 11/06 |
· | Chloridising

|  | C22B 11/08 |
· | by cyaniding

|  | C22B 11/10 |
· | by amalgamating

|  | C22B 11/12 |
· · | Apparatus therefor

P:160 |  | C22B 13/00 |
Obtaining lead

|  | C22B 13/02 |
· | by dry processes

|  | C22B 13/06 |
· | Refining

|  | C22B 13/08 |
· · | Separating metals from lead by precipitating, e.g. by Parkes process

|  | C22B 13/10 |
· · | Separating metals from lead by crystallising, e.g. by Pattison process

P:150 |  | C22B 15/00 |
Obtaining copper

|  | C22B 15/02 |
· | in blast furnaces

|  | C22B 15/04 |
· | in reverberatory furnaces

|  | C22B 15/06 |
· | in converters

|  | C22B 15/14 |
· | Refining

P:140 |  | C22B 17/00 |
Obtaining cadmium

|  | C22B 17/02 |
· | by dry processes

|  | C22B 17/06 |
· | Refining

P:130 |  | C22B 19/00 |
Obtaining zinc or zinc oxide

|  | C22B 19/02 |
· | Preliminary treatment of ores; Preliminary refining of zinc oxide

|  | C22B 19/04 |
· | Obtaining zinc by distilling

|  | C22B 19/06 |
· · | in muffle furnaces

|  | C22B 19/08 |
· · | in blast furnaces

|  | C22B 19/10 |
· · | in reverberatory furnaces

|  | C22B 19/12 |
· · | in crucible furnaces

|  | C22B 19/14 |
· · | in vertical retorts

|  | C22B 19/16 |
· · | Distilling vessels

|  | C22B 19/18 |
· · · | Condensers; Receiving vessels

|  | C22B 19/20 |
· | Obtaining zinc otherwise than by distilling

|  | C22B 19/28 |
· | from muffle furnace residues

|  | C22B 19/30 |
· | from metallic residues or scraps

|  | C22B 19/32 |
· | Refining zinc

|  | C22B 19/34 |
· | Obtaining zinc oxide (purifying zinc oxide Fulltext... Hierarchy... Expanded...C01G 9/02)

|  | C22B 19/36 |
· · | in blast or reverberatory furnaces

|  | C22B 19/38 |
· · | in rotary furnaces

P:120 |  | C22B 21/00 |
Obtaining aluminium

|  | C22B 21/02 |
· | with reducing

|  | C22B 21/04 |
· | with alkali metals

|  | C22B 21/06 |
· | Refining

P:110 |  | C22B 23/00 |
Obtaining nickel or cobalt

|  | C22B 23/02 |
· | by dry processes

|  | C22B 23/06 |
· | Refining

P:100 |  | C22B 25/00 |
Obtaining tin

|  | C22B 25/02 |
· | by dry processes

|  | C22B 25/06 |
· | from scrap, especially tin scrap (by electrolytic process Fulltext... Hierarchy... Expanded...C25C 1/14)

|  | C22B 25/08 |
· | Refining

P:90 |  | C22B 26/00 |
Obtaining alkali, alkaline earth metals or magnesium [2]

|  | C22B 26/10 |
· | Obtaining alkali metals [2]

|  | C22B 26/12 |
· · | Obtaining lithium [2]

|  | C22B 26/20 |
· | Obtaining alkaline earth metals or magnesium [2]

|  | C22B 26/22 |
· · | Obtaining magnesium [2]

P:80 |  | C22B 30/00 |
Obtaining antimony, arsenic or bismuth [2]

|  | C22B 30/02 |
· | Obtaining antimony [2]

|  | C22B 30/04 |
· | Obtaining arsenic [2]

|  | C22B 30/06 |
· | Obtaining bismuth [2]

P:70 |  | C22B 34/00 |
Obtaining refractory metals [2]

|  | C22B 34/10 |
· | Obtaining titanium, zirconium or hafnium [2]

|  | C22B 34/12 |
· · | Obtaining titanium [2]

|  | C22B 34/14 |
· · | Obtaining zirconium or hafnium [2]

|  | C22B 34/20 |
· | Obtaining niobium, tantalum or vanadium [2]

|  | C22B 34/22 |
· · | Obtaining vanadium [2]

|  | C22B 34/24 |
· · | Obtaining niobium or tantalum [2]

|  | C22B 34/30 |
· | Obtaining chromium, molybdenum or tungsten [2]

|  | C22B 34/32 |
· · | Obtaining chromium [2]

|  | C22B 34/34 |
· · | Obtaining molybdenum [2]

|  | C22B 34/36 |
· · | Obtaining tungsten [2]

P:60 |  | C22B 35/00 |
Obtaining beryllium

P:50 |  | C22B 41/00 |
Obtaining germanium

P:40 |  | C22B 43/00 |
Obtaining mercury

P:30 |  | C22B 47/00 |
Obtaining manganese

P:20 |  | C22B 58/00 |
Obtaining gallium or indium [2]

P:10 |  | C22B 59/00 |
Obtaining rare earth metals

P:0 |  | C22B 60/00 |
Obtaining metals of atomic number 87 or higher, i.e. radioactive metals [2]

|  | C22B 60/02 |
· | Obtaining thorium, uranium or other actinides [2]

|  | C22B 60/04 |
· · | Obtaining plutonium [2]

P:180 |  | C22B 61/00 |
Obtaining metals not elsewhere provided for in this subclass (iron Fulltext... Hierarchy... Expanded...C21) [2]