| Material | Principal uses or sources of emission |
|---|---|
| Alumina | Catalyst support, catalyst (sulfur recovery) |
| Aluminium chloride | Catalyst (isomerization) |
| Amines, aliphatic (e.g., methylamine) and alkanolamines (e.g. monoethanolamine) | Hydrodesulfurization, acid gas adsorbents |
| Amines, aromatic (e.g., anisidines* and phenylenediamines*) | Catalytic cracking, residual processing, gasoline antioxidants |
| Ammonia | Atmospheric distillation, catalytic cracking, sulfur recovery, residual processing, lubricant oil processing, waste waters |
| Antimony trichloride | Inhibitor (isomerization) |
| Arsenic compounds* | Crude oil, gas scrubbing |
| Asbestos* | Pipe insulation, gaskets (formerly), valve seals |
| Bitumen (asphalt) fumes* | Solvent deasphalting, tanker loading, tank cleaning |
| tert-Butyl alcohol | Unleaded gasoline blending |
| Carbon monoxide | Catalyst regeneration (catalytic cracking), use of inert gases, boilers, flares |
| Chlorine | Rejuvenation of platinum catalyst, cooling water treatment |
| Chromium and chromium compounds* | Catalyst (catalytic reforming), welding |
| Clays (e.g., bentonite) | Catalyst supports, grease fillers |
| Cobalt and cobalt compounds (including cobalt carbonyl, cobalt molybdate, oxides) | Catalyst (catalytic reforming, hydrocracking, hydrotreating) |
| Coke | Coking units* |
| Copper and copper compounds (e.g. copper chloride, copper alloys) | Desulfurization, sweetening operations, catalyst (catalytic reforming) |
| Crude oil | Crude oil distillation and processing unit |
| 1,2-Dibromoethane (ethylene dibromide)* | Leaded gasoline blending |
| 1,2-Dichloroethane (ethylene dichloride)* | Leaded gasoline blending |
| Earth, diatomaceous (amorphous silica*) | Crude oil filtration, catalyst support, lubricant oil filtration |
| Fuels (e.g., gasoline, diesel oil, jet fuel, heating oil) | Fuel blending, storage, loading |
| Furfural | Oil and grease manufacture, desulfurization |
| Graphite | Grease filler |
| Hydrazine* | Boiler-water additive |
| Hydrocarbons, aliphatic (e.g., propane, n-hexane) | Most process units |
| Hydrocarbons, aromatic (e.g., benzene*, toluene) | Most process units, catalytic cracking and reforming, gasoline blending and loading, wax preparation unit |
| Hydrocarbons, chlorinated* | Rejuvenation of catalyst (catalytic reforming), solvents |
| Hydrogen chloride | Isomerization |
| Hydrogen fluoride (hydrofluoric acid) | Catalyst (alkylation) |
| Hydrogen sulfide and sulfur compounds (e.g., mercaptans, carbon disulfide) | Atmospheric distillation, catalytic cracking and reforming, hydrocracking, hydrotreating, sulfur recovery, residual processing, lubricant oil processing, waste waters |
| Iron and iron compounds* | Catalyst (hydrocracking), welding |
| Ketones (e.g., methyl ethyl ketone) | Lubricant oil solvent dewaxing, atmospheric distillation, residual processing |
| Lead, inorganic compounds (e.g., lead oxide)* | Desulfurization, removal, sweetening operations |
| Manganese compounds, organic | Unleaded gasoline blending |
| Methyl-tert-butyl ether | Unleaded gasoline blending |
| N-Methyl-2-pyrrolidone | Lubricant oil manufacture |
| Mineral oils (e.g., lubricating oils)* | Oil and grease units |
| Molybdenum and molybdenum compounds | Catalyst (catalytic reforming, hydrocracking, isomerization, hydrotreating) |
| Nickel and nickel compounds (e.g., nickel sulfides, nickel carbonyl, nickel oxide)* | Catalyst (isomerization, hydrotreating, hydrocracking, catalytic reforming), welding, cleaning residual fuel oils, combustion products |
| Nitrogen oxides | Flares, furnaces |
| Palladium | Catalyst (catalytic reforming, hydrocracking) |
| Phenol | Crude distillation, catalytic cracking, residual processing, waste waters, desulfurization, lubricant oil, solvent dewaxing |
| Phosgene | Catalyst rejuvenation by chlorination (catalytic reforming) |
| Pitch (petroleum) | Bitumen department, loading operations |
| Phosphoric acid | Catalyst (polymerization) |
| Platinum | Catalyst (catalytic reforming, isomerization, hydrotreating) |
| Polynuclear aromatic compounds* | Atmospheric distillation, catalytic cracking, residual fuel oil, lubricant oil processing, bitumen processing and loading, coking, waste-water treatment |
| Refined petroleum solvents (e.g., petroleum ether, rubber solvent, varnish makers' and painters' naphtha, Stoddard solvent) | Petroleum solvent manufacturing |
| Rhenium | Catalyst (catalytic reforming) |
| Silica, crystalline* | Abrasive blasting, demolition and rebuilding, cracking (catalyst) |
| Sodium hydroxide | Caustic wash of acid catalysts or acid-treated streams, sweetening operations |
| Sulfur | Sulfur recovery |
| Sulfur dioxide | Sulfur recovery, furnaces, flares |
| Sulfuric acid | Catalyst (alkylation, polymerization), acid treating of lubricant oils |
| Tetraethyllead and tetramethyllead* | Gasoline blending operations, gasoline storage tank cleaning |
| Tungsten sulfide | Catalyst (hydrocracking) |
| Vanadium compounds (e.g., vanadium pentoxide) | Residual fuel oils, cleaning of combustion deposits, flue cleaning |
*Compounds marked with an asterisk have been evaluated by the IARC (see IARC, 1987; see also Table 1 of ‘General Remarks’, p. 32)
From: OCCUPATIONAL EXPOSURES IN PETROLEUM REFINING
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