Petrochemical
From Wikipedia, the free encyclopedia
Petrochemicals are chemical products made from raw materials of petroleum (hydrocarbon) origin. Although some of the chemical compounds which originate from petroleum may also be derived from other sources such as coal or natural gas, petroleum is a major source of many. This article is mainly intended to discuss organic compounds or materials which are not burned as fuel (see also Petroleum product).
The two main classes of petrochemical raw materials are olefins (including ethylene and propylene) and aromatics (including benzene and xylene isomers), both of which are produced in very large quantities. At oil refineries, olefins are produced mainly from hydrocarbons by chemical cracking such as steam cracking and by catalytic reforming. At oil refineries, aromatic hydrocarbons are mainly produced by catalytic reforming or similar processes. From these basic building blocks are made a very wide range of chemicals and other materials used in industry - monomers, solvents, detergents, etc. From the monomers, polymers or oligomers are produced for plastics, resins, fibers, elastomers, certain lubricants and gels.
World production of ethylene is around 110 million tonnes per annum, of propylene 65 million tonnes, and of aromatic raw materials 70 million tonnes. The largest petrochemical industries are to be found in the USA and Western Europe, though the major growth in new production capacity is in the Middle East and Asia. There is a substantial inter-regional trade in petrochemicals of all kinds.
The following is a partial list of the major commercial petrochemicals and their derivatives:
- ethylene
- polyethylenes
- ethylene oxide
- ethylene glycols
- glycol ethers
- ethoxylates
- vinyl acetate
- 1,2-dichloroethane
- ethylbenzene
- higher olefins
- detergent alcohols
- propylene
- butadiene
- benzene
- toluene
- mixed xylenes
