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Coal tar is produced through thermal destruction of coal.Its composition varies with the process and type of coal used – lignite, bituminous or anthracite. [13]Coal tar is a mixture of approximately 10,000 chemicals, of which only about 50% have been identified.
Tar made from coal or petroleum is considered toxic and carcinogenic because of its high benzene content, [citation needed] though coal tar in low concentrations is used as a topical medicine for conditions such as psoriasis. [11] [12] Coal and petroleum tar has a pungent odor. Coal tar is listed at number 1999 in the United Nations list of ...
Pitch is a viscoelastic polymer which can be natural or manufactured, derived from petroleum, coal tar, [1] or plants. Pitch produced from petroleum may be called bitumen or asphalt , while plant-derived pitch, a resin , is known as rosin in its solid form.
The gasification of coal created a tar-like material, which traveled through wastewater under Bramlett Road to be discharged into the flood plain across the street.
Bitumen (asphalt or coal-tar pitch) is a material made up of organic liquids that are highly sticky, viscous, and waterproof. [1] Systems incorporating bituminous-based substrates are sometimes used to construct roofs, in the form of "roofing felt" or "roll roofing" products.
As the wastes produced by former manufactured gas plants were persistent in nature, they often (as of 2009) still contaminate the site of former manufactured gas plants: the waste causing the most concern today is primarily coal tar (mixed long-chain aromatic and aliphatic hydrocarbons, a byproduct of coal carbonization), while "blue billy" (a ...
Bituminous coal. Bituminous coal, or black coal, is a type of coal containing a tar-like substance called bitumen or asphalt. Its coloration can be black or sometimes dark brown; often there are well-defined bands of bright and dull material within the seams. It is typically hard but friable.
From the 1960s until the 1990s, significant amounts of naphthalene were produced from heavy petroleum fractions during refining, but present-day production is mainly from coal tar. [citation needed] Approximately 1.3 million tons are produced annually. [citation needed] Naphthalene is the most abundant single component of coal tar.