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Coal tar causes increased sensitivity to sunlight, [55] so skin treated with topical coal tar preparations should be protected from sunlight. The residue from the distillation of high-temperature coal tar, primarily a complex mixture of three or more membered condensed ring aromatic hydrocarbons , was listed on 13 January 2010 as a substance of ...
One can produce a tar-like substance from corn stalks by heating them in a microwave oven. This process is known as pyrolysis. Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. [1]
Natural bitumen pitch, from the tar pit above the McKittrick Oil Field, Kern County, California. 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 ...
In the earliest days of MGP operations, coal tar was considered a waste and often disposed into the environment in and around the plant locations. While uses for coal tar developed by the late-19th century, the market for tar varied and plants that could not sell tar at a given time could store tar for future use, attempt to burn it as boiler ...
Styrene is named after storax balsam (often commercially sold as styrax), the resin of Liquidambar trees of the Altingiaceae plant family. Styrene occurs naturally in small quantities in some plants and foods ( cinnamon , coffee beans , balsam trees and peanuts ) [ 7 ] and is also found in coal tar .
The term creosote has a broad range of definitions depending on the origin of the coal tar oil and end-use of the material. With respect to wood preservatives, the United States Environmental Protection Agency (EPA) considers the term creosote to mean a pesticide for use as a wood preservative meeting the American Wood Protection Association (AWPA) Standards P1/P13 and P2. [6]
The use of coal as fuel causes health problems and deaths. [123] The mining and processing of coal causes air and water pollution. [124] Coal-powered plants emit nitrogen oxides, sulfur dioxide, particulate pollution, and heavy metals, which adversely affect human health. [124] Coal bed methane extraction is important to avoid mining accidents.
Juglone is an example of such a molecule inhibiting the growth of other plant species around walnut trees. [ citation needed ] The aquatic vascular plant Myriophyllum spicatum produces ellagic , gallic and pyrogallic acids and (+)- catechin , allelopathic phenolic compounds inhibiting the growth of blue-green alga Microcystis aeruginosa .