Biphenyl is an important organic raw material widely used in medicine, pesticides, dyes, liquid crystal materials and other fields. It can be used to synthesize plasticizers, preservatives, and can also be used in the manufacture of fuels, engineering plastics, and high-energy fuels. Biphenyl is present in coal tar, crude oil and natural gas. The preparation method of biphenyl includes a chemical synthesis method of producing biphenyl by pyrolysis of benzene, and a separation and extraction method of biphenyl by various coal tar fractions. The mass fraction of biphenyl in coal tar is 0.20%-0.40%. At present, coal tar extraction method and chemical synthesis method coexist.
Nature and stability editing
1. Flammable, be careful not to be near fire.
It is heat stable, chemically similar to benzene, and can undergo halogenation, nitration, sulfonation, hydrogenation and the like. For example, it reacts with bromine to form a bromine derivative. Nitrobiphenyl is formed during nitrification. Sulfonation with sulfuric acid in nitrobenzene produces biphenyl-4-sulfonic acid and biphenyl-4,4'-disulfonic acid. It reacts with ozone in chloroform to form an explosive tetraodor oxide. The alkylation reaction produces 4-alkylbiphenyl and 4,4'-dialkylbiphenyl. It reacts with acetyl chloride in the presence of aluminum trichloride to form 4-acetylbiphenyl and 4,4'-diacetylbiphenyl. The carbon disulfide is used as a solvent, and reacted with oxalyl chloride to be hydrolyzed to form a biphenyl-4-carboxylic acid. A chloromethylation reaction occurs with formaldehyde and hydrochloric acid in the presence of zinc chloride.
2. This product has a stimulating effect, damage to the heart muscle, liver and kidney, rat oral LD50: 3280mg / kg (25% olive oil solution), 240mg / kg for rabbits.
3. It is found in flue-cured tobacco leaves, oriental tobacco leaves, and flue gas.
White or slightly yellow scaly crystal, with a unique fragrance.
UN 3077 9/PG 3
Cool,dry and hermetic place
Engineering plastics polysulfone raw materials, the system of trichlorobiphenyl, pentachlorobenzene, as heat carrier, preservatives, dyes, etc.