1,2-Dimethylbenzene 99%

Xylene refers to the aromatic hydrocarbon with the two hydrogen atoms on the benzene ring being substituted by two methyl groups. It has three isomers o-xylene (1, 2-Dimethylbenzene), m-xylene and p-xylene. The industrial products are the mixtures of the three isomers with 10% o-10%, 70% m-, and 20% p-. In the coking industry, it is one of crude benzene refined products.

Xylene is a kind of colorless flammable liquid; the melting point of o-, m-and p-xylene is-25.2 ℃,-47.9 ℃ and 13.3 ℃; the boiling points are respectively 144.4 ℃, 139.1 ℃ and 138.3 ℃ while the relative density is 0.8802, 0.8642 and 0.8611, respectively; It is not soluble in water but miscible with many kinds of organic solvents immiscibility. Upon catalytic oxidation, they respectively, generate phthalic anhydride, isophthalic acid and terephthalic acid.
Xylene is one kind of important raw materials of organic chemicals, naturally existing in coal tar and some kinds of petroleum. It can be obtained through the fractionation of the light oil part of the coal tar or catalytic reforming light gasoline. Industry mainly performs extracting using the C8 fraction in the naphtha reformates. It can be alternatively manufactured through the disproportionation reaction of toluene in the presence of catalyst and high temperature, high pressure. At present time, industry mainly applies the method of cryogenic crystallization, adsorption and formation of complexes or molecular sieves to separate them. O-xylene has a relatively high boiling point, being able to be separated using distillation. p-xylene also has a high melting point and can be purified through fractional crystallization purification. Mixed xylene without separation can be directly used as a solvent with being supplemented to the gasoline capable of improving the anti-explosive properties. They are components of aviation gasoline. O-xylene is mainly used for the preparation of phthalic anhydride, which is an important raw material for the manufacture of a variety of dyes and indicators (such as phenolphthalein). In addition, o-xylene can also be used for preparation of polyester resin, insect repellent, plasticizers and dyes. M-xylene, through nitration and reduction, can generate 4, 6-dimethyl-1, 3-phenylenediamine that is the intermediate for synthetic dyes. M-xylene can also be used as the raw materials for synthetic fragrances (such as xylene musk). P-xylene is mainly used in the manufacture of terephthalic acid, which is an important raw material for synthetic polyester fiber (polyester).