GB431683A - Improvements in the manufacture and production of aromatic hydrocarbons of low boiling point by hydrogenating coal tar fractions - Google Patents

Abstract

In obtaining low-boiling aromatic hydrocarbons from high-boiling hydrocarbon liquids consisting of or containing aromatic hydrocarbons and derived from mineral coal, such as coal tar fractions, or heavy benzene obtained by destructive hydrogenation of mineral coal, the liquids are first refined by a heat-treatment in presence of hydrogen under conditions to remove sulphur and oxygen compounds and to hydrogenate some of the double bonds without decomposition into lower molecular compounds. The treatment is effected at pressures above atmospheric, e.g. 20 atmospheres or more, and at temperatures of 100--450 DEG C. in presence of sulphurimmune catalysts. The liquid may be heated to about 200 DEG C., passed into a separator from which polymerized constituents are removed, and the remaining product be led with hydrogen over a heated catalyst. The material may be passed at 100--300 DEG C. under pressure over a hydrogenation catalyst such as the sulphides of metals of the 5th to 8th group, and then at 300--475 DEG C. over a catalyst consisting of oxides or sulphides of metals of the 5th and 6th group, at pressures up to 500 atmospheres. The refined product is led with hydrogen under 100--500 atmospheres pressure and at 500--700 DEG C. over catalysts such as compounds of the metals of 2nd to 8th groups. Specification 328,618, [Class 32], is referred to.