METHOD OF RECOVERING N-HEXANE FROM HEXANE-CONTAINING GASOLINE FRACTIONS Russian patent published in 1999 - IPC

FIELD: chemical technology. SUBSTANCE: present invention describes method of recovering n-hexane from hexane-containing gasoline fraction comprising, in addition to n-hexane, identically boiling hydrocarbons such as 2,2-dimethylbutane, 2,3- dimethylbutane, 2-methyl-pentane, 3-methylpentane, methylcyclopentane and other C₅-C₆ paraffinic and cycloparaffinic hydrocarbons. Present invention also describes method of recovering n-hexane (from stock) having purity higher than 99 wt %. All properties of n- hexane meet specifications for n-heptane of pure type prepared by rectification on two columns with separating agent which is mixture of benzene and n-heptane. In first column, overhead fraction of light hydrocarbons is isolated at atmospheric pressure; in second column, n- haxane is isolated at pressure of 800-7000 mm Hg from bottom product of first column. n-hexane is further purified from benzene by absorption on zeolites or by treatment with oleum. EFFECT: expanded stock base, simplified technology of the process, reduced cost price and increase yield of the desired product. 13 ex