| 摘要 |
A method of de-waxing a hydrocarbon fuel oil distillate comprises fractionating the distillate to a plurality of fractions, the highest-boiling of which contains substantially the whole of the wax to be removed, cooling and agitating the highest boiling material in the presence of a wax crystal modifier, and filtering the wax, precipitated by the cooling, from a slurry which contains sufficient of the lowest-boiling fraction obtained from the fractionating to manifest a Brookfield viscosity (measured on the 100 scale with a No. 1 spindle at 30 r.p.m.) below 90 and a liquid phase viscosity below 40 centipoises. Preferably, the starting material is separated into three fractions. The wax crystal modifier may be selected from alpha- and beta-olefin polymers with a molecular weight from about 700 to about 2800 prepared from olefins containing from 15 to 21 carbon atoms, ethylene-vinyl acetate copolymers, polymeric vinyl esters of stearic and palmitic acids and the like. |
