GB394414A - Method of refining oil-wax mixtures - Google Patents

Abstract

Oil-wax mixtures containing 5 per cent or more of paraffin wax are refined, prior to separation by known processes into wax and oils, by treating the melted mixture at 180 DEG C. or lower with anhydrous chloride of aluminium iron, zinc, tin, antimony, or chromium, or mixtures thereof, and separating the sludge as by settling, then filtering through an absorbent e.g. fuller's earth or bauxite or by settling, centrifuging, and then filtering. The pressure is preferably slightly below atmospheric but may be atmospheric or slightly above. The sludge may be treated to recover the chloride or to make asphaltic bitumen. Mixtures specified for treatment are reduced or topped crude oil, wax-containing distillates, scale wax and sweated scale wax. Specified processes of separating the wax from the oil are distillation, sweating, centrifuging and pressing with or without blending with naphtha and with or without the use of a filter aid. In examples: (1) Crude oil topped to 300 DEG C. is agitated for 10 min. at 135 DEG C., first with 1 per cent and then twice with 2 per cent of aluminium chloride; the sludge is allowed to settle out, and the oil is separated, filtered through fuller's earth and distilled under reduced pressure to obtain gas oil, a distillate from which wax scale and lubricating oil are obtained by pressing, and a residue from which viscous oil and crude petroleum are obtained by cold settling with naphtha. (2) Sweated scale wax M.P. 135.7 DEG F. is violently agitated at 100 DEG C. with 0.25 per cent of aluminium chloride for 75 min., and allowed to settle; the wax is separated and filtered through fuller's earth.