GB505141A - A process for refining hydrocarbon oils - Google Patents

Abstract

505,141. Purifying oils and waxes. ELKINGTON, H. D. (Naamlooze Vennootschap de Bataafsche Petroleum Maatschappij) June 10, 1938, No. 17326. [Class 91] In the refining of mineral oils by treating with a strong acid, the sludge is separated in the presence of a low-molecular hydrocarbon at a temperature above the critical temperature thereof. The low-molecular hydrocarbon may be added before, during, or after the addition of acid. Examples are, methane, ethane, propane, n-or iso-pentane or -butane, propylene, ethylene, or natural gas. The oil may be pre-diluted with mutual solvent for the oil and low-molecular hydrocarbon, whereby high pressures are avoided. Examples are, ethane, propane, butanes, heptanes, gasoline, naphtha, or chlorinated hydrocarbons such as propyl chloride. Strong acids specified are, sulphuric, phosphoric or a mixture of sulphuric and acetic acids. Crude wax-containing mineral and tar oils, or distillates especially lubricating and transformer oils are treated. In an example, a residual oil is freed from asphalt by adding propane, and the resulting solution is saturated with methane at 300 1b. pressure and treated with concentrated or fuming sulphuric acid at 20‹ C. After agitation, the sludge readily settles, and the oil is freed from ethane, and propane, and finally neutralized with caustic soda, isopentane being added to avoid emulsions. Waxes may also be purified at a temperature above the melting point.