The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 05, 1978
Filed:
Oct. 28, 1976
Theodore H West, Sarnia, CA;
Exxon Research & Engineering Co., Linden, NJ (US);
Abstract
An improvement in a dilution chilling dewaxing process wherein waxy lubricating oil stocks are solvent dewaxed by contacting them with successive increments of cold dewaxing solvent at a plurality of points along the height of a vertical tower divided into a plurality of stages while agitating the oil-solvent mixture in each stage to provide substantially instantaneous mixing of the waxy oil and solvent thereby precipitating wax from the oil while avoiding the well known shock chilling effect. The improvement resides in using as the dewaxing solvent, a mixture selected from the group consisting of (a) methylene chloride and (b) acetone, methylethyl ketone, methanol and mixtures thereof, and wherein the methylene chloride comprises at least about 20 LV% of the dewaxing solvent. This invention results in substantial energy savings, requires less solvent per volume of waxy oil feed and gives significant improvements in the filtration rate of the dewaxed oil over conventional autorefrigerant and/or ketone dewaxing solvents.