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:
Oct. 17, 1989
Filed:
Aug. 12, 1988
Lucie Y LaFreniere, Brights Cove, CA;
Exxon Research and Engineering Company, Florham Park, NJ (US);
Abstract
A method is disclosed for reducing the cloud point of materials comprising the steps of chilling the waxy oil so as to achieve submicron crystallization followed by ultrafiltration thereby effecting separation of a permeate of reduced cloud point from a retentate. Chilling to produce submicron crystallization is to a temperature about 3.degree. C. or less above the cloud point of the material, preferably from 0.5.degree. to 2.degree. C. above the cloud point of the material, most preferably between 1.degree. to 2.degree. C. above the cloud point of the material. In general any mixture, solution or melt containing components which crystallize at different temperatures can be separated by this procedure. The method is especially useful for reducing the cloud point of waxy hydrocarbon oils. The ultrafiltration membrane used will be one which is inert in and non-reactive with the components of the solution, mixture or melt, will not melt at the temperatures employed, which possesses an effective pore size smaller than the submicron crystals formed upon chilling and which does not have a strong chemical affinity for the crystallized component of the feed mixture, solution or melt.