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:
Apr. 17, 1990
Filed:
Nov. 10, 1988
Lillian A Rankel, Princeton, NJ (US);
Darrell D Whitehurst, Titusville, NJ (US);
Mobil Oil Corporation, New York, NY (US);
Abstract
This invention provides a method for extending the catalytic dewaxing cycle time of a refined waxy lube stock. The method, in its broadest aspect, requires the additional refining step of thermally treating the refined waxy stock or precursor thereof for about 0.1 to about 2.0 hours at elevated temperature and at a pressure of 0 to 3000 psig (pounds per square inch gauge), and recovering an upgraded waxy stock having a reduced content of trace compounds that contain metals, nitrogen, sulfur and oxygen. In a specific embodiment of this invention, a vacuum residuum is thermally treated at a temperature of about 700.degree. F. to 950.degree. F. prior to solvent deasphalting and solvent extraction, and the waxy bright stock so formed is catalytically dewaxed with extended cycle time.