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. 03, 1990
Filed:
Jul. 14, 1987
Thomas V Harris, Benicia, CA (US);
Cyrus A Irani, Hacienda Heights, CA (US);
Wayne R Pretzer, Wheaton, IL (US);
Chevron Research Company, San Francisco, CA (US);
Abstract
A method of increasing the viscosity of CO.sub.2 at least three-fold by adding (1) a viscosifying amount of a polymer having a Minimum Solubility Parameter of 6.85 or less and a plurality of electron donor atoms selected from the group consisting of O, N, and S, and (2) a sufficient amount of a cosolvent to form a one-phase solution, said cosolvent being capable of (a) dissolving at least 2% by weight of CO.sub.2 at 25.degree. C. and 900 psig, and (b) forming a one-phase mixture with the polymer when the mixture contains 10 weight percent cosolvent at ambient temperature and a pressure sufficient to maintain the cosolvent in the liquid phase. New compositions containing CO.sub.2, the defined polymer and cosolvent are also claimed as is a method for recovering oil from underground formations using a viscosified CO.sub.2.