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:
Mar. 15, 1994
Filed:
Feb. 24, 1992
Herman L Gewanter, Waterford, CT (US);
Sandra I Graham, Mystic, CT (US);
Joseph M Rashan, Jr, Waterford, CT (US);
R Larry Reitz, Salem, CT (US);
Pfizer Inc., New York, NY (US);
Abstract
This invention relates to the use of certain keto and diketo acids, esters and salts that are derived from aldopentoses and aldohexoses, to maintain very high levels of iron in solution under oil well acidizing conditions. The compounds described herein chelate ferric iron at low temperatures and are activated by heat to reduce ferric iron to the more soluble ferrous species at high temperatures. Because of these properties and their extraordinarily high solubility in hydrochloric acid, such compounds are capable of maintaining considerably more iron in solution than competing materials.