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:
Nov. 27, 1990
Filed:
Mar. 09, 1990
James M Paul, DeSoto, TX (US);
Peggy M Wilson, Dallas, TX (US);
Mobil Oil Corporation, Fairfax, VA (US);
Abstract
Surface layers of the earth contaminated with precipitates of alkaline earth metal sulfates including radium sulfate derived from subterranean waters brought to the surface of the earth, are decontaminated using an aqueous chemical composition including a polyaminopolycarboxylic acid such as ETDA or DTPA in combination with a synergist, preferably oxalate or monocarboxylic acid anion such as salicylate. The surface layers may be decontaminated in situ by applying the solvent to the earth to bring the precipitates into dissolved form after which the dissolved precipitates are leached into lower layers of the earth by percolation with water. Alternatively, the earth may be removed from its original site and decontaminated in a tank or lined pond after which the decontaminated earth may be returned to its approximate original site.