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. 09, 1990
Filed:
Feb. 27, 1989
Raymond F Dalton, Cheadle Hulme, GB;
Arthur Burgess, Oldham, GB;
Imperial Chemical Industries PLC, London, GB;
Abstract
An aqueous solution containing palladium is contacted with a solution of a heterocyclic ring compound having at least one ring substituent of the type --COX, which is, or contains, a hydrocarbyl group having at least 5 carbon atoms. The heterocyclic ring compound may be a pyridine mono-, di- or tri-carboxylic acid ester, for example the bis-isodecyl ester of pyridine- 3,5-dicarboxylic acid. Other heterocyclic ring compounds include those having a pyrimidine, pyrazine, pyridazine, 1,2,4-triazole or imidazole ring. Palladium is extracted into the water-immiscible solution while other metals, particularly platinum group metals, remain in the aqueous solution. The palladium can be stripped from the water-immiscible solution for example using a dilute aqueous solution of ammonia.