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. 21, 1987
Filed:
Jul. 08, 1985
Joseph Pugach, Ridgewood, NJ (US);
The Halcon SD Group, Inc., Little Ferry, NJ (US);
Abstract
Heavy residues produced by noble metal catalyzed carbonylation reactions and containing Group VIII noble metals, particularly rhodium, are treated with reagents to precipitate solids containing substantially all of the noble metal contained in the residues. The solids may be further treated to concentrate the noble metals or they may be returned directly for reuse in the carbonylation reaction. Suitable reagents include aliphatic alcohols, carboxylic acids, and carboxylic acid esters. Preferred are branched-chain alcohols, especially tertiary alcohols; of the acids, acetic acid is particularly preferred; and of the esters, n-butyl acetate and ethylidene diacetate are preferred. Subsequent treatments with other solvents, e.g., alkanes, cycloalkanes, ethers, and aromatic compounds, may be used to further concentrate the rhodium content of the precipitated solids.