Isolation and regeneration of rhodium-containing catalysts from distillation residues of hydroformylation reactions

US4113754A · kind A · utility

Assignee

• BASF SE

Inventors

• Rudolf Kummer · Bischofswerda, DE
• Heinz-Walter Schneider · Ludwigshafen, DE
• Kurt Schwirten · Ludwigshafen, DE

Key dates

• Filing date: Mar 23, 1977
• Grant date: Sep 12, 1978
• Expiry date: Mar 23, 1997

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/584
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The isolation and regeneration of catalysts of type I or II EQU clRh(CO)(PR.sub.3).sub.2 I EQU hrh(CO)(PR.sub.3).sub.3 II, where the R's are identical or different hydrocarbon radicals, to give the catalysts in a pure form, is effected by regenerating aqueous rhodium salt solutions, as obtained on treating distillation residues of hydroformylation mixtures with oxygen-containing mineral acids and peroxides, by a method wherein the said aqueous rhodium salt solutions are treated with a cation exchanger, the latter is then separated from the solution, the absorbed rhodium ions are desorbed with hydrochloric acid, the hexachlororhodate solutions, containing hydrochloric acid, are reacted, in the presence of a water-soluble organic solvent and a tertiary phosphine PR.sub.3, with carbon monoxide, or with compounds which eliminate carbon monoxide, at from 0.degree. to 150.degree. C and from 1 to 5 bars, and the resulting complexes I or, if the process is carried out under hydrogenating conditions, the resulting complexes II, are separated off.