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. 10, 2001
Filed:
Feb. 10, 1998
Chi Hung Cheng, Baton Rouge, LA (US);
John F. Balhoff, Baton Rouge, LA (US);
Ronny W. Lin, Baton Rouge, LA (US);
Albemarle Corporation, Richmond, VA (US);
Abstract
It has been found possible to separate catalytically-active aminophosphonium catalysts from mixtures composed predominately of aminophosphonium catalyst residue(s) and heavy ends from a halogen exchange reaction conducted in an aprotic solvent/diluent by extracting such mixtures with a neutral or acidic aqueous extraction solvent medium. Various ways of isolating from the halogen exchange reaction product mixture a mixture composed predominately of aminophosphonium catalyst residue(s) and heavy ends are described. Halogen exchange processes in which the catalytically-active aminophosphonium catalysts are separated for reuse are also described. Since aminophosphonium catalysts are expensive, the present process technology fulfills a need which has existed for an effective way of recovering such catalysts in catalytically active form enabling reuse of such materials, especially as halogen exchange catalysts.