(19)

(11)

EP 0 530 275 A1

(12)

(43) Date of publication: 10.03.1993 Bulletin 1993/10 (21) Application number: 91910043.0 (22) Date of filing: 15.05.1991

(51) International Patent Classification (IPC):  B01J 35/ 10( . ) B01J 23/ 62( . ) B01J 23/ 89( . ) B01J 23/ 42( . ) B01J 23/ 656( . ) B01J 27/ 13( . ) (86) International application number: PCT/US1991/003379 (87) International publication number: WO 1991/017825 (28.11.1991 Gazette 1991/27)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI LU NL SE (30) Priority: 21.05.1990 US 19900525610 (71) Applicant: ENGELHARD CORPORATION Iselin, New Jersey 08830-0770 (US)	(72) Inventors: KHARE, Gyanesh, P. Bartlesville, OK 74006 (US) VON BALLMOOS, Roland Belle Meade, NJ 08502 (US) (74) Representative: Geering, Keith Edwin, et al  REDDIE & GROSE 16 Theobalds Road London WC1X 8PL London WC1X 8PL (GB)