(19)

(11)

EP 0 649 343 A1

(12)

(43) Date of publication: 26.04.1995 Bulletin 1995/17 (21) Application number: 93913253.0 (22) Date of filing: 28.05.1993

(51) International Patent Classification (IPC):  B01D 53/ 86( . ) B01J 35/ 04( . ) C01B 21/ 26( . ) C01C 3/ 02( . ) B01J 19/ 32( . ) B01J 35/ 06( . ) C01B 21/ 28( . ) (86) International application number: PCT/GB1993/001147 (87) International publication number: WO 1993/024229 (09.12.1993 Gazette 1993/29)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 01.06.1992 GB 19920011534 (71) Applicant: PGP INDUSTRIES, INC. Santa Fe Springs, CA 90670 (US)	(72) Inventors: HEYWOOD, Alan, Edward 209 Hughenden Road Hertfordshire AL4 9QP (GB) SCORGIE, Alan PGP Industries, Inc. Santa Fe Springs, CA 90670 (US) CRANSTON, Joseph, James Glen Mills, PA 19342 (US) (74) Representative: Cummings, Sean Patrick, et al  David Keltie Associates Audrey House Ely Place London EC1N 6SN London EC1N 6SN (GB)