(19)

(11)

EP 0 969 931 A1

(12)

(43) Date of publication: 12.01.2000 Bulletin 2000/02 (21) Application number: 98905416.8 (22) Date of filing: 06.02.1998

(51) International Patent Classification (IPC)7: B01J 37/20, B01J 37/12 (86) International application number: PCT/EP9800/722 (87) International publication number: WO 9834/728 (13.08.1998 Gazette 1998/32)

(84) Designated Contracting States: BE DE DK FR GB IT LU NL (30) Priority: 07.02.1997 US 797021 (71) Applicant: SHELL INTERNATIONALE RESEARCHMAATSCHAPPIJ B.V. 2596 HR Den Haag (NL)	(72) Inventors: ADAMS, Charles, Terrell Houston, TX 77079 (US) CHEN, Andrew, An-Ju Houston, TX 77077 (US)