(19)

(11)

EP 0 909 368 A1

(12)

(43) Date of publication: 21.04.1999 Bulletin 1999/16 (21) Application number: 97927064.0 (22) Date of filing: 23.05.1997

(51) International Patent Classification (IPC):  F17C 1/ 00( . ) F17C 1/ 10( . ) F17C 1/ 04( . ) (86) International application number: PCT/EP1997/002773 (87) International publication number: WO 1997/045672 (04.12.1997 Gazette 1997/52)

(84) Designated Contracting States: AT BE CH DE DK ES FI GB GR IE IT LI LU NL PT SE (30) Priority: 24.05.1996 FR 19960006490 (71) Applicant: SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ B.V. 2596 HR Den Haag (NL)	(72) Inventor: MAYRAS, Patrick, Maurice, Louis F-92523 Neuilly sur Seine (FR)