(19)

(11)

EP 0 611 325 A1

(12)

(43) Date of publication: 24.08.1994 Bulletin 1994/34 (21) Application number: 92921613.0 (22) Date of filing: 07.10.1992

(51) International Patent Classification (IPC):  B01D 50/ 00( . ) G01N 1/ 22( . ) B07B 9/ 00( . ) G01N 1/ 24( . ) (86) International application number: PCT/US1992/008532 (87) International publication number: WO 1993/006910 (15.04.1993 Gazette 1993/10)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL SE (30) Priority: 08.10.1991 US 19910772905 (71) Applicant: UNITED STATES ENVIRONMENTAL PROTECTION AGENCY an agency of the United States Government Research Triangle Park, North Carolina 27711 (US)	(72) Inventor: BURTON, Robert, M. Raleigh, NC 27607 (US) (74) Representative: MacDougall, Donald Carmichael, et al  Cruikshank & Fairweather 19 Royal Exchange Square Glasgow G1 3AE, Scotland Glasgow G1 3AE, Scotland (GB)