(19)

(11)

EP 2 744 976 A1

(12)

(43) Date of publication: 25.06.2014 Bulletin 2014/26 (21) Application number: 12864952.2 (22) Date of filing: 13.12.2012

(51) International Patent Classification (IPC):  E21B 43/22(2006.01) C09K 8/26(2006.01) C09K 8/035(2006.01) (86) International application number: PCT/US2012/069350 (87) International publication number: WO 2013/106156 (18.07.2013 Gazette 2013/29)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR (30) Priority: 14.12.2011 US 201161570664 P (71) Applicant: Shell Internationale Research Maatschappij B.V. 2596 HR The Hague (NL)	(72) Inventors: TAYLOR, Richard Bruce Sugar Land, Texas 77479 (US) BLOM, Carolus Petrus Adrianus Muscat 113 (OM) BOERRIGTER, Paulus Maria Sultanate of Oman PC 116 (OM) HEDDEN, Ralf NL-2289 EE Rijswijk (NL) (74) Representative: Matthezing, Robert Maarten et al Shell International B.V. Intellectual Property Services P.O. Box 384 2501 CJ The Hague 2501 CJ The Hague (NL)