Patent ID: 6245704
Filing Date: 2001-06-12
Classification: B01J,C07C,C10G

Abstract:
A catalyst comprising a matrix, a MFI zeolite and at least one group VIII element, wherein crystals of the MFI zeolite are dealuminated on outer surfaces by at least one treatment with at least one solution of a fluorosilicate having a cation which is NH.sub.4.sup.+, an alkylammonium, K.sup.+, Na.sup.+, Li.sup.+, Ba.sup.2+, Mg.sup.2+, Cd.sup.2+, Cu.sup.+, Cu.sup.2+, Ca.sup.2+, Cs.sup.+, Fe.sup.2+, Co.sup.2+, Pb.sup.2+, Mn.sup.2+, Rb.sup.2+, Ag.sup.+, Sr.sup.2+, Zn.sup.2+, Tl.sup.+, or H.sup.+, the overall dealumination of said zeolite thus treated being less than 5 percent on an atomic basis, wherein the MFI zeolite prior to treatment with fluorosilicate has an atomic Si/Al ratio of 5 to less than 100.