Patent ID: 6218334
Filing Date: 2001-04-17
Classification: B01J,C10G

Abstract:
A process for preparing a catalyst, which comprises:(a) extruding a matrix of a mixture of .lambda. transition alumina and .gamma. transition alumina;(b) depositing the following constituents on at least one of the .lambda. and .gamma. transition aluminas, wherein the percentages by weight are given are based on the total weight of the catalyst;from 0.01 to 2% by weight of silicon,from 0.1 to 15% by weight of at least one halogen selected from the group consisting of fluorine, chlorine, bromine and iodine,from 0.01 to 2% of at least noble metal selected from the platinum group,from 0.005 to 10% by weight of at least one promoter metal selected from the group consisting of tin, germanium, indium, gallium, thallium, antimony, lead, rhenium, manganese, chromium, molybdenum and tungsten, andoptionally, from 0.001 to 10% by weight of at least one doping metal selected from the group consisting of alkali metal, alkaline earth metals, lanthanide series metals, titanium, zirconium, hafnium, cobalt, nickel and zinc; and(c) hydrothermally treating the catalyst obtained after steps (a) and (b) at a temperature of from 300 to 1000.degree. C. in a gaseous atmosphere containing water vapor, wherein the molar content of water in the gaseous atmosphere is at least 0.05%; andwherein step (b) is prior to step (a); and wherein the catalyst, comprises:a matrix consisting of from about 1 to 99% by weight of .lambda. transition alumina, the complement, up to 100% by weight of the matrix, being .gamma. transition alumina; and, based on the total weight of the catalyst:from 0.01 to 2% by weight of silicon, from 0.1 to 15% by weight of at least one halogen selected from the group consisting of fluorine, chlorine, bromine and iodine;from 0.01 to 2.00% by weight of at least one noble metal selected from the platinum group,from 0.005 to 10% by weight of at least one promoter metal selected from the group consisting of tin, germanium, indium, gallium, thallium, antimony, lead, rhenium, manganese, chromium, molybdenum and tungsten, andoptionally, from 0.001 to 10% by weight of at least one doping metal selected from the group consisting of alkali metal, alkaline earth metals, lanthanide series metals, titanium, zirconium, hafnium, cobalt, nickel and zinc,said catalyst having been hydrothermally treated at a temperature of 300 to 1000.degree. C. in a gaseous atmosphere containing water vapor, wherein the molar content of water in the gaseous atmosphere is at least 0.05%.