Patent ID: 7147769

Claim:
A method for the production of a composition comprising: (a) admixing: 1) a liquid, 2) a zinc-containing compound, 3) a silica-containing material, and 4) alumina so as to form a mixture thereof; (b) drying said mixture so as to form a first dried mixture; (c) calcining said first dried mixture so as to form a first calcined mixture; (d) incorporating a promoter into or onto said first calcined mixture so as to form a promoted mixture; (e) contacting said promoted mixture with an acid selected from the group consisting of citric acid, tartaric acid, and combinations thereof to form a contacted mixture; (f) drying said contacted mixture to form a second dried mixture; (g) calcining said second dried mixture so as to form a second calcined mixture; (h) reducing said second calcined mixture with a suitable reducing agent under suitable conditions to produce a composition having a reduced valence promoter content therein, and (i) recovering said composition.