The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 29, 2005
Filed:
Nov. 08, 2002
Hye Kyung C. Timken, Albany, CA (US);
Hye Kyung C. Timken, Albany, CA (US);
Chevron U.S.A. Inc., San Ramon, CA (US);
Abstract
Improved silica-alumina catalyst compositions are methods for preparing such catalyst compositions are disclosed. The present invention relates to a method for preparing a highly homogeneous, amorphous silica-alumina cogel catalyst. Silica-alumina according to the present invention may be prepared by a variety of methods employing batch and continuous processes in different combinations. In one embodiment, a batch process, the present invention provides a method for preparing a highly homogenous silica-alumina cogel catalyst comprising: vigorously mixing an aqueous silicate solution with a gradual addition of an aqueous solution of an acid aluminum salt while maintaining the pH of the solution less than 3.0 and ensuring vigorous and complete mixing of the aluminum salt and silicate solutions to form an acidified silica sol in the aluminum salt solution; gradually adding a basic precipitant to the acidified silica sol/aluminum salt solution while vigorously mixing the solution to raise the pH of the cogel solution to greater than 3.0, producing a cogel; continuing the addition of basic precipitant and vigorous mixing of the cogel solution while maintaining a uniform pH of the cogel solution in the range of from 5-9 until precipitation of the cogel is complete; washing the precipitated cogel; and processing the precipitated cogel into a finished catalyst.