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:
Nov. 26, 2002
Filed:
Nov. 04, 1998
Jeevan S. Abichandani, Voorhees, NJ (US);
Daria N. Lissy, Glen Mills, PA (US);
Mae K. Rubin, Bala Cynwyd, PA (US);
Sanjay B. Sharma, Burr Ridge, IL (US);
David S. Shihabi, Pennington, NJ (US);
Mobil Oil Corporation, Fairfax, VA (US);
Abstract
A shape-selective catalyst comprises a synthetic porous crystalline material having the structure of ZSM-5 and a composition involving the molar relationship: X O :(n)YO , wherein X is a trivalent element, such as aluminum, boron, iron and/or gallium, preferably aluminum; Y is a tetravalent element such as silicon and/or germanium, preferably silicon; and n is greater than about 12, and wherein the crystals have a major dimension of at least about 0.5 micron and a surface YO /X O ratio which is no more than 20% less than the bulk YO /X O ratio of the crystal. The crystals have a diffusion-modifying surface coating of a refractory material such as silica or coke. The catalyst is useful in a wide variety of selective hydrocarbon conversion processes, particularly the selective disproportionation of toluene to para-xylene.