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:
Feb. 22, 1994
Filed:
Mar. 15, 1993
Ikuya Matsuura, Toyama, JP;
Maruzen Petrochemical Co., Ltd., Tokyo, JP;
Abstract
The present invention provides a process for the manufacture of maleic anhydride by the vapor phase catalytic oxidation of n-butane with molecular oxygen by the use of a specially prepared phosphorus vanadium-oxygen composite catalyst containing specific kind of a divalent metal. The catalyst used in the present invention is prepared from a mixture of vanadyl hydrogen orthophosphate and at least one compound selected from the group consisting of a divalent metal hydrogen orthophosphate (Divalent metal is selected from Mg, Ca, Ba, Mn, Fe, Co, Ni, Cu, and Zn.), a divalent metal ammonium orthophosphate (Divalent metal is the same as above.), and a divalent metal orthophosphate (Divalent metal is the same as above.), with the atomic ratio of the divalent metal/vanadium of 0.003-0.5, by calcining the mixture at 300.degree.-400.degree. C., and then pretreating said catalyst in an inert gas or a mixed gas containing n butane and molecular oxygen at 350.degree.-700.degree. C. Maleic anhydride can be manufactured at a high conversion, a high selectivity and a high yield according to the present invention.