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. 06, 1979
Filed:
Nov. 21, 1977
S Erik Pedersen, Havertown, PA (US);
Ming N Sheng, Cherry Hill, NJ (US);
Atlantic Richfield Company, Los Angeles, CA (US);
Abstract
A lower unsaturated aliphatic hydrocarbon of at least 4 carbon atoms and an oxygen-containing gas react to form maleic anhydride in the presence of a catalyst having the oxides of tungsten, phosphorus, thallium, and vanadium, said catalyst being a phosphotungstic catalyst modified by minor amounts of thallium oxide and vanadium oxide, the sum of the oxides of Tl and V constituting from 1% to 15% of the catalyst, the atom ratio of Tl:V being within a range from about 2:1 to about 8:1 and the overall atomic ratios are such that W:P:Tl:V corresponds to 1:0.1-0.7:0.01-0.16:0.01-0.1. Sometimes from about 3 to about 50 volume percent steam is added to the reactant stream to enhance catalyst stability and selectivity.