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:
Dec. 08, 1992
Filed:
Mar. 06, 1991
Kenji Ueda, Hyogo, JP;
Tatsuya Kawabata, Hyogo, JP;
Masaaki Okuno, Hyogo, JP;
Chisako Nishio, Kanagawa, JP;
Shinya Tanaka, Hyogo, JP;
Nippon Shokubai Kagaku Kogyo Co., Ltd., Osaka, JP;
Abstract
The invention presents catalysts for producing phthalic anhydride by vapor phase catalytic oxidation of orthoxylene and/or naphthalene with molecular oxygen or gas containing molecular oxygen. The catalyst is prepared by supporting a catalytic active substance comprising 1 to 20 parts by weight (hereinafter abbreviated 'parts') of vanadium oxide as V.sub.2 O.sub.3, 99 to 80 parts of anatase type titanium dioxide with specific surface area of 10 to 60 m.sup.2 /g as TiO.sub.2 and per 100 parts of the sum of these two ingredients, 0.05 to 1.2 parts of at least one element selected from potassium, cesium, rubidium and thallium as oxide, and 0.05 to 2 parts of silver as Ag.sub.2 O on a heat resistant inorganic carrier. The catalyst may also contain, per 100 parts in total of vanadium oxide and titanium dioxide, 0 to 1 part of niobium as Nb.sub.2 O.sub.5, 0 to 1.2 parts of phosphorus as P.sub.2 O.sub.3, and 0 to 5 parts of antimony as Sb.sub.2 O.sub.3 (however, contents of niobium, phosphorus and antimony will not be zero at the same time).