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. 28, 1999
Filed:
Mar. 19, 1999
Manfred J Bergfeld, Erlenbach-Mechenhard, DE;
Kurt Uihlein, Grossheubach, DE;
Akzo Nobel NV, Arnhem, NL;
Abstract
A process for manufacturing gamma-butyrolactone by the catalytic hydrogenation of maleic anhydride, succinic anhydride or their acids in the vapor phase in the presence of catalysts based on copper oxide and aluminum oxide in reduced form is described. The process is characterized in that a catalyst is employed to conduct the reaction which is formed on the basis of 50 to 95 % by weight copper oxide, 3 to 30 % by weight aluminum oxide and 0 to 25 % by weight of a binder. Preferably the catalyst is formed on the basis of 83.5 to 85.5 % by weight copper oxide, 9 to 11 % by weight aluminum oxide, and 4.5 to 6.5 % by weight graphite. The reaction mixture obtained can be used directly without separating off the water, e.g. for manufacturing N-methylpyrrolidone.