文件类型:PDF文档
文件大小:650K
The present invention relates to a process for preparing unsubstituted or C1-C4-alkyl-substituted gamma-butyrolactone by catalytic hydrogenation of maleic acid and/or its derivatives in the presence of chromium-free catalyst comprising from 10 to 80% by weight of copper oxide and from 10 to 90% by weight of at least one catalyst support selected from the group consisting of silicon dioxide, titanium dioxide, hafnium dioxide, magnesium silicate, activated carbon, silicon carbide, zirconium dioxide and alpha-aluminum oxide.