公开(公告)号：AU2003274707A1

公开(公告)日：2003-12-22

申请号：AU2003274707

申请日：2003-06-10

Applicant: BASF AG

Inventor： BOTTIKE NILS ,  FISCHER ROLF-HARTMUTH ,  WECK ALEXANDER ,  WINDECKER GUNTHER ,  HEYDRICH GUNNAR ,  HESSE MICHAEL ,  SCHLITTER STEPHAN ,  BORCHERT HOLGER ,  SCHUBERT MARKUS ,  ROSCH MARKUS

IPC: B01J23/80 ,  C07B61/00 ,  C07C29/149 ,  C07C31/20

Abstract: The present invention relates to a process for preparing optionally alkyl-substituted 1,4-butanediol by two-stage catalytic hydrogenation in the gas phase of C 4 -dicarboxylic acids and/or of derivatives thereof having the following steps: a) introducing a gas stream of a C 4 -dicarboxylic acid or of a derivative thereof at from 200 to 300° C. and from 2 to 60 bar into a first reactor and catalytically hydrogenating it to a product which contains mainly optionally alkyl-substituted gamma-butyrolactone; b) converting the product stream into the liquid phase; c) introducing the product stream obtained in this way into a second reactor at a temperature of from 100° C. to 240° C. and a pressure of from 20 to 250 bar and catalytically hydrogenating it in the liquid phase to optionally alkyl-substituted 1,4-butanediol; d) removing the desired product from by-products and any unconverted reactants; e) optionally recycling unconverted intermediates into one or both hydrogenation stages, said hydrogenation stages both using a catalyst which comprises =5% by weight, preferably from 5 to 95% by weight, in particular from 20 to 90% by weight, of a support, said second reactor having a higher pressure than said first reactor, and the product mixture removed from said first reactor being introduced without further purification into said second reactor.