摘要:
A catalyst for the hydrogenation of C4-dicarboxylic acids and/or derivatives thereof, preferably maleic anhydride, in the gas phase comprises a) 20-94% by weight of copper oxide (CuO), preferably 40-92% by weight of CuO, in particular 60-90% by weight of CuO, and b) 0.005-5% by weight, preferably 0.01-3% by weight, in particular 0.05-2% by weight, palladium and/or a palladium compound (calculated as metallic palladium) and c) 2-79.995% by weight, preferably 5-59.99% by weight, in particular 8-39.95% by weight, of an oxidic support selected from the group consisting of the oxides of Al, Si, Zn, La, Ce, the elements of groups IIIA to VIIIA and of groups IA and IIA of the Periodic Table of the Elements.
摘要:
Optionally alkyl-substituted 1,4-butanediol is prepared from C4-dicarboxylic acids and/or of derivatives thereof by: a) a gas stream of the C4-dicarboxylic acid or the derivative thereof in a first reactor in the gas phase to obtain a product which contains mainly optionally alkyl-substituted γ-butyro-lactone; b) removing succinic anhydride from the product of step a); c) catalytically hydrogenating the product of step b) in a second reactor in the gas phase to obtain optionally alkyl-substituted 1,4-butanediol; d) removing the desired product from intermediates, by-products and any unconverted reactants; and e) optionally recycling unconverted intermediates into one or both hydrogenation stages. The catalysts employed in each of the hydrogenation stages comprise ≦95% by weight of CuO, and ≦5% by weight of an oxidic support, and the second reactor has a higher pressure than the first reactor.
摘要:
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 C4-dicarboxylic acids and/or of derivatives thereof having the following steps: a) introducing a gas stream of a C4-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 γ-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 ≦95% by weight, preferably from 5 to 95% by weight, in particular from 10 to 80% by weight, of CuO, and ≧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.
摘要:
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 C4-dicarboxylic acids and/or of derivatives thereof having the following steps: a) introducing a gas stream of a C4-dicarboxylic acid or of a derivative thereof at from 200 to 300° C. and from 10 to 100 bar into a first reactor or into a first reaction zone of a reactor and catalytically hydrogenating it in the gas phase to a product which contains mainly optionally alkyl-substituted γ-butyrolactone; b) introducing the product stream obtained in this way into a second reactor or into a second reaction zone of a reactor at a temperature of from 140° C. to 260° C. and catalytically hydrogenating it in the gas phase to optionally alkyl-substituted 1,4-butanediol; steps a) and b) being carried out at the same pressure; c) removing the desired product from intermediates, by-products and any unconverted reactants; d) optionally recycling unconverted intermediates into one or both hydrogenation stages, said hydrogenation stages each using a catalyst which comprises ≦95% by weight, preferably from 5 to 95% by weight, in particular from 10 to 80% by weight, of CuO, and ≧5% by weight, preferably from 5 to 95% by weight, in particular from 20 to 90% by weight, of an oxidic support, and the product mixture removed from the first hydrogenation stage being introduced without further purification into the second hydrogenation stage.
摘要:
A catalyst for the hydrogenation of C4-dicarboxylic acids and/or derivatives thereof, preferably maleic anhydride, in the gas phase comprises a) 20-94% by weight of copper oxide (CuO), preferably 40-92% by weight of CuO, in particular 60-90% by weight of CuO, and b) 0.005-5% by weight, preferably 0.01-3% by weight, in particular 0.05-2% by weight, palladium and/or a palladium compound (calculated as metallic palladium) and c) 2-79.995% by weight, preferably 5-59.99% by weight, in particular 8-39.95% by weight, of an oxidic support selected from the group consisting of the oxides of Al, Si, Zn, La, Ce, the elements of groups IIIA to VIIIA and of groups IA and IIA of the Periodic Table of the Elements.
摘要:
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 C4-dicarboxylic acids and/or of derivatives thereof having the following steps: a) introducing a gas stream of a C4-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 in the gas phase to a product which contains mainly optionally alkyl-substituted γ-butyrolactone; b) removing succinic anhydride from the product obtained in step a), preferably to a residual level of from
摘要:
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 C4-dicarboxylic acids and/or of derivatives thereof having the following steps: a) introducing a gas stream of a C4-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 7-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 ≦95% by weight, preferably from 5 to 95% by weight, in particular from 10 to 80% by weight, of CuO, and ≧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.
摘要:
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 C4-dicarboxylic acids and/or of derivatives thereof having the following steps: a) introducing a gas stream of a C4-dicarboxylic acid or of a derivative thereof at from 200 to 300° C. and from 10 to 100 bar into a first reactor or into a first reaction zone of a reactor and catalytically hydrogenating it in the gas phase to a product which contains mainly optionally alkyl-substituted y-butyrolactone; b) introducing the product stream obtained in this way into a second reactor or into a second reaction zone of a reactor at a temperature of from 140° C to 260° C. and catalytically hydrogenating it in the gas phase to optionally alkyl-substituted 1,4-butanediol; steps a) and b) being carried out at the same pressure; c) removing the desired product from intermediates, by-products and any unconverted reactants; d) optionally recycling unconverted intermediates into one or both hydrogenation stages, said hydrogenation stages each using a catalyst which comprises ≦95% by weight, preferably from 5 to 95% by weight, in particular from 10 to 80% by weight, of CuO, and ≧5% by weight, preferably from 5 to 95% by weight, in particular from 20 to 90% by weight, of an oxidic support, and the product mixture removed from the first hydrogenation stage being introduced without further purification into the second hydrogenation stage.
摘要:
Crude water-containing tetrahydrofuran is purified by passing the crude tetrahydrofuran through three distillation columns, withdrawing water from the bottom of the first column, recycling water-containing tetrahydrofuran from the top of the second column into the first column, passing a sidestream of the first column into the second column, recycling the bottom product of the third column into the first column, and withdrawing a distillate at the top of the first column. Additionally, a sidestream of the second column is passed into the third column and the purified tetrahydrofuran is recovered as the top product of the third column.
摘要:
A process for coproducing alkyl-substituted or unsubstituted THF and pyrrolidones by catalytically hydrogenating C4-dicarboxylic acids and/or derivatives thereof in the gas phase in the presence of copper catalysts and reacting GBL with ammonia or primary amines to give pyrrolidones.