| 摘要 |
The invention relates to a method for the production of optionally alkyl-substituted 1,4-butane-diol by two-step catalytic gas-phase hydrogenation of C4-dicarboxylic acids and/or the derivatives thereof, comprising the following steps: a) introduction of a gas flow of a C4-dicarboxylic acid or a derivative thereof into a first reactor and catalytic hydrogenation to form a mainly optionally alkyl- substituted gamma-butyrylactone product; b) conversion of said product flow into a liquid phase; c) introduction of the thus obtained product flow into a second reactor and catalytic liquid-phase hydrogenation to form optionally alkyl-substituted 1,4-butane-diol; d) separation of the desired product from secondary products and the optionally non-reacted; using a catalyst in both hydrogenation steps, which consists <= 95 wt. of a carrier, a higher pressure prevailing in the second reactor than in the first reactor, and the product mixture taken from the first reactor is introduced into the second reactor without any other purification. |
