PROCESS FOR PRODUCING 1,4-BUTANEDIOL, GAMMA-BUTYROLACTONE AND TETRAHYDROFURAN BY HYDROGENATING DIALKYL MALEATE IN MIXED LIQUID/VAPOR PHASE

摘要

A process for the production of 1,4-butanediol and tetrahydrofuran by catalytic hydrogenation of dialkyl maleates includes the following steps: a) hydrogenating a stream of dialkyl maleate in a first stage of reaction over suitable catalysts to produce dialkyl succinate; b) further hydrogenating the dialkyl succinate in a second stage of reaction, by using a different suitable catalyst, for producing mainly 1,4-butanediol, together with gamma-butyrolactone and tetrahydrofuran as co-products. In both stages of reaction the conditions, as hydrogen/organic feed ratio, pressure and temperature, are such to maintain the reactors in mixed liquid/vapor phase.