PROCESS FOR PREPARING GAMMA-BUTYROLACTONE, BUTANE-1,4-DIOL AND TETRAHYDROFURAN

摘要

A process is described for the production of at least one C4 compound select ed from butane-1,4-diol, ~-butyrolactone and tetrahydrofuran, which includes the step of hydrogenation in the vapour phas e of maleic anhydride in the presence of a heterogeneous hydrogenation catalyst, which process comprises: (a) contacting a vaporous stream containing maleic anhydride vapour, water vapour, and carbon oxides in an absorption zone with a high boiling organic solvent havi ng a boiling point at atmospheric pressure which is at least about 30 .degree.C higher than that of maleic anhydride thereby to form a solution of maleic anhydride in the high boiling organic solvent; (b) recovering from the absorption zone a waste gas stream; (c) contacting the solution of maleic anhydride in the high boiling solvent with a gaseous stream containing hydrogen thereby to strip maleic anhydride therefrom and to form a vaporous stream comprising hydrogen and maleic anhydride; (d) contacting material of the vaporous stream of step (e) in a hydrogenation zone under hydrogenation conditions in the presence of a heterogeneous hydrogenation catalyst thereby to convert maleic anhydride to at least one C4 compound selected from butane-1,4-diol, ~-butyrolactone and tetrahydrofuran; and (e) recovering fro m the hydrogenation zone a product stream containing said at least one C4 compound.