| abstract |
A process is described for the production of butane-1,4-diol, η-butyrolactone and/or tetrahydrofuran. A vaporous stream containing maleic anhydride, water, and carbon oxides is contacted in an absorption zone with a high boiling ester as solvent to form a solution of maleic anhydride in the high boiling ester which has a boiling point at the atmospheric pressure at least about 30 °C higher than that of maleic anhydride and is selected from di-(C1 to C4 alkyl) esters of alkyl dicarboxylic acids containing up to 13 carbon atoms, mono- and di-(C10 to C18 alkyl) esters of maleic acid, fumaric acid, succinic acid, and mixtures thereof, (C1 to C4 alkyl) esters of naphthalene-monocarboxylic acids, tri-(C1 to C4 alkyl) esters of aromatic tricarboxylic acids, and di-(C1 to C4 alkyl) esters of isophthalic acid. The maleic anhydride in the solution is stripped with a gaseous stream containing hydrogen thereby forming a vaporous stream comprising hydrogen and maleic anhydride, which is contacted in a hydrogenation zone with a heterogeneous hydrogenation catalyst to convert maleic anhydride to at least one C4 compound selected from butane-1,4-diol, η-butyrolactone and tetrahydrofuran. |