Patent ID: RE39794

Claim:
A process for the co-production of maleic anhydride and at least one C 4 compound selected from the group consisting of butane-1,4-diol, γ-butyrolactone and tetrahydrofuran wherein: maleic anhydride is produced by steps comprising: supplying a source of gaseous oxygen and a hydrocarbon feedstock selected from C 4 hydrocarbons and benzene to a catalytic partial oxidation zone which contains a charge of a partial oxidation catalyst capable of effecting the partial oxidation of the hydrocarbon feedstock to form maleic anhydride and which is maintained under catalytic partial oxidation conditions; (ii) recovering from the partial oxidation zone a vaporous reaction effluent stream comprising maleic anhydride, water, unconverted hydrocarbon feedstock, and carbon oxides; (iii) condensing a part of the maleic anhydride present in the vaporous reaction effluent stream in a condensation zone to form a crude maleic anhydride stream; (iv) recovering from the condensation step (iii) a residual vaporous stream containing residual amounts of maleic anhydride; (v) absorbing further maleic anhydride from the residual vaporous stream of step (iv) by absorption in a liquid absorption medium selected from an organic solvent, water, and an aqueous solution; (vi) recovering from the absorption step (v) a loaded liquid absorption medium; and (vii) recovering maleic anhydride from the loaded liquid absorption medium; and wherein : said at least one C 4 compound selected from the group consisting of butane-1,4-diol, γ-butyrolactone and tetrahydrofuran is produced by steps comprising: (viii) providing a C 4+ hydrogenation feedstock selected from maleic anhydride, maleic acid, dialkyl maleates, monoalkyl maleates and mixtures of two or more thereof; (ix) supplying said C 4+ hydrogenation feedstock and hydrogen to a hydrogenation zone which contains a charge of a hydrogenation catalyst effective for catalytic hydrogenation of the C 4+ hydrogenation feedstock to yield said at least one C 4 product and which is maintained under catalytic hydrogenation conditions; and (x) recovering from the hydrogenation zone a hydrogenation product stream containing said at least one C 4 product; wherein crude maleic anhydride condensate of the crude maleic anhydride stream of condensation of maleic anhydride is effected in step (iii) in the presence of a liquid condensation medium consisting of a liquid selected from the group consisting of maleic anhydride, monoesters of maleic acid, diesters of maleic acid, and mixtures of two or more thereof, wherein the crude maleic anhydride stream of step ( iii ) is used as the C 4+ hydrogenation feedstock of step (viii) or is used to prepare the C 4+ hydrogenation feedstock of step (viii).