反应详情

A process for producing tetrahydrofuran which comprises (1) continuously feeding and reacting 2-methyl-1,3-propanediol and acrolein to form 2-vinyl-5-methyl-1,3-dioxane in a condensation reaction zone; (2) continuously withdrawing the 2-vinyl-5-methyl-1,3-dioxane from said condensation reaction zone and continuously feeding the 2-vinyl-5-methyl-1,3-dioxane into a hydroformylation reaction zone to produce a mixture of 2-(5-methyl-1',3'-dioxane)propionaldehyde and 3-(5'-methyl-1',3'-dioxane)propionaldehyde in the presence of a hydroformylation catalyst at a temperature between about 25° and 200° C and a pressure between about 15 and 300 psi; (3) continuously withdrawing the propionaldehyde mixture and catalyst from the hydroformylation reaction zone; (4) continuously separating and recycling the hydroformylation catalyst to the hydroformylation reaction zone; (5) continuously feeding and contacting the propionaldehyde mixture with hydrogen in a hydrogenation zone in the presence of a hydrogenation catalyst at a temperature between about 180° and 225° C and a pressure between about 100 and 1000 psi in an aqueous medium maintained at a pH between about 0.2 and 3 with a water-soluble acid to produce a product mixture of tetrahydrofuran and 2-methyl-1,3-propanediol; (6) continuously recovering the tetrahydrofuran and 2-methyl-1,3-propanediol as separate components; and (7) continuously recycling the 2-methyl-1,3-propanediol to the first step condensation reaction zone.