seen to continuously extract the pure maleic anhydride from maleic acid ra, which erhallits by dehydration of a vattenlosning of maleic acid in nervaro of a vattenupptagande / vattenextraherande resources

摘要

A process for recovering pure maleic anhydride, present in a crude mixture with an azeotropic entrainer and derived from the catalytic oxidation of benzene or C4 hydrocarbons, which comprises heating the mixture to decompose any residual maleic acid to maleic anhydride and water which is tied to or accompanies the entrainer, distilling the mixture in a column to recover the entrainer and water phase from the head of the column and produce a sump product free from the entrainer phase and distilling the sump product to recover the pure maleic anhydride.