Production of maleic anhydride by azeotropic dehydration of maleic acid solutions derived from benzene oxidation processes

摘要

Maleic acid is recovered from aqueous solutions containing benzoquinone especially from a catalyst benzene oxidation process by: P PA. CONCENTRATING AN AQUEOUS MALEIC ACID SOLUTION CONTAINING BENZOQUINONE;PPB. ADDING FROM 0.1 TO 2.0 WEIGHT PERCENT OF PHTHALIC ACID OR ITS ANHYDRIDE, BASED ON THE WEIGHT OF MALEIC ACID, TO THE CONCENTRATED SOLUTION FROM (A); THEREAFTERP PC. SEPARATING THE MALEIC ACID FROM THE MIXTURE FROM (B) BY CONTINUOUS DISTILLATION WITH AN ORGANIC SOLVENT AND PURIFYING THE SEPARATED MALEIC ACID.