Study on hydrolysis of methyl acetate from production of pure terephalic acid by catalytic distillation

The effects of different cation-exchange resins on hydrolysis of methyl acetate (MeOAc) from production of pure terephalic acid were investigated in a batch stirred tank reactor, and it was found that the catalytic performance of macroreticular ion-exchange resin Amberlyst 35 for hydrolysis of methyl acetate was better. An experimental apparatus was set up and catalyst-bundles of ion exchange resin were packed in a column as a reaction zone. The effects of height of reaction and stripping zones, molar ratio of feed water to MeOAc (R_m), volume ratio of reflux to feed MeOAc (R_f) and space velocity (S_v) were investigated. The appropriate operation conditions were determined as follows- the feed positions of methyl acetate and water were at the bottom and top of the reaction section, respectively; six theoretical stages were assumed for reaction segment, whereas for striping section, five theoretical stages were specified; S_v was 0.36 h^-1, R_m was 5, R_f was 3. Under the conditions, the conversion of methyl acetate was 61.6%. The hydrolysis of MeOAc by catalytic distillation was simulated by Aspen Plus and the simulation results were in good agreement with the experimental results.