In their layout, the first chemical reactor was operated in batch mode, and the reaction product
was recycled by the first pervaporation unit to reduce the water contents without significant
concentration changes. The second pervaporation unit was used to completely dehydrate a bleed
stream from the first pervaporation unit. This stream was then further processed in the second
reactor that was similar to the first, also being combined with two pervaporation units for
recirculation and dehydration. It was possible to achieve a conversion rate of 97% and final water
concentration of less than 0.5 wt% this process has been reported on the application for a medium
size esterification plant. The plant was operated in batch mode for the production of various
esters. The construction of a larger plant using the hybrid process combining batch and cascade
operation was scheduled.
Till now there are no published studies on using pervaporation-esterification reactor hybrid
process for the esterification of EG and TPA. This may be due to the solid state of TPA and the
related operational problems in addition to the non-availability of a suitable membrane for the
pervaporation unit. In this case, the concept of pervaporation-esterification reactor hybrid process