Ion-exchange membranes made of semi-interpenetrating polymer networks, used for pervaporation-assisted esterification and ion transport

Catalytic polymeric membranes: Preparation and application

“…One component of the blend should have the catalytic property while others should provide the separation properties to the blend. David et al [61] prepared ionic membranes by blending PVA with an ionic polymer (P). The ionic polymer was chosen in such a way that specific properties were imparted to the membrane.…”

“…In esterification processes, both inorganic and polymeric membranes have been used to increase the yield using pervaporation or vapor permeation arrangements. Pervaporation membrane reactors have been studied for esterification of oleic acid and ethanol [60], propionic acid and propanol [61], erucic acid and cetyl alcohol, tartaric acid and ethanol, oleic acid and butanol, and valeric acid and ethanol [62] with various acids or lipases as catalyst. This can be explained by the industrial importance of esters, the well-known reaction mechanisms and the availability of hydrophilic membranes which allow selective extraction of the produced water.…”

“…In the study of David et al [61] paratoluenesulfonic acid is used as an esterification catalyst and a hydrophilic membrane (GFT membrane) based on PVA was used to achieve the separation. It was observed that although the membrane was perfectly selective to water, after several runs, the flux increased while the selectivity decreased due to esterification of some OH -groups carried by the PVA chains by the acid.…”

Potential of Pervaporation and Vapor Separation with Water Selective Membranes for an Optimized Production of Biofuels—A Review

“…In this case, two membrane modules could be put in, making the clean-up or regeneration steps easier and, if a membrane fails, the chemical reactor can be maintained in operation in combination with the second one. Moreover, by using this configuration [57], it is possible to optimize independently both the selective and the catalytic properties. Instead, in the case the reactor and separation are integrated in one single unit (Figure 2b, TRPV or TRVP), the membrane is placed into the stirred reactor, in a flat or tubular configuration.…”

“…However, many other authors have developed membranes characterized by the selective layer with catalytic functionality, thus offering important advantages compared to conventional reactor set-up: this configuration may be considered promising to overcome the typical limits of catalytic reactors [57,[83][84][85][86][87][88][89][90]. Bernal et al [88] for example employed, for the first time, the H-ZSM5 zeolite membrane reactors (ZMR) in the continuous esterification of acetic acid with ethanol, by exploiting the lower diffusion resistance which a hybrid catalytic membrane reactor could offer assuring the immediate removal of the formed products and giving rise to higher turnover.…”