Pervaporation dehydration performance of microporous carbon membranes prepared from resorcinol/formaldehyde polymer

Microporous carbon membranes for pervaporation applications were prepared on a porous α-alumina support by a partially carbonization of a resorcinol/formaldehyde resin. The stability and dehydration performances of the carbon membranes were determined. The carbon membranes were used for the dehydration of several organic solvents (methanol, ethanol, i-propanol, and acetic acid) containing water; it was found that water was selectively permeated through the membrane and the separation factor increased with the molecular diameter of the organic solvents. The high selectivity to water can be explained by not only the hydrophilic nature of the pore surface but also the molecular sieving effect. Furthermore, the membranes showed high durability in the pervaporation of water/alcohol mixtures. On the other hand, the membranes were unstable in water/acetic acid mixture. However, the sulfonated carbon membranes were stable in pervaporation of water/acetic acid mixture and maintained their separation properties.