Pervaporation with chitosan/hydroxyethylcellulose (CS/HEC) blended membranes

Chitosan/hydroxyethylcellulose (CS/HEC) blended membranes were prepared and crosslinked with a urea–formaldehyde–sulfuric acid mixture. The chemically crosslinking structure of blended membrane was analyzed by IR spectroscopy. The CS/HEC-3/1 and CS/HEC-9/1 blended membranes are appropriate for the dehydration of ethanol–water and isopropanol–water mixtures, respectively. These membranes have high selectivity and promising flux, especially at high alcohol concentration (e.g., J = 112 g m−2 h−1, separation factor (αw/e) = 10,491 for 90 wt.% ethanol solution and J = 175 g m−2 h−1, αw/i = 26091 for 90 wt.% isopropanol solution). Flux increased while the separation factor decreased with increasing water content in the feed. The pervaporation (PV) behavior of the isopropanol–water mixture is similar to that of the ethanol–water mixture. The effect of HEC on the sorption is an important factor for changes in the pervaporation performance of CS/HEC membranes.