Desiccant from Cassava for Dehydration of Alcohol Vapor at Near Azeotropic Concentration

Abstract

Wet cassava pulp is generated in large quantity during a production of cassava starch. Major utilization of the pulp is in animal feed manufacturing. During a period of low demand, this material could accumulate and decompose causing air pollution in areas surround the starch factories. This research used biomass desiccant prepared from cassava pulp in a bench-scale packed-bed adsorption system to study the dehydration of ethanol and n-propanol vapor at concentration near their azeotropic points. The sorption capacity was found to be 0.053 and 0.119 gwater/gdesiccant for ethanol and iso-propanol at concentration of 80 %(w/w) and 0.109 gwater/gdesiccant for n-propanol at concentration of 65 %(w/w). Alcoholic solutions with concentration higher than their aqueous azeotropic points, which could not be achieved by normal fractional distillation, were obtained in all the experiments. This study elucidates that cassava pulp could be value-added, and water adsorption using cassava-derived desiccant could be an alternative technique for production of high purity alcohols.