Preparation and characterization of cassava starch-based adsorbents for separating of azeotropic ethanol-water in biofuels ethanol production

Background Dehydration of biomass-based fermentation product is an essential process in the production of biofuels ethanol for industrial applications. Cassava starch, an adsorbent with high efficiency, can be fermented after saturating with water, which overcomes the shortcomings of high energy consumption bioethanol production. Therefore, the aim of the present study was to prepare cassava starch-based adsorbents with high adsorption efficiency that do not affect fermentative production. Results Porous cassava starch granules, which can be fermented to produce biofuel ethanol, were formed through the partial hydrolysis of starch using amylase and ultrasonication. The structural changes in cassava starch granules were also studied to prove that porous starch could be reused as feedstock for biomass-based fuel ethanol production after adsorption. Finally, an adsorption experiment proved that the modified cassava adsorbents had better absorptive properties than the native cassava. Conclusion These structural changes in cassava starch granules showed that porous starch is an efficient adsorbent that can be reused after adsorption as feedstock for fuel ethanol, which increases the energy efficiency of ethanol–water azeotrope separation. © 2015 Society of Chemical Industry