Cellulose Based Adsorbent Materials for the Dehydration of Ethanol Using Thermal Swing Adsorption

In this study, a thermal swing adsorption (TSA) column was used to evaluate the effectiveness of three ligno-cellulose based adsorbents on the removal of water from ethanol/water mixtures of 90, 95, and 97 wt% ethanol. The three adsorbents studied were bleached wood pulp, oak sawdust, and kenaf core. A glass adsorption column with an inside diameter of 2.54 cm was used to generate breakthrough curves to determine the effectiveness of the adsorbents and to allow comparability with starch based adsorbents that are currently used within the ethanol industry. Experimental results indicate that water is preferentially adsorbed allowing for complete dehydration of ethanol. Also, an evaluation has been made of the mass transport properties for the diffusion of water molecules into the porous matrices of the adsorbents as well as the length and velocity of the mass transfer zone.