Competitive Adsorption of Butanol from ABE Fermentation Solution by Silicalite-1

Abstract

Biobutanol is an alternative energy that has been of great interest as a substitute for fossil fuel. It can be obtained from acetone-butanol-ethanol (ABE) fermentation with by-products of acetone and ethanol. In this work, the competitive kinetics of adsorption of butanol from ABE model solution was investigated on Silicalite-1 comparing to commercial ZSM-5. The adsorption was conducted in liquid phase and batch mode at 25°C between 0−90 min with the composition of ABE model solution of 1, 2, 0.33 wt% (acetone, butanol, ethanol) in aqueous solution. The Silicalite-1 shows fast adsorption of butanol from 0.5 min and possesses high adsorption capacity of 0.15 g/g, which is higher than that of the ZSM-5, 0.12 g/g. The Silicalite-1 exhibits high affinity to butanol > acetone > ethanol with selectivity of butanol-to-acetone (SB/A) of 2.6 and butanol-to-ethanol (SB/E) of 13.8. The good performance of Silicalite-1 adsorbent could be related to its hydrophobicity and higher micropore surface area and micropore volume as compared to ZSM-5.