Conversion of the Acetone–Butanol–Ethanol (ABE) Mixture to Hydrocarbons by Catalytic Dehydration

An acetone–butanol–ethanol (ABE) mixture, containing 62.9 wt % n-butanol, 29.3 wt % acetone, and 7.8 wt % ethanol, can be produced from biomass through the well-established ABE fermentation process using genetically modified Clostridium acetobutylicum. In this work, the catalytic dehydration reactions of the ABE mixture are studied to deoxygenate the mixture. A feed of the ABE mixture was preheated and pumped through a catalytic packed bed tubular reactor in a continuous process at pressures of 3–13 bar. Experiments were run at different operating temperatures and feed flow rates to observe the effect on the dehydration products, which are mixtures of three phases: (1) a gas phase consisting of light hydrocarbons and carbon dioxide, (2) an organic liquid phase consisting of heavy hydrocarbons, and (3) an aqueous phase with dissolved oxygenated hydrocarbons. The products were analyzed and compared to those from the dehydration of pure n-butanol, acetone, and ethanol feedstocks. The conversion is examined o...