Techno‐economic analysis of a lignocellulosic ethanol biorefinery with ionic liquid pre‐treatment

Abstract

Lignocellulose dissolution in ionic liquids is a relatively new biomass pre‐treatment technology that is receiving growing interest from the biofuels community as a route to provide readily‐hydrolyzable holocellulose. Despite its proven advantages over other pre‐treatment technologies – including feedstock invariance, high monomeric sugar yields over short saccharification times, and extensive delignification – there are several core issues that stand in the way of commercialization. These include the relative high cost of the ionic liquids themselves, a lack of knowledge in terms of process considerations for a biorefinery based on these solvents, and scant information on the coproducts this pre‐treatment technology could provide to the marketplace. We present an initial techno‐economic model of a biorefinery that is based on the ionic liquid pre‐treatment technology and have identified, through a comprehensive sensitivity analysis, the most significant areas in terms of cost savings/revenue generation that must be addressed before ionic liquid pre‐treatment can compete with other, more established, pre‐treatment technologies. This report evaluates this new pre‐treatment technology through the perspective of a virtual operating biorefinery, and although there are significant challenges that must be addressed, there is a clear path that can enable commercialization of this novel approach. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd