Using poly(vinyldodecylimidazolium bromide) for the in-situ product recovery of n -butanol Rachel H. Vincent, J. Scott Parent and Andrew J. Daugulis* Department of Chemical Engineering, Queen’s University, Kingston, Ontario K7L 3N6, Canada The mitigation of end-product inhibition during the biosynthesis of n-butanol is demonstrated for an in-situ product recovery (ISPR) system employing a poly(ionic liquid) (PIL) absorbent. The thermodynamic affinity of poly(vinyldodecylimidazolium bromide) [P(VC 12 ImBr)] for n-butanol, acetone and ethanol versus water was measured at conditions experienced in a typical acetone-ethanol-butanol (ABE) fermentation. In addition to providing a high n-butanol partition coefficient (PC=6.5) and selectivity (α BuOH/water =46), P(VC 12 ImBr) is shown to be biocompatible with Saccharomyces cerevisiae and Clostridium acetobutylicum. Furthermore, the diffusivity of n-butanol in a hydrated PIL provides absorption rates that support ISPR applications. Using a 5 wt% PIL phase fraction relative to the aqueous phase mass, P(VC 12 ImBr) improved the volumetric productivity of a batch ABE ISPR process by 31% relative to a control fermentation. The concentration of n-butanol in the P(VC 12 ImBr) phase was sufficient to increase the alcohol concentration from 1.5 wt% in the fermentation medium to 25 wt% in the saturated PIL, thereby facilitating downstream n-butanol recovery. Keywords: n-butanol, ABE fermentation, Clostridium acetobutylicum, in-situ product recovery, polyionic liquid * Author for correspondence: Andrew J. Daugulis daugulis@queensu.ca RESEARCH ARTICLE Biotechnology Progress DOI 10.1002/btpr.2926 This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/btpr.2926 © 2019 American Institute of Chemical Engineers Received: Jul 18, 2019; Revised: Sep 17, 2019; Accepted: Sep 27, 2019 This article is protected by copyright. All rights reserved.