文献类型：期刊文献

英文题名：Recovery of dilute aqueous butanol by membrane vapor extraction with dodecane or mesitylene

作者：Chen, J.[1,2];Razdan, N.[1];Field, T.[1];Liu, D. E.[1];Wolski, P.[1];Cao, X.[2];Prausnitz, J. M.[1];Radke, C. J.[1]

机构：[1]Univ Calif Berkeley, Chem & Biomol Engn Dept, 101E Gilman Hall, Berkeley, CA 94720 USA;[2]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2017

卷号：528

起止页码：103

外文期刊名：JOURNAL OF MEMBRANE SCIENCE

收录：;EI(收录号：20170403276281);WOS:【SCI-EXPANDED(收录号:WOS:000395956400011)】；

基金：The authors are grateful to the Energy Bioenergy Institute of the University of California for use of facilities and to Stefan Bauer for essential advice on chemical analyses. J. Chen acknowledges the China Scholarship Council for financial assistance during her stay at the University of California, Berkeley. D.E. Liu received partial support from Chevron Technology Corporation, Richmond, CA.

语种：英文

外文关键词：Membrane vapor extraction; Mass-transfer resistance; Butanol or furfural recovery; Recirculation flow cell; Dodecane; Mesitylene

摘要：A novel, nearly isothermal, nonselective-membrane separation process, membrane vapor extraction (MITE), efficiently recovers butanol from a dilute aqueous solution, for example, from a fermentation broth (Liu et al., 2015). In MVE, feed and solvent liquids are not in contact; they are separated by vapor. Therefore, compared to conventional extraction, MVE avoids formation of difficult-to-separate emulsions. In MVE, a semi-volatile aqueous solute (e.g., butanol) vaporizes at the upstream side of a membrane, diffuses as a vapor through the membrane pores, and subsequently condenses and dissolves into a high-boiling nonpolar solvent, favorable to the solute but not to water. Design analysis of a 1.5-m long, 30-m(2) membrane-area countercurrent MVE unit for processing 2-wt% aqueous butanol by dodecane solvent at 40 degrees C indicates over 90% recovery of the feed butanol with essentially no water loss and with very low energy requirement (Liu et al, 2015). The separation factor is over 1500. However, the published design study gives no experimental evidence for the calculated MITE separation. Here, we present experimental data to validate the MITE process. We use an omniphobic (i.e., hydrophobic and oleophobic), 0.2-mu m pore-diameter Versapor (R) 200 R membrane (Pall Corporation, Exton, PA) housed in a 6-cm wide by 10-cm long plate-and-frame channeled flow cell with 0.8-cm gap thickness. Membrane transfer area is 28 cm(2). The membrane flow cell is designed for minimal axial concentration change and is operated in the transient mode between two recirculating flow loops. 2-wt% aqueous butanol is extracted into dodecane or mesitylene at 25 or 40 degrees C. Also, 1.5-wt% furfural is extracted into dodecane at 40 degrees C. Since vapor transport across the membrane contributes minimal resistance, MVE performance is governed by mass transfer through feed and solvent boundary layers. Mass-transfer coefficients are determined from the Graetz-Leveque analysis of laminar thin-slit flow (Bird et al., 2002). Predicted extraction performance agrees well with experiment using no adjustable parameters. Consistent with the initial multistage-design analysis (Liu et al., 2015), our new bench-scale experimental results confirm that MVE is a viable separation process to recover dilute semi-volatile biosolutes from water with minimal energy requirement. Preliminary analysis of downstream solute recovery from the extract via distillation is more efficient than that for pervaporation because of insignificant water carry over through the MVE membrane.