Polyvinyl alcohol and graphene oxide blending surface coated alumina hollow fiber (AHF) membrane for pervaporation dehydration of epichlorohydrin(ECH)/ isopropanol(IPA)/water ternary feed mixture Shivshankar Chaudhari a , DongWook Chang a , KieYong Cho a , MinYoung Shon a, *, YongSung Kwon b , SeungEun Nam b , YouIn Park b a Department of Industrial Chemistry, Pukyong National University, San 100, Yongdang-Dong, Nam-Gu, Busan 608-739, Republic of Korea b Center for membranes, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 305-600, Republic of Korea ARTICLE INFO Article History: Received 20 July 2020 Revised 11 September 2020 Accepted 11 September 2020 Available online xxx ABSTRACT For pervaporation dehydration of ternary azeotropes ECH/IPA/water (50/30/20, w/w,%) produced in epoxy resin manufacturing process, Graphite nanopowder was oxidized to prepare graphene oxide (GO) nano- sheets, which were incorporated into a polyvinyl alcohol (PVA)-tetraethyl orthosilicate (TEOS) solution. The GO-PVA-TEOS solution was coated on the surface of a nanoporous alumina hollow fiber (AHF) membrane. The pore size and element composition on the AHF were determined using FE-SEM and energy dispersive spectroscopy. The coating thickness of the GO-PVA-TEOS membrane layer on the AHF was measured using FE-SEM analysis, and XPS, FTIR analysis of the membrane was conducted to confirm the condensation reac- tion between PVA and TEOS. Pervaporation dehydration of the epichlorohydrin/ isopropanol/water mixtures was conducted using the AHF membranes with and without GO in PVA-TEOS. For pervaporation output, with the addition of 0À1.5 wt% GO in the PVA-TEOS, it was quantitatively reported that the flux declined from 0.17 to 0.09 kg/m 2 h and the separation factor increased sharply from 1450 to 4844 with feed consisting of the ECH/IPA/water (50/30/20, w/w,%) solution at 30 °C. In terms of the long-term (240 h) pervaporation stability evaluation of 1.0 wt% GO-incorporated membrane, the excellent separation efficiency with increased of flux was obtained. © 2020 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Keywords: Pervaporation Polyvinyl alcohol (PVA) Graphene oxide Surface coating Epichlorohydrin Alumina hollow fiber 1. Introduction Epichlorohydrin (ECH) is a key industrial chemical used in the production of epoxy resin and glycerin and comprises organochlorine moieties in its formula [1]. In the manufacturing process of epoxy resin, initially, the bisphenolÀA, an isopropanol (IPA) used as a sol- vent in excess of epichlorohydrin, in comparison to bisphenol (1:4), is charged as a precursor. [2] During the conversion of bisphenol-A to the epoxy resin polymer, water and a series of ECH impurities are formed along with the final epoxy resin product. Generally, during the recovery of ECH and IPA from the final product, ECH-rich impuri- ties can be readily removed by the distillation process; however, the ECH, IPA, and water form an azeotropic mixture of composition 50/ 30/20 ECH/IPA/water (w/w,%) with a high reflux ratio. ECH and IPA can be re-used in the reaction but they should be moisture-free. Therefore, azeotropic distillation has been generally carried out; however, it leads to higher energy consumption and higher manufacturing cost for the product. Additionally, because ECH is a carcinogenic compound and because of the environmental hazards thereof, it cannot be treated as an effluent [3À5]. Thus, a novel hybrid approach is necessary to remove the moisture through the hydro- philic membrane via pervaporation and develop a moisture-free ECH/IPA mixture that can be easily separated using distillation to increase product competitiveness by reducing the energy require- ment. Fig. 1 shows the estimated energy consumption comparison between the traditional distillation and hybrid processes of pervapo- ration and distillation for separation of the ECH/IPA/water mixture at their azeotropic point (50/30/20 w/w,%) based on theoretical simula- tion study done by Korea Research Institute of Chemical Technology. It can be seen from Fig. 1 that, in the hybrid process, by replacing one column with pervaporation, the energy consumption is reduced by 23% compared with that for the conventional distillation process. Nevertheless, it is well-known that ECH is a highly reactive com- pound [6]; hence, choosing a membrane material for pervaporation separation of ECH containing feed is challenging. Given these, the membrane material must have superior ECH resistance along with good mechanical properties. Because of its excellent film-forming properties, polyvinyl alcohol (PVA) has been regarded as a very promising hydrophilic membrane material for membrane-based * Corresponding author. E-mail address: myshon@pknu.ac.kr (M. Shon). https://doi.org/10.1016/j.jtice.2020.09.016 1876-1070/© 2020 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. ARTICLE IN PRESS JID: JTICE [m5G;September 29, 2020;11:50] Please cite this article as: S. Chaudhari et al., Polyvinyl alcohol and graphene oxide blending surface coated alumina hollow fiber (AHF) membrane for pervaporation dehydration of epichlorohydrin(ECH)/ isopropanol(IPA)/water ternary feed mixture, Journal of the Taiwan Institute of Chemical Engineers (2020), https://doi.org/10.1016/j.jtice.2020.09.016 Journal of the Taiwan Institute of Chemical Engineers 000 (2020) 1À12 Contents lists available at ScienceDirect Journal of the Taiwan Institute of Chemical Engineers journal homepage: www.elsevier.com/locate/jtice