Second interfacial polymerization of thin‐film composite hollow fibers with <scp>amine‐</scp>cyclodextrin<scp>s</scp> for pervaporation dehydration
Xi Yu, Tengyang Zhu, Sheng Xu, Xuan Zhang, Ming Yi, Shu Xiong, Shutong Liu, Liang Shen, Yan Wang
Abstract
Abstract High performance thin‐film composite (TFC) hollow fiber membranes have been developed for pervaporation dehydration by second interfacial polymerization (SIP) modification with three kinds of amine‐functionalized β ‐cyclodextrin (amine‐CDs), which were synthesized by modifying β ‐CD with ammonia, ethylenediamine (EDA), and tris(2‐aminoethyl)amine, respectively. The chemical properties of amine‐CDs and SIP‐modified TFC membranes were characterized by various techniques. The effects of amine‐CD type and SIP parameters (pH or concentration of CD‐EDA solution) were studied systematically to acquire the optimized selective layer of TFC membranes for ethanol dehydration. Among all SIP‐modified TFC membranes, the one with SIP by 2 wt% CD‐EDA aqueous solution (pH = 2) exhibited the most outstanding separation performance with a ultrahigh permeation flux (3,018.0 ± 12.0 g/m 2 hr) and permeate concentration (98.7 ± 0.2 wt% water) at 50°C (equivalent to separation factor of 415), contributed by the effectively incorporated CD with rich hydrophilic functional groups and intrinsic nanocavities facilitating the passage of water molecules.