Wang Ji-Ting, Huang Zhen, Zhu Ya-Tong, Wang Si Ning
Department of Packaging Engineering, Tianjin University of Commerce, Tianjin 300134, P.R. China.
Turk J Chem. 2023 Aug 23;47(6):1389-1406. doi: 10.55730/1300-0527.3622. eCollection 2023.
In this study, mixed matrix membranes (MMMs) composed of poly(vinyl alcohol) (PVA) and porous ZSM-5 zeolite are thoroughly investigated for concentrating alcohols of ethanol and n-propanol via dewatering pervaporation. The effects of the zeolite content (10-30 wt.%), feed composition (5-30 wt.% water), and feed temperature (50-90 °C) on the pervaporation flux/separation factor and component permeance/selectivity of these MMMs are examined in detail. These MMMs achieve higher separation efficiency and pervaporation flux than their pure PVA counterparts as expected, even if the dehydration results strongly depend on the pervaporation conditions. The disparity in pervaporation performances acquired for different alcohol solutions may be understood in terms of polarity and molecular size, which differ among these alcohol molecules. The PVA/zeolite MMM of 20 wt.% ZSM-5 zeolite content performs substantially stably at 60 °C for the feed with 80 wt.% alcohol while maintaining separation factors of 660 or 820 and total fluxes of 970 or 825 g/mh for dewatering water/ethanol and water/n-propanol, respectively. Thus, our membranes appear to be technically feasible for practical alcohol dehydration uses.
在本研究中，对由聚乙烯醇（PVA）和多孔ZSM-5沸石组成的混合基质膜（MMM）进行了深入研究，以通过脱水渗透蒸发来浓缩乙醇和正丙醇。详细考察了沸石含量（10-30 wt.%）、进料组成（5-30 wt.%水）和进料温度（50-90 °C）对这些MMM的渗透蒸发通量/分离因子以及组分渗透率/选择性的影响。正如预期的那样，这些MMM比纯PVA膜具有更高的分离效率和渗透蒸发通量，即使脱水结果在很大程度上取决于渗透蒸发条件。对于不同醇溶液获得的渗透蒸发性能差异，可以根据这些醇分子之间不同的极性和分子大小来理解。含20 wt.% ZSM-5沸石的PVA/沸石MMM在60 °C下对含80 wt.%醇的进料基本稳定运行，对于水/乙醇和水/正丙醇脱水，分离因子分别保持在660或820，总通量分别为970或825 g/m²·h。因此，我们的膜对于实际的醇脱水应用在技术上似乎是可行的。
