Interdisciplinary Graduate Programme, Graduate College, Nanyang Technological University, Singapore 637553, Singapore; Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore.
Water Res. 2021 Jun 1;197:117103. doi: 10.1016/j.watres.2021.117103. Epub 2021 Apr 1.
The treatment of organic waste or wastewater with high organic solvent content has been challenging in industries as it cannot be done effectively using conventional wastewater treatment technologies such as biodegradation and advanced oxidation process. Solvent resistant membrane distillation (SR-MD) was proposed as an energy-efficient alternative to treat these waste streams but its application is hampered by the lack of solvent-resistant membranes, and there is a research gap in studying the feeds with water-solvent mixtures. In this work, ceramic tubular membranes with different pore sizes and structures were molecularly grafted with 1H,1H,2H,2H-perfluorodecyltriethoxysilane to obtain hydrophobic ceramic membranes for SR-MD. The modified membranes exhibited excellent hydrophobicity and solvent resistant properties, and they were tested for SR-MD performance with a wide range of dimethyl sulfoxide (DMSO) feed concentrations, from 3.5 to 85 wt%. The membranes exhibited a high DMSO rejection of >98% and the separation factor of >170, with permeation flux >4.4 kg m h when the DMSO concentration in feed was below 65 wt%. The separation performance was found strongly dependent on the evaporation step and the vapour-liquid equilibrium near the interface. The DMSO rejection was also comparable to pervaporation while the permeation flux was much higher at the feed concentration of 50 wt%. This study establishes the strategy of using SR-MD as a promising membrane process in treating complex industrial wastes with high organic solvent content.
用传统的废水处理技术（如生物降解和高级氧化工艺）处理高有机溶剂含量的有机废物或废水一直是工业界面临的挑战。溶剂耐受膜蒸馏（SR-MD）作为一种节能的替代方法被提出，用于处理这些废水，但由于缺乏耐溶剂膜，其应用受到阻碍，并且在研究水-溶剂混合物的进料方面存在研究空白。在这项工作中，不同孔径和结构的陶瓷管状膜用 1H、1H、2H、2H-全氟癸基三乙氧基硅烷进行分子接枝，得到用于 SR-MD 的疏水性陶瓷膜。改性膜表现出优异的疏水性和耐溶剂性能，并在宽 DMSO 进料浓度范围内（3.5 至 85wt%）对 SR-MD 性能进行了测试。当进料中 DMSO 浓度低于 65wt%时，膜表现出>98%的高 DMSO 截留率和>170 的分离因子，渗透通量>4.4kg m h。分离性能强烈依赖于蒸发步骤和界面附近的汽液平衡。DMSO 的截留率与渗透蒸发相当，而在进料浓度为 50wt%时，渗透通量要高得多。这项研究确立了使用 SR-MD 作为一种有前途的膜过程来处理高有机溶剂含量的复杂工业废物的策略。
