Metal-organic frameworks (MOFs) are an emerging class of crystalline microporous materials, which have drawn considerable attention for separation applications. While a number of successful examples of MOF-based membranes for gas separation have been reported, only a few of pure MOF membranes presented high performance in pervaporation. This work reports on the application of a highly hydrophilic MOF, MOF-303, for dehydration of ethanol as well as isopropanol (IPA) via pervaporation. Dense MOF-303 membranes are fabricated with either a sodium hydroxide or urea solution. The latter recipe renders MOF-303 crystals a low quantity of missing linker; and it also yields a membrane with fewer pinhole-type defects. The MOF-303 membrane prepared with urea presents a relatively low air permeance and a much higher separation performance for of water-ethanol and water-IPA mixtures, as compared to that synthesized with sodium hydroxide. The MOF-303-urea membrane possesses high separation factors for water/ethanol (55349) and for water/IPA (3801) at 303 K. At a higher temperature of 343 K, this membrane still offers a good water/ethanol separation factor of 1874. A 7-day pervaporation operation on the MOF-303-urea membrane demonstrates that the separation performance drops gradually during the test, but it can be restored via thermal treatment on the membrane. Molecular simulations are performed to shed light on the transport behavior of water, ethanol, and IPA in MOF-303. The computational results suggest that the dehydration capability of this MOF can be attributed to both of its water-selective adsorption and diffusion, particularly the latter. Specifically, a relatively high diffusion barrier to the alcohols in MOF-303 results in the high selectivity of water over ethanol or IPA.

金属有机框架（MOFs）是一类新兴的结晶微孔材料，在分离应用中引起了相当大的关注。虽然已经报道了许多基于 MOF 的气体分离膜的成功例子，但只有少数纯 MOF 膜在全蒸发方面表现出高性能。这项工作报告了高亲水性 MOF MOF-303 通过全蒸发对乙醇和异丙醇 (IPA) 进行脱水的应用。致密 MOF-303 膜由氢氧化钠或尿素溶液制成。后一种配方使 MOF-303 晶体缺少少量的接头；并且它还产生具有较少针孔型缺陷的膜。与氢氧化钠合成的膜相比，用尿素制备的 MOF-303 膜具有较低的透气性，对水-乙醇和水-异丙醇混合物的分离性能要高得多。MOF-303-尿素膜在 303 K 时对水/乙醇 (55349) 和水/IPA (3801) 具有较高的分离系数。在 343 K 的较高温度下，该膜仍能提供良好的水/乙醇分离系数1874. 对 MOF-303-脲膜进行为期 7 天的全蒸发操作表明，在测试过程中分离性能逐渐下降，但可以通过对膜进行热处理来恢复。进行分子模拟以阐明 MOF-303 中水、乙醇和 IPA 的传输行为。计算结果表明，这种 MOF 的脱水能力可归因于其对水的选择性吸附和扩散，尤其是后者。具体而言，MOF-303 中对醇类的相对高扩散屏障导致水对乙醇或 IPA 的高选择性。