自支撑NH2-MIL-125/聚噁二唑复合正渗透膜的制备及性能

合成了高强度亲水性含羧基聚噁二唑材料(POD-COOH)和含氨基金属有机框架材料(NH₂-MIL-125), 以NH₂-MIL-125为填料, 与POD-COOH基体材料进行溶液共混, 并通过溶液浇铸法制备系列新型自支撑复合正渗透膜, 研究NH₂-MIL-125的引入对复合正渗透膜结构和性能的影响. 研究结果表明, 所制备的系列复合正渗透膜均呈致密结构, 且随着NH₂-MIL-125含量的增加, 复合膜的表面亲水性增加、 电负性增强, 并保持良好的机械性能. 以去离子水为进料液, 1.5 mol/L硫酸钠溶液为汲取液, 对上述自支撑复合膜进行正渗透性能测试, 发现由于消除了传统正渗透膜支撑层的内浓差极化现象, 该新型复合正渗透膜在分离过程中具有优异的正渗透性能.

Preparation and Performance of Self-standing NH2-MIL-125/polyoxadiazole Composite Forward Osmosis Membranes †

A high-strength hydrophilic carboxyl-containing polyoxadiazole material(POD-COOH) and an amino-containing metal organic frame material(NH₂-MIL-125) were synthesized first, then a series of novel self-standing composite forward osmosis membranes were prepared using NH₂-MIL-125 as filler and POD-COOH as matrix by solution blending and casting method. Further the effects of NH₂-MIL-125 introduction on the structure and performance of composite forward osmosis membranes were investigated. The results demonstrated that the prepared self-standing composite forward osmosis membranes had a dense homogeneous structure. The hydrophilicity and electronegativity of the membranes were improved with increasing NH₂-MIL-125 content. And the composite membranes maintained good mechanical properties. When the testing feed and draw solutions were pure water and 1.5 mol/L Na₂SO₄ solution respectively, the prepared self-standing composite membranes exhibited excellent forward osmosis performance, which is attributed to the elimination of internal concentration polarization existing in support layer of traditional forward osmosis membranes.