基于新型二胺单体的反渗透膜的制备及其脱盐性能研究

Novel reverse osmosis membrane based on a new diamine monomer:Fabrication and desalination performance

研究合成了一种新型磺化二胺单体4,4′-{[1,4-亚苯基双(亚甲基)]二氨基}二苯磺酸(PMABSA),并将其作为唯一的水相单体替代传统的间苯二胺(MPD)与均苯三甲酰氯(TMC)来制备新型磺化聚酰胺复合反渗透膜.采用响应面法对PMABSA/TMC膜的分离性能进行优化,最优膜的纯水渗透系数达(11.8±0.3) L/(m^2·h·MPa),对NaCl的截留率高达98.2%±0.4%.在模拟海水脱盐实验中,PMABSA/TMC膜对所有离子的去除率都略优于商业膜SW30HR(陶氏),且在中性条件下对硼元素的截留率高达91.1%,体现出极佳的海水淡化应用前景.

A new sulfonated diamine monomer, 4,4′-[1,4-phenylenebis(methylene) bis(azanediyl)] dibenzenesulfonic acid(PMABSA) was synthesized and used as the sole aqueous reactant to fabricate a novel reverse osmosis(RO) membrane with trimesoyl chloride(TMC), in place of conventional m-phenylene diamine(MPD). The separation performance of the PMABSA/TMC membrane was optimized by the response surface method(RSM) by means of evaluating the pure water permeability(PWP) and salt rejection(R) to NaCl, and optimal results of PWP of(11.8±0.3) L/(m^2·h·MPa), and R of 98.2%±0.4%, respectively, were achieved at 1.55 MPa. The PMABSA/TMC membrane exhibited a superior rejection ability to all the ions compared to that of commercial SW30 HR(Dow Chemical) in a model seawater separating test. It is worth noting that the boron removal rate of the RO membrane under the neutral condition was as high as 91.1%. Overall, all the results reaevled the great potential of the novel membrane as a new choice of non-MPD RO membrane for seawater desalination.