聚芳酰胺纳滤膜可控制备及其对染料废水分离性能研究

Controllable preparation of poly(p-phenylene terephthamide)nanofiltration membrane and its separation performance of dye wastewater

随着纳滤膜应用领域的不断扩大,多孔基膜的性能和表面聚酰胺层的结构成为影响纳滤膜分离性能的关键因素。与传统多孔基膜相比,聚对苯二甲酰对苯二胺(PPTA)多孔基膜是一种新型高性能聚芳酰胺材料,具有优异的亲水性、热稳定性和耐酸碱性,是一种理想的膜材料。本研究通过在水相单体溶液中添加金属有机框架UiO-66-NH_(2)颗粒,研究UiO-66-NH_(2)的添加量在界面聚合过程中对PPTA多孔基膜表面聚酰胺层结构的影响,并探究所得表面结构对染料废水渗透/分离性能的影响。实验结果表明,当水相单体溶液中加入1.3g/L UiO-66-NH_(2)时,所得PPTA杂化复合纳滤膜表面呈现纳米条纹状结构。将其用于亚甲基蓝(MB)染料/无机盐分离,与未添加UiO-66-NH_(2)的纯PPTA纳滤膜相比,PPTA杂化复合纳滤膜对MB截留率高达98.2%,渗透通量19.79L/m^(2)·h·MPa,表现出优良的渗透/分离性能。

With the continuous expansion of nanofiltration membrane applications,the properties of the porous base membrane and the structure of the surface polyamide layer have become key factors affecting the separation performance of the nanofiltration membrane.Compared with traditional porous membranes,poly(p-phenylene terephthamide)(PPTA)porous membranes are a new type of high-performance aromatic polyamide materials with excellent hydrophilicity,thermal stability,acid and alkali resistance,making it an ideal membrane material.In this study,PPTA/UiO-66-NH_(2)(PPUM)nanofiltration membranes were prepared by adding metal-organic framework UiO-66-NH_(2)particles to the aqueous-phase monomer solution combined with the interfacial polymerization method,and the effect of the addition of UiO-66-NH_(2)on the structure of the polyamide layer on PPUM nanofiltration membraneswere investigated,and the influence of the PA surface structure on the permeation/separation performance of the dye wastewater was further explored.The experimental results showed that when the concentration of 1.3g/L UiO-66-NH_(2)was added to the aqueous phase solution,the surface of the obtained PPTA hybrid composite nanofiltration membrane showed a nano-striped structure.Compared with pure PPTA nanofiltration membranes without UiO-66-NH_(2),PPTA hybrid composite nanofiltration membranes had a rejection rate of up to 98.2%and permeability flux of 19.79L/m^(2)·h·MPa,showing excellent permeation/separation performance compared with pure PPTA nanofiltration membranes without UiO-66-NH_(2).