Development of Functional Porous Membrane Prepared by Radiation-Induced

通过选择接枝聚合和化学改性的溶剂，在聚乙烯微滤膜上引入高密度的亚氨基二乙酸酯（IDA）基团，同时不降低膜的水通量。甲基丙烯酸缩水甘油酯（GMA）在甲醇溶剂中接枝到多孔中空纤维上增强了基质的溶胀，从而补偿了孔体积的减小。随后，二甲基亚砜（DMSO）/水溶剂提供了所产生的环氧基团向IDA基团的更高转化率。所得含IDA基团的中空纤维具有足够的钴结合能力，并将水通量保持在可行的水平。GMA接枝率为197%的螯合中空纤维的通量保持在约70%，即，2.0m^3/（m^2h）。中空纤维的钴饱和容量为1.9mol/kg。当含钴溶液通过中空纤维的微孔渗透时，钴离子在中空纤维上有一个尖锐的穿透曲线。随后，将产生的环氧基团转化为亚氨基二乙酸酯（IDA）基团。钴溶液通过亚微米直径的孔渗透穿过螯合多孔膜。渗透过程中钴离子的有效去除由所得的穿透曲线证明。此外，通过X-射线微分析（XMA）确定作为流出物体积的函数的跨膜吸附的钴的量的分布。穿透曲线的形状是不依赖于液体停留时间，和XMA线轮廓的定期传播相当于吸附的钴表明，总的吸附速率是不受钴离子的IDA组的螯合多孔膜的扩散阻力。

A method by which to introduce a high-density iminodiacetate (IDA) group into a polyethylene microfiltration membrane without lowering the water flux was developed by selecting the solvents for graft polymerization and subsequent chemical modification. Grafting of glycidyl methacrylate (GMA) onto the porous hollow fiber in a methanol solvent enhanced the swelling of the matrix and thus compensated for the decrease in pore volume. Subsequently, the dimethyl sulfoxide (DMSO)/water solvent provided a higher conversion of the produced epoxide group into the IDA group. The resulting IDA-group-containing hollow fiber had a sufficient cobalt-binding capacity and maintained the water flux at a feasible level. The flux of the chelating hollow fiber, whose degree of GMA grafting was 197%, was kept at about 70%,i.e.,2.0m^3/(m^2h) of that of the starting hollow fiber. The cobalt saturation capacity of the hollow fiber was 1.9mol/kg. When a cobalt-containing solution permeated across the chelating hollow fiber through its pores, a sharp breakthrough curve of the cobalt ion was observed.Glycidyl methacrylate was grafted onto a microfiltration hollow-fiber membrane. Subsequently, the produced epoxide group was converted into an iminodiacetate (IDA) group. The cobalt solution was permeated across the chelating porous membrane through the submicron-diameter pores. The efficient removal of cobalt ion during permeation was demonstrated by the resulting breakthrough curve. Furthermore, the profile of the amount of cobalt sorbed across the membrane was determined as a function of the effluent volume by X-ray microanalysis (XMA). The shape of the breakthrough curves was not dependent on the liquid residence time, and the regular propagation of the XMA line profile equivalent to that of sorbed cobalt demonstrated that the overall sorption rate was not governed by the diffusional resistance of cobalt ion to the IDA group of the chelating porous membrane.