二乙基聚氯乙烯基膦酸酯的合成及其对Li^(+)的电驱动传质

Synthesis of Diethyl Polyvinyl Chloride Phosphonate and Its Electrodriven Mass Transfer to Li^(+)

传统聚合物包容膜(PIM)由于载体与膜基质间非键合,传质速率与稳定性有待提高。为了同时兼顾这两点,将聚氯乙烯(PVC)与亚磷酸三乙酯(TEPi)通过Arbuzov反应制备二乙基聚氯乙烯基膦酸酯(PVCTPE),加入协萃剂二(2-乙基己基)磷酸酯(D2EHPA)与塑化剂邻苯二甲酸二辛酯(DOP)制备了PVC膦酸酯化的聚合物膜材料PVCTPEDD,探究了不同条件对PVCTPEDD电驱动传质Li^(+)的影响,评价了体系的传质性能。结果表明,当电压为20 V时,在PVCTPE质量分数为56.2%,D2EHPA质量分数为31.3%,DOP质量分数为12.5%的最佳配比下,PVCTPEDD对Li^(+)渗透系数为9.60μm/s,对Li^(+)的去除率和回收率均大于90%。电压对PVCTPEDD传质的影响与传统PIM有显著区别,渗透系数、去除率和回收率随电压升高无下降趋势。PVCTPEDD电驱动传质体系在4个周期循环的传质中,其渗透系数与末端电流无明显变化,具有较高的稳定性。高稳定性的PVCTPEDD有望突破传统PIM的传质速率困境从而得到工业化应用。

Due to the non-bonding between the carrier and the membrane matrix in the traditional polymer inclusion membrane(PIM),the mass transfer rate and stability need to be improved.In order to take into account these two points at the same time,diethyl polyvinyl chloride phosphonate(PVCTPE)was prepared by Arbuzov reaction with polyvinyl chloride(PVC)and triethyl phosphite(TEPi),and the PVC phosphonic acid esterified polymer membrane material PVCT_(PE)DD was prepared by adding coextractant bis(2-ethylhexyl)phosphate(D2EHPA)and plasticizer dioctyl phthalate(DOP),and the effects of different conditions on the electrodriven mass transfer Li+by PVCT_(PE)DD were investigated.The mass transfer performance of the system was evaluated.The results show that at the optimum composition of 56.2 wt%PVCTPE+31.3 wt%D2EHPA+12.5 wt%DOP and a voltage of 20 V,the permeability coefficient of PVCT_(PE)DD to Li^(+)is 9.60μm/s,and the removal and recovery rate of Li^(+)are greater than 90%.The effect of voltage on mass transfer is significantly different from traditional PIM,with no decreasing trend of permeation coefficient,removal rate and recovery rate with increasing voltage.The permeability coefficient and terminal current of PVCT_(PE)DD electrodriven mass transfer system have no obvious changes in four cycles,which has high stability.PVCT_(PE)DD with high stability is expected to break through the mass transfer rate dilemma of traditional PIM and thus be applied industrially.