摘要
以N,N-二甲基乙酰胺为溶剂,磺化聚砜/聚砜/聚乙烯吡咯烷酮为溶质配制铸膜液,采用非溶剂诱导相转化法制备基膜,然后以均哌嗪为水相单体,均苯三甲酰氯为油相单体制备聚酰胺皮层,得到复合膜。通过扫描电镜(SEM)、电化学阻抗谱(EIS)等研究了不同组分对于复合膜的形态结构、化学组成等方面的影响。通过电渗析试验(ED)研究了复合膜的性能对于一价和二价阳离子的分离作用。结果表明,铸膜液中聚合物含量影响相分离过程,低聚合物含量会加快相分离过程,易于形成指状大孔隙结构,进而增加膜厚度和离子交换容量,对膜电阻的增大有影响。在相同磺化度下,含10%磺化聚砜的复合膜在100 A/m^(2)电流密度下有较好的二价阳离子选择性,电流密度为200 A/m^(2)时离子通量上升而选择性下降。升高电流密度会降低复合膜对于二价阳离子的选择性。
Using N,N-dimethylacetamide as the solvent and sulfonated polysulfone/polysulfone/polyvinyl-pyrrolidone as solutes,a casting solution was prepared.The base membrane was fabricated via non-solvent induced phase inversion,and a polyamide selective layer was subsequently formed on top using piperazine as the aqueous phase monomer and trimesoyl chloride as the organic phase monomer,resulting in a composite membrane.The effects of different components on the morphological structure and chemical composition of the composite membrane were investigated using scanning electron microscopy(SEM)and electrochemical impedance spectroscopy(EIS).The performance of the composite membrane in separating mono-and divalent cations was studied through electrodialysis(ED)experiments.The results showed that the polymer content in the casting solution influences the phase separation process.A low polymer content accelerates phase separation,facilitating the formation of a finger-like macroporous structure,which increases membrane thickness and ion exchange capacity,thereby contributing to higher membrane resistance.At the same degree of sulfonation,the composite membrane with 10%sulfonated polysulfone content exhibited the good selectivity for divalent cations at a current density of 100 A/m^(2).When the current density increased to 200 A/m^(2),the ion flux increased while selectivity decreased.Increasing the current density reduces the selectivity of the composite membrane for divalent cations.
作者
刘国梁
张杨
LIU Guoliang;ZHANG Yang(College of Environment and Safety Engineering,Qingdao University of Science and Technology,Qingdao 266042,China)
出处
《工业用水与废水》
2025年第6期67-75,共9页
Industrial Water & Wastewater
基金
国家重点研发计划(2022YFB3805104)。
关键词
复合离子膜
电渗析
选择透过性
相转化
磺化聚砜
composite ion membrane
electrodialysis
selective permeability
phase inversion
sulfonated polysulfone
