复合剥离改性型纳米蒙脱土反渗透膜的抗结垢性能研究  

Study on Anti-scaling Performance of Reverse Osmosis Membrane of Composite Exfoliated and Modified Nano-montmorillonite

作　　者：孟晓婷 刘青松 惠海青 田苗[1] MENG Xiao-ting;LIU Qing-song;HUI Hai-qing;TIAN Miao(School of Ecology and Environment,Northwestern Polytechnical University,Xi'an 710129,China)

机构地区：[1]西北工业大学生态环境学院,西安710129

出　　处：《离子交换与吸附》2024年第4期304-311,共8页Ion Exchange and Adsorption

基　　金：国家自然科学基金(基金号5200105).

摘　　要：反渗透膜的高操作压力、高盐截留率及浓差极化现象,极易导致膜表面形成硫酸钙水垢,造成水渗透性能降低、运营成本升高等问题。膜表面性质是影响结垢的重要因素。纳米材料因具有优异的亲水性能、丰富的特定离子通道,广泛用于提升聚酰胺(PA)层的水渗透性和优化表面特性。文章通过复合剥离改性型纳米蒙脱土(MMT)对膜表面粗糙度、亲水性、表面电荷等进行改性。结果显示,SDS-MMT膜表现出最优的抗结垢性能,与对照组相比,其显示出较低的通量衰减率(DF=27.1%±6.2%)和较高的通量恢复率(F_(R)=94.6%±9.3%)。这是因为MMT和表面活性剂SDS的存在,使PA膜表面亲水性提高,交联密度增大,相应的—COOH含量减少,有利于抑制Ca2+的富集和结垢。文章为膜分离中抗结垢膜的研究提供了新思路。The high operating pressure,high salt rejection ratio and concentration polarization in the reverse osmosis process make it easy to form calcium sulfate scale on the reverse osmosis membrane surface,resulting in reduced water permeability and high operating costs.In addition to process control,the nature of membrane surfaces are crucial to control membrane fouling.Nanomaterials have been extensively used to improve water permeability and optimize the surface properties of polyamide(PA)layers contributed by their excellent hydrophilic properties and abundant specific ion channels.In this study,the surface roughness,hydrophilicity and surface charge of the PA membrane were modified by the incorporation of exfoliated and modified nano-montmorillonite.As compared to the control membrane,the SDS-MMT membrane exhibited the best anti-scaling properties and lower flux decline ratio(Dr=27.1%±6.2%)and higher flux recovery ratio(F_(R)=94.6%±9.3%).It can be concluded that the presence of montmorillonite and surfactant SDS improves the hydrophilicity and cross-linking degree of the PA membrane surface,and the decrease of corresponding-COOH content,which is conducive to anti-scaling.This study also sheds new light on the research of anti-scaling membranes in membrane separation.

关 键 词：纳米蒙脱土 反渗透膜 抗结垢 

分 类 号：X703[环境科学与工程—环境工程]