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    陈硕

    • 教授   博士生导师   硕士生导师
    • 主要任职:无
    • 性别:女
    • 毕业院校:大连理工大学
    • 学位:博士
    • 在职信息:在职
    • 所在单位:环境学院
    • 学科:环境工程 环境科学
    • 办公地点:大连理工大学环境学院B717
    • 联系方式:0411-84706263
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    Improving Ion Rejection of Conductive Nanofiltration Membrane through Electrically Enhanced Surface Charge Density

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    论文类型:期刊论文

    第一作者:Zhang, Haiguang

    通讯作者:Quan, X (reprint author), Dalian Univ Technol, Minist Educ, Sch Environm Sci & Technol, Key Lab Ind Ecol & Environm Engn, Dalian 116024, Peoples R China.

    合写作者:Quan, Xie,Fan, Xinfei,Yi, Gang,Chen, Shuo,Yu, Hongtao,Chen, Yongsheng

    发表时间:2019-01-15

    发表刊物:ENVIRONMENTAL SCIENCE & TECHNOLOGY

    收录刊物:SCIE、Scopus

    卷号:53

    期号:2

    页面范围:868-877

    ISSN号:0013-936X

    关键字:Charge density; Desalination; Ions; Microfiltration; Nanofiltration; Nanofiltration membranes; Sodium chloride; Sodium sulfate; Surface charge; Water treatment, Bulk solutions; Donnan potential; Enhanced surface charge; External voltages; High permeability; Monovalent ions; Rejection rates; Seawater desalination, Sulfur compounds

    摘要:Nanofiltration (NF) is considered a promising candidate for brackish and seawater desalination. NF exhibits high multivalent ion rejection, but the rejection rate for monovalent ions is relatively low. Besides, great challenges remain for conventional NF membranes to achieve high ion rejection without sacrificing water flux. This work presents an effective strategy for improving the ion rejection of conductive NF membrane without decreasing the permeability through electrically assisted enhancement of surface charge density. When external voltage is increased from 0 to 2.5 V, the surface charge density of the membrane increases from 11.9 to 73.0 mC m(-2), which is 6.1X higher than that without external voltage. Correspondingly, the rejection rate for Na2SO4 increases from 81.6 to 93.0% and that for NaCl improves from 53.9 to 82.4%; meanwhile, the membrane retains high permeabilities of 14.0 L m(-2) h(-1) bar(-1) for Na2SO4 filtration and 14.5 L m(-2) h(-1) bar(-1) for NaCl filtration. The Donnan steric pore model analysis suggests that the Donnan potential difference between the membrane and bulk solution is increased under electrical assistance, leading to increased ion transfer resistance for improved ion rejection. This work provides new insight into the development of advanced NF technologies for desalination and water treatment.