摘要
采用DK纳滤膜进行电解质KCl-MgCl2水溶液纳滤实验,考察pH、盐浓度及类型对纳滤膜性能的影响。通过道南细孔-介电(DSPM-DE)模型计算等效荷电密度(X d),研究DK纳滤膜表面电荷与性能之间的关系。通过DSPM模型拟合不同pH条件下葡萄糖截留数据表征膜的结构性质。结果表明:膜的等效膜孔(r p)和等效膜厚(!x/A k)数值在碱性条件下大于酸性及中性的;KCl的截留率随盐浓度增加而减小,pH为4.0时截留率最小;MgCl2的截留率随盐浓度增加而增大,随pH增大而减小。模型分析发现X d取决于pH、盐浓度及类型;对KCl和MgCl22种溶液,膜性能取决于所对应条件下X d的大小。
Single salt solutions KC1-MgCI2 were filtrated with a commercially available DK nanofihration membrane to evaluate effects of pH, as well as concentration and type of salt in the feed side on the mem- brane performance. The Donnan steric pore and dielectric exclusion（DSPM-DE） model was used to calcu- late effective membrane charge density, and the relationship between the membrane surface charge and the performance was analyzed. Membrane characterization was completed by introducing structural properties, by the fit of the DSPM model on real glucose rejections at different pH. Results revealed that higher values of rp and Ax/Ak were observed in the alkaline region compared with that of the neutral or acidic region. KC1 rejection always decreased with the increased salt concentration and the minimum rejection at pH 4.0 was obtained in contrast, MgC12 rejection increased with the increased salt concentration and the decreased pH. Model analysis showed that Xd was affected by pH, concentration and type of salt in the feed side, and what was important in determining the membrane performance was the role of Xd existing under the corresponding conditions.
出处
《南京工业大学学报（自然科学版）》
CAS
北大核心
2013年第6期43-47,共5页
Journal of Nanjing Tech University(Natural Science Edition)
基金
江苏省科技厅产学研前瞻性联合研究项目(BY2009106)
国家自然科学基金(20576052)
关键词
纳滤
膜性能
PH
盐
等效荷电密度
aanofiltration
membrane performance
pH
salt
effective charge density
