Bhattacharjee S, Kim AS, Elimelech M
Department of Chemical Engineering, Yale University, 9 Hillhouse Avenue, New Haven, Connecticut, 06520-8286
J Colloid Interface Sci. 1999 Apr 1;212(1):81-99. doi: 10.1006/jcis.1998.6045.
A theoretical approach for predicting the influence of interparticle interactions on concentration polarization and the ensuing permeate flux decline during cross-flow membrane filtration of charged solute particles is presented. The Ornstein-Zernike integral equation is solved using appropriate closures corresponding to hard-spherical and long-range solute-solute interactions to predict the radial distribution function of the solute particles in a concentrated solution (dispersion). Two properties of the solution, namely the osmotic pressure and the diffusion coefficient, are determined on the basis of the radial distribution function at different solute concentrations. Incorporation of the concentration dependence of these two properties in the concentration polarization model comprising the convective-diffusion equation and the osmotic-pressure governed permeate flux equation leads to the coupled prediction of the solute concentration profile and the local permeate flux. The approach leads to a direct quantitative incorporation of solute-solute interactions in the framework of a standard theory of concentration polarization. The developed model is used to study the effects of ionic strength and electrostatic potential on the variations of solute diffusivity and osmotic pressure. Finally, the combined influence of these two properties on the permeate flux decline behavior during cross-flow membrane filtration of charged solute particles is predicted. Copyright 1999 Academic Press.
本文提出了一种理论方法，用于预测在带电溶质颗粒错流膜过滤过程中，颗粒间相互作用对浓差极化及随之而来的渗透通量下降的影响。通过使用与硬球和长程溶质 - 溶质相互作用相对应的适当封闭项，求解奥恩斯坦 - 泽尔尼克积分方程，以预测浓溶液（分散体系）中溶质颗粒的径向分布函数。基于不同溶质浓度下的径向分布函数，确定溶液的两个性质，即渗透压和扩散系数。将这两个性质的浓度依赖性纳入由对流扩散方程和渗透压控制的渗透通量方程组成的浓差极化模型中，可实现溶质浓度分布和局部渗透通量的耦合预测。该方法可在标准浓差极化理论框架内直接定量纳入溶质 - 溶质相互作用。所开发的模型用于研究离子强度和静电势对溶质扩散率和渗透压变化的影响。最后，预测了这两个性质对带电溶质颗粒错流膜过滤过程中渗透通量下降行为的综合影响。版权所有1999年学术出版社。
