γ-Al_2O_3纳米孔膜截留镁离子机理的研究  

Investigation of the Magnesium Ion Retention Mechanism of γ-Al_2O_3 Mesoporous Membranes

作　　者：董国光[1] 李建明[1] 陈志[1] 梁希[1] 郝静[1] 董蓉[1] 黄莹[1] 

机构地区：[1]四川大学化工学院,四川成都610065

出　　处：《过滤与分离》2008年第1期15-17,共3页Journal of Filtration & Separation

摘　　要：纳米孔膜的过滤类似于反渗透和超滤,均属于压力驱动的膜过程,但其传质机理却有所不同。根据实验数据用作图的方法得出膜的真实截留率,进而求出膜面浓度。通过实验发现,细孔模型中对特征参数σ和ω的计算与实验值有一定的出入,主要是由于在细孔模型中只考虑了结构尺寸对截留率的影响,而在道南效应决定膜对盐的截留性能的情况下,截留性能主要依赖于离子和膜之间的静电相互作用,电荷因素不容忽略,因此细孔模型用于描述纳米孔膜的分离机理时,其准确性不高。Mesoporous membrane filtration process is similar to reverse osmosis and ultrafiltration which are both pressure driven processes, but its transport mechanism is quite different from those of the latter. The real retention coefficient is determined by graphical method based on the experimental data, and the concentration at the membrane/feed interface comes accordingly. It is found from the experimental results that the reflection coefficient σ and solute permeability ω are different from those calculated by pore flow model. The main reason might be that the pore flow model assumes that separation of different permeates is achieved by size exclusion. When Donnan effect exists, mutual electrostatic effects between ion and membrane surface influence the separation performance, the electrostatic charge can not be neglected, and the accuracy of pore flow model becomes poor.

关 键 词：γ-AlO3 纳米孔膜 截留 机理 模型 

分 类 号：TQ028.8[化学工程]