Lomonosov Moscow State University, Faculty of Geology, Department of Engineering and Ecological Geology, 119991, Leninskiye Gory, 1-1, Moscow, Russia.
Lomonosov Moscow State University, Faculty of Geology, Department of Engineering and Ecological Geology, 119991, Leninskiye Gory, 1-1, Moscow, Russia.
J Hazard Mater. 2018 Sep 15;358:165-170. doi: 10.1016/j.jhazmat.2018.06.023. Epub 2018 Jun 23.
Coupled electrokinetic protective reactive barriers (PRB) are considered as a perspective technology for the treatment of contaminated groundwater. Design of PRB is directly connected with a problem of barrier material choice. Clays can be considered as an appropriate material due to high adsorptive properties and relative cheapness. The barrier internals are formed by clay surface charge properties. We revealed that acidic and alkaline treatment of clay is an effective way to affect its protective properties so that clay can be used to treat various pollutants. Surface charge and electrokinetic properties of clays were characterized by point of zero charge (p.z.c.), point of zero net proton charge (p.z.n.p.c.) and ζ-potential at different pH. Suspensions of 3 main clay types were studied by microelectrophoresis and potentiometric titration methods. At pH > p.z.n.p.c. clayey barrier adsorbs predominantly cationic toxicants and at pH < p.z.c. - anionic ones. The barrier is seemed to be the least effective in pH range between p.z.c. and p.z.n.p.c. Given the physicochemical and electrokinetic parameters, the most efficient clays for barrier design are Cambrian illite and all montmorillonite clays.
耦合电动防护反应屏障（PRB）被认为是一种有前途的处理污染地下水的技术。PRB 的设计直接与屏障材料选择的问题有关。粘土由于具有高吸附性能和相对便宜的价格，可以被认为是一种合适的材料。屏障的内部由粘土表面电荷特性形成。我们发现，酸碱性处理粘土是一种有效的影响其保护性能的方法，因此粘土可以用于处理各种污染物。通过零电荷点（p.z.c.）、零净质子电荷点（p.z.n.p.c.）和不同 pH 值下的 ζ 电位，对粘土的表面电荷和电动特性进行了表征。通过微电泳和电位滴定法研究了 3 种主要粘土类型的悬浮液。在 pH > p.z.n.p.c.时，粘土屏障主要吸附阳离子毒性物质，而在 pH < p.z.c.时，则吸附阴离子毒性物质。在 p.z.c.和 p.z.n.p.c.之间的 pH 范围内，屏障的效果似乎最差。考虑到物理化学和电动参数，对于屏障设计最有效的粘土是寒武纪伊利石和所有蒙脱石粘土。
