Breida M, Alami Younssi S, Bouazizi A, Achiou B, Ouammou M, El Rhazi M
Laboratory of Materials, Membranes and Environment, Department of Chemistry, Faculty of Sciences and Technologies of Mohammedia, University Hassan II of Casablanca, BP 146, Mohammedia 20650, Morocco.
Heliyon. 2018 Jan 18;4(1):e00498. doi: 10.1016/j.heliyon.2017.e00498. eCollection 2018 Jan.
In the framework of understanding the transport mechanism that governs the filtration of NO solution through a -AlO membrane with a nominal pore size of 5 nm at low ultrafiltration, a series of various types of nitrate solutions and operating conditions were investigated. The effect of filtration parameters such as pH, applied pressure and NO concentration on the selectivity and permeability of the membrane were studied using binary solutions (KNO, NaNO, Ca(NO) and Mg(NO)) and ternary solutions ((NaNO + KNO), (NaNO + Ca(NO)) and (Mg(NO) + Ca(NO)). The experimental filtration results showed that high NO rejection was observed when pH was close to the point of zero charge of the membrane for both binary and ternary solutions. NO rejection increased with an increase of applied pressure. The rejection gradually decreased when the initial NO concentration increased. It appeared that the valency and hydrated radius of associated cation had a dramatic effect on NO rejection, with the divalent cations being more rejected than monovalent cations. In order to get to natural water complexity, three different samples of mineral water doped with NO from two different sources were studied at optimized operating conditions (25 ppm of NO and 6 bar). Experimental results demonstrated that NO rejection strongly depended upon the total mineralization and the presence of divalent anions in solution. In addition, the obtained results showed the potential use of -AlO ultrafiltration membrane for denitrificatoin of contaminated water especially in Moroccan agricultural areas.
在理解低超滤条件下通过标称孔径为5 nm的α -AlO膜过滤NO溶液的传输机制的框架内，研究了一系列不同类型的硝酸盐溶液和操作条件。使用二元溶液（KNO、NaNO、Ca(NO) 和Mg(NO)）以及三元溶液（(NaNO + KNO)、(NaNO + Ca(NO)) 和 (Mg(NO) + Ca(NO))）研究了诸如pH值、施加压力和NO浓度等过滤参数对膜的选择性和渗透性的影响。实验过滤结果表明，对于二元和三元溶液，当pH值接近膜的零电荷点时，观察到较高的NO截留率。NO截留率随施加压力的增加而增加。当初始NO浓度增加时，截留率逐渐降低。似乎相关阳离子的价态和水合半径对NO截留率有显著影响，二价阳离子比一价阳离子更易被截留。为了接近天然水的复杂性，在优化的操作条件（25 ppm的NO和6 bar）下研究了来自两个不同来源的掺有NO的三种不同矿泉水样品。实验结果表明，NO截留率强烈依赖于总矿化度和溶液中二价阴离子的存在。此外，所得结果表明α -AlO超滤膜在处理受污染水的反硝化方面具有潜在用途，特别是在摩洛哥农业地区。
