Nitrate removal from aqueous solutions by γ-Al2O3 ultrafiltration membranes. Issue 1 (January 2018)

• Record Type: Journal Article
• Authors: Breida, M.; Alami Younssi, S.; Bouazizi, A.; Achiou, B.; Ouammou, M.; El Rhazi, M.
• Is Part Of: Heliyon. Volume 4:Issue 1(2018)
• Publication Date: 2018-01
• Subjects: Environmental science -- Chemical engineering -- Materials science -- Chemistry; Research -- Periodicals; Medical sciences -- Periodicals; Natural history -- Periodicals; Social sciences -- Periodicals; Earth sciences -- Periodicals; Physical sciences -- Periodicals; 507.2
• DOI: 10.1016/j.heliyon.2017.e00498
• Languages: English
• ISSNs: 2405-8440

Abstract

Abstract: In the framework of understanding the transport mechanism that governs the filtration of NO3 − solution through a γ -Al2 O3 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 NO3 − concentration on the selectivity and permeability of the membrane were studied using binary solutions (KNO3, NaNO3, Ca(NO3 )2 and Mg(NO3 )2 ) and ternary solutions ((NaNO3 + KNO3 ), (NaNO3 + Ca(NO3 )2 ) and (Mg(NO3 )2 + Ca(NO3 )2 ). The experimental filtration results showed that high NO3 − rejection was observed when pH was close to the point of zero charge of the membrane for both binary and ternary solutions. NO3 − rejection increased with an increase of applied pressure. The rejection gradually decreased when the initial NO3 − concentration increased. It appeared that the valency and hydrated radius of associated cation had a dramatic effect on NO3 − 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 NO3 − from two different sources were studied at optimized operating conditions (25 ppm of NO3 − and 6 bar). Experimental results demonstrated that NO3 − 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 γ -Al2 O3 ultrafiltration membrane for denitrificatoin of contaminated water especially in Moroccan agricultural areas.