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In this work, we investigated the feasibility of ammonium removal by electrodialysis (ED), a well‐known electro‐membrane process, based on the selective migration of anions and cations through anion exchange membranes (AEMs) and cation exchange membranes (CEMs). ED experiments are performed using a laboratory pilot. The ion exchange membranes (IEMs) pair used is AXE/CMX, AXE as an AEMs and CMX as a CEMs. The first tests are performed with real groundwater solutions from Kenitra city (Morocco), spiked with an initial concentration of 3 mg/L NH4Cl. The results gave a specific demineralization (SD) to NH4+ ions of 84.60 %; for a demineralization rate (DR) of 80 % and a time of 60 min. The multivariate principal component analysis (PCA) presents a total inertia of 99.23 %, the majority of the variables of which are positively correlated on the C1 axis with a variance of 95.5 % than that of C2 of 3.78 %. The quality of the diluted water determined by the Legrand‐Poirier method showed that the water was aggressive and that the addition of 4.54 mg/L Ca2+ was necessary to balance the water and make it fit for human consumption. [ABSTRACT FROM AUTHOR]

Water hardness significantly impacts water quality, influencing both industrial processes and daily domestic applications. This study investigates the efficacy of electrodialysis (ED) in removing hardness, aiming for a balanced approach that avoids aggressive or scaling tendencies. Response surface methodology (RSM) was employed to determine the interaction between the inputs and the hardness removal, optimizing key parameters using the Box-Behnken design (BBD). The resulting regression model, validated through analysis of variance (ANOVA), demonstrated a high R² value of 0.9761 and an adjusted R² value of 0.9454, indicating a robust fitness for hardness removal prediction. The interaction of both voltage and initial concentration holds significance in our investigative study. A notable hardness removal efficiency of 87% was achieved at a demineralization time of 47 min, an applied voltage of 11V and an initial concentration of 5.3 mmol/L. This research enhances our understanding of critical operating parameters in ED, offering insights for optimizing the process toward effective water softening and long-term water treatment. [ABSTRACT FROM AUTHOR]

The manufacture of the handcrafted items is carried out in a succession of deposit baths and rinses. However, this process gives rise to complex and highly loaded effluents, including a mixture of heavy metals (Cu(II), Ag(I) and Ni(II)). Therefore, to meet the Moroccan discharge limits, it is necessary to treat these effluents before discharging them into the natural environment. The objective of this study is the comparison of electrodialysis (ED) and reverse osmosis (RO) in the reduction of heavy metals in brassware wastewater of the city of Fez (Morocco). The first part is devoted to the study of the influence of the operating parameters of RO (transmembrane pressure (TMP) and recovery rate) on the quality of the permeate. The rejection (R) of metal ions (Cu(II), Ag(I) and Ni(II)) increases with TMP, but decreases with the increase in the recovery rate. The maximum values of 96%, 66.39% and 99.6% have been reached for Cu(II), Ag(I) and Ni(II), respectively. The second part of this work focuses on the feasibility of ED in the removal of heavy metals. The influence of the demineralization rate (DR) on the quality of the dilute is studied. Results show that the removal rate of cations (Cu(II), Ag(I) and Ni(II)) increases with the increase of DR and reaches, respectively 98%, 95% and 97% for a DR of 90%. Finally, a comparison between RO and ED based on the water quality delivered and the energy consumed is performed under optimal operating conditions. [ABSTRACT FROM AUTHOR]

The surface treatment workshops (brassware) are among the artisanal specialties of the city of Fez, which generate toxic and harmful effluents. In fact, the large amount of produced effluents is rich in heavy metals. Hence it is necessary to treat these effluents before returning them to the natural environment or for reuse. In the brassware workshops, the production of craft items passes through a chain of surface treatment and rinsing baths. Various rinsing baths are used: degreasing baths, alkaline copper-plating baths, acid copper-plating baths, nickel-plating baths and silver-plating baths. These rinsing baths are loaded with heavy metals (copper, silver and nickel). In order to treat these effluents to comply with the discharge limit values, the Ministry of Tourism, Crafts of Air Transport and Social Economy and Ibn Tofail University have agreed to launch a research collaboration to study the feasibility of membrane-based processes -- electrodialysis (ED), nanofiltration and reverse osmosis -- in the treatment of these effluents. This first study aims to investigate the removal of heavy metals from rinsing baths by ED. Two couples of ion-exchange membranes have been tested ACS/CMX and AXE/CMX. Using the selected couple of ion-exchange membranes (CMX/AXE), the treatment by ED of mixing of all rinsing baths, brassware wastewater loaded with copper, silver, nickel is performed. Removal of 98%, 95%, 97% of copper, nickel and silver are respectively achieved. [ABSTRACT FROM AUTHOR]