Optimization of electrodialysis metathesis (EDM) desalination using factorial design methodology

Abstract

A complete set of experimental data on novel Electrodialysis Metathesis (EDM) desalination was analyzed using factorial design. EDM consists of repeating quads of four ion-exchange membranes and solution compartments to allow double decomposition reaction between the cations and anions of a feed and a substitution solution when current is applied between the electrodes. The effect of factors affecting the EDM desalination efficiency, such as voltage, flow rate, membrane type, and feed water source was studied using a full 2 4 factorial experimental design. The General Linear Model was used to evaluate the combined effect of the discrete and continuous factor variables introduced in the design. It was found that voltage, water source and membrane type were the most influential factors on the EDM process. Interaction terms were found to be insignificant. The effect of main factors on EDM desalination follow the order voltage > water source > type of membrane. EDM desalinate well saline waters with TDS concentrations higher that the TDS of surface water by applying 15 volts and using Neosepta membranes. The responses obtained with the GLM were in agreement with the experimental data, thus confirming the ability of the model to predict desalination results. Complete desalination of high salinity water was achieved without formation of precipitates in the stack due to the ability of EDM to convert sparingly soluble salts into highly soluble salts.

Electrodialytic Processes: Market Overview, Membrane Phenomena, Recent Developments and Sustainable Strategies

“…In order to reach optimum conditions in terms of highest current efficiency and product purity, researchers have been continuously studying process parameters. Hence, it was reported that high voltage difference across the stack, sufficiently high feed concentration, equimolar ratio of reactant salts, high membrane transport number and moderate flow rate are critical parameters to obtain ideal operating conditions [ 144 , 145 , 146 , 147 , 148 , 149 ]. The difference in concentration across the membrane is also of particular importance, since it may result in co-ion fluxes leading to impurities in the final product; monovalent cations are especially subject to this phenomenon [ 150 ].…”

Facile synthesis of TiO2/ZrO2 nanofibers/nitrogen co-doped activated carbon to enhance the desalination and bacterial inactivation via capacitive deionization

“…Recently, water has presented a major dilemma for the sustainable development of many regions and work industries since increasing socio-economic development has brought ever more stringent conflicts between the growing demand for fresh water and reduction in supply, in addition to the high proportions of biocontamination. The most straightforward solution to improve the quantity, as well as the quality of water, is desalination of salty water source like sea or brackish water, based on the generality of Earth’s water being saline 3 . Several conventional desalination methodologies have been carried out to improve the supply of fresh water, the most common of which are reverse osmosis (RO), electrodialysis and thermal distillation 4 , 5 .…”

Evaluation of the feasibility of short‐term electrodialysis for separating naturally occurring fluoride from instant brick tea infusion

“…The results suggest that by increasing the applied voltage from 5 to 20 V in the ED stack the rate of defluoridation is increased. The rate increases possibly because more driving force was provided to drive fluoride ion transport across the anion membrane when the voltage was high . However, the defluoridation rate within 4 min of ED did not increase at a voltage of 30 V ( P > 0.05).…”