Water scarcity is an increasing problem around the world due to growing population and more frequent weather extremities. Desalination, the process in which salt water is converted into freshwater, is a sensible option to expand the drinking water supply by accessing the vast sal
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Water scarcity is an increasing problem around the world due to growing population and more frequent weather extremities. Desalination, the process in which salt water is converted into freshwater, is a sensible option to expand the drinking water supply by accessing the vast salt water resources on Earth. Capacitive deionization (CDI) is a novel desalination technology that is based on separating salt ions from aqueous solutions in an electrical double layer. An electrostatic potential difference is applied between two high surface area electrodes, the two oppositely charged electrodes attract and adsorb salt ions onto the electrode surface, as such producing a purified stream of water. In time, the electrodes become saturated with ions. To regenerate the electrodes the applied potential is removed or reversed, producing a concentrated stream of water. For brackish water, this new fundamental method of desalination has advantages over conventional desalination technologies. CDI can be operated with minimal energy requirement in ambient pressures and temperatures, delivering easy operable systems. This thesis investigates manufacturing of activated carbon electrodes purposed for multi-channel CDI. Current CDI systems operate by desalinating one channel and concentrating the same channel periodically. Multi-channel CDI operates a charging scheme, utilizing more than two electrodes, to desalinate one channel into another channel, circumventing the need to separate desalinated water from concentrated water downstream. Due to the different mode of separation are currently available CDI electrodes not tailored to, or not usable at all, in multi-channel CDI.In this project six successful different types of electrodes have been manufactured by dip coating. The coating compositions applied are 80:10:10, 70:10:20 and 40:40:20 using activated carbon powder (ACP), carbon black and PVDF binder respectively. The in-house build electrodes are analyzed with cyclic voltammetry, desalination measurements and a surface and pore size analyzer. Two-dimensional electrosorption simulations are performed to explore the effect of electrode resistance, micropore porosity and electrode thickness. The dip coated electrodes resulted in permeable smooth uniform electrodes. The electrodes with the most amount of ACP displayed largest capacitance and salt adsorption capacity. Electrosorption modelling shows that thin, highly electrical conductive electrodes are desired in multi-channel CDI operation.