| dc.description.abstract | Capacitive deionization (CDI) is an emerging seawater desalination technology. By applying a voltage, ions in the water are adsorbed onto the electrode material. It has the advantages of simple operation, no secondary pollution, and low operating cost. In this reserch, capacitive deionization was used to remove ammonium ions in water, and activated carbon was dripped onto a titanium plate as an electrode. Experiments were conducted with ammonium chloride solution and ammonium fluoride solution, and different voltages were used to explore the ability of activated carbon to adsorb
ammonium ions and discusses the changes in the species of ammonium. In addition, this reserch fitted the kinetics, and the results showed that the Elovich model is the most consistent, with R2 almost higher than 0.95. This model
represents the change of chemical bonds involved in the capacitive adsorption process. After 8 hours of voltage application, it can be seen that the pH was increased compared to the initial pH, which may be caused by hydroxide ions generated by hydrolysis. Besides, NO3− was detected in all conditions, NO2− was detected in a few conditions and NH3 and N2 were presumed to be produced. The removal amount of ammonium in 1.5 mM NH4F is ten times higher than in 1.5 mM NH4Cl at 1.2 V. Besides, the production of NO3− in NH4F is about 33 times that in NH4Cl at 1.2 V. | en_US |