Contact glow discharge electrolysis system for treatment of wastewater containing ammonia

Contact glow discharge electrolysis produced many active species such as OH radical, which has important role in degrading complex pollutants. This study utilizes Contact Glow Discharge Electrolysis (CGDE) system to remove ammonia from wastewater. Variables such as electrolyte concentration, voltage and temperature are studied their effects on CGDE's performance. Experimental results show that the hydroxyl radicals produced is higher than the ammonia degraded during the CGDE process. In general, increasing potential discharge will increase electrical current. The highest yield of hydroxyl radicals was obtained at a depth of anode 5 mm although the anode surface area more submerged than CDGE. Ammonia degradation efficiency increase with increases in electrolyte concentration, voltage and temperature applied in the CGDE processes. The optimum condition is achieved using KOH 0.02 M at 700 v and 60°C, where at such condition ammonia degradation efficiency and energy consumption are 89.2% and 80 kJ mmole^-1, respectively. These results show that the CGDE process has the potential to be used to degrade wastewater containing ammonia.