Electrochemical removal of ammonia and total nitrogen in micro-polluted water using TI/RU electrodes

The micro-polluted water (MPW) from Wenyu River in Beijing area was used for this study. Tests of electrolysis were carried out using an electrolytic device which consisted of a ruthenium-coated titanium anode plate and a steel cathode plate. Plate distance, current density and retention time were the parameters for analyzing the removal efficiency of pollutants from MPW. Surface and electrochemical characteristics of the anode plate were also studied. The results reveal that by increasing the plate distance, current density and retention time, nitrogenous compounds removal efficiency could be improved to a limited extent. For plate distance of 1.5 cm, retention time of 20 min and current density of 260 A/m(2), the highest removal efficiency of nitrogenous compounds was achieved: ammonia and total nitrogen removals were about 95 and 80%, respectively. In addition, studies show that surface and electrochemical characteristics of anode plate were conducive to generate a strong oxidizing environment around the plate for a more effective destruction of the pollutants.