Researching the Oxidation Process of Sulfur-Alkalaine Sewage Components Using Ni<sup>2</sup>+ Catalyst -Containing Galvanic Wastewater
The effect of different concentrations of nickel (II) ions on the oxidation rate of mixed wastewater pollutants with ozone-air mixture for 30 minutes with an ozone concentration of 3 mg/l was studied. It was shown that adding nickel (II) ions at a concentration of 300 mg/l reaches the maximum degree purification of wastewater as a result of oxidative processes on the COD value, equal to 40.4%, which is 10.1% more compared to the catalytic oxidation of the investigated wastewater pollutants with the air oxygen participation. As a result of the conducted research, optimal conditions for the implementation of effective wastewater treatment of chemical production using Ni2+ catalyst-containing electroplating wastewater that is oxidation of pollutants with ozone-air mixture containing 300 mg/l of nickel (II) ions for thirty-minute sparging. At the same time, total degrees of wastewater treatment in terms of COD and alkalinity, equal to 90,0% and 94,2%, respectively, were achieved. The greatest purification effect was revealed when using Ni2+-containing galvanic wastewater as a catalyst as compared to using Cu2+-con-taining galvanic effluent, while the difference in the degree of purification of wastewater at the stage of oxidation of pollutants by COD value was 10.1%.