Improvement of the ferritization process for purifying concentrated wastewater from copper ions

The prospects for improving the environmental safety of industrial enterprises through the use of advanced wastewater treatment technology for the removal of heavy metal compounds are considered. The efficiency of copper ion removal from wastewater using the ferritization method under activation of the reaction mixture by ultraviolet and microwave irradiation was investigated. X-ray phase analysis of the resulting ferritization precipitates confirmed the presence of iron hydroxide, copper (I) and copper (II) oxides, as well as copper ferrite. The efficiency of copper ion removal by ferritization under ultraviolet and microwave activation was studied in detail. The influence of the ratio of heavy metals at an initial copper ion concentration of 2 g/L on the effectiveness of ion removal from copper-plating wastewater was determined. The best results were achieved under ultraviolet irradiation and a Cu²⁺/Fe²⁺ ratio of 1/2. Ultraviolet irradiation allowed the residual concentration of copper ions in water to be reduced to 2.03 mg/L, compared to 6.89 mg/L under microwave irradiation. The purification efficiency reached 99.90% with ultraviolet and 99.66% with microwave activation. A stable chemical phase of copper ferrite was formed during microwave activation of the reaction mixture at a Cu/Fe ratio of 1/3.5, with a content of 89.91% in the precipitate. The resulting water quality meets the requirements for reuse in electroplating operations for rinsing processes. Implementation of these research results at electroplating enterprises will contribute to the reduction of toxic emissions and the improvement of wastewater treatment technologies.