EXTRACTION OF CU2+, ZN2+ AND NI2+ CATIONS FROM INDUSTRIAL WASTEWATER BY IONITE KU-2-8

The object of the research is model solutions of wastewater and wash water from metal processing enterprises containing copper, nickel and zinc ions. One of the most problematic places is that the process of sorption of copper, nickel and zinc cations on the strongly acidic cation exchanger KU-2-8 at high metal concentrations is not well understood. The sorption and desorption processes of Cu2+, Zn2+ and Ni2+ ions on KU-2-8 cation exchanger in the H+ form are studied using model solutions of metal sulfate at high concentrations. The experiments were carried out in an ion-exchange column with a diameter of 2 cm 2 loaded with cation exchanger with a volume of 20 cm 3. During the research, the concentration of metals was measured by titrometric, photometric and instrumental methods (concentration of copper, zinc and nickel ions, acidity, alkalinity, pH). Model solutions of heavy metal ions Cu2+, Zn2+ and Ni2+ with a concentration of 10, 20, and 50 mg-Eq/dm3 were passed through KU-2-8 ion exchanger in the H+ form. During sorption of 0.01 n model solutions, the ion exchanger capacity on average reached 2073 mg-Eq/dm3, at 0.02 n – 2140 mg-Eq/dm3 and at 0.05 n – 2100 mg-Eq/dm3. After metal extraction from model solutions and complete saturation of the ion exchanger, the conditions for the regeneration of cation exchanger in the Cu2+, Zn2+ and Ni2+ form with solutions of 5, 8 and 10 % sulfuric acid were studied. The efficiency of desorption of divalent metal ions from an ion exchanger was almost 100 %. The scientific novelty of the work lies in the fact that metal ions were sorbed for the first time at concentrations of 10, 20, and 50 mg-Eq/dm3 in terms of metal and their desorption of 5, 8, and 10 % sulfuric acid from cation exchanger. After the experiments, a scheme for washing water treatment using ion exchange and electrolysis was proposed, which will allow the organization of environmentally friendly metal processing processes at galvanic enterprises