Investigation of nickel removal from heavy metal containing industrial wastewater by electrocoagulation method

Abstract

In the study, Ni2+ (nickel) removal from synthetically prepared wastewater by electrocoagulation method, which is one of the electrochemical treatment processes, was investigated and parameters such as current density, pH, mixing speed, initial Ni2+ concentration, supporting electrolyte type and concentration were determined to determine Ni2+ removal efficiencies effects were studied. Experiment conditions during 30 minutes of electrolysis; the current density was determined as 0.95 mA/cm2 , the initial pH of the wastewater was 6, the mixing speed was 150 rpm, and the initial nickel concentration was 250 mg/L. The Ni2+ removal efficiency was obtained as 75.99% under the determined experimental conditions, while the energy consumption was calculated as 3.15 kW-h/m3 . In the experiments, it was observed that the type and concentration of the supporting electrolyte did not have a significant effect on the Ni2+ removal efficiency. In the trials where the effect of the support electrolyte concentration was examined, the Ni2+ removal efficiency was 75.99% in the wastewater environment without the supporting electrolyte, while the Ni2+ removal efficiency was 81.55% when 7.5 mmol/L NaCl was used after the 30-minute reaction, and the energy consumption was 2.15 kW-h/m3 obtained as. As a result of the studies, it was concluded that the electrocoagulation process can be applied in the treatment of wastewater containing Ni2+