Application of copper(II) oxide of electrocoagulation products of electroplating waste water as ceramic glaze dyes

Abstract

This study aims to determine the effect of combustion temperatures and copper(II) oxide concentrations on ceramic glaze color. Electrocoagulation process was carried out using optimum conditions: pH 8, electrocoagulation time of 120 minutes, Al-Fe electrodes, and current density of 1.25 mA/cm2. Experiment variables include combustion temperatures (999, 1060, 1101 °C) and copper(II) oxide concentrations (0.88; 1.76, 2.64, 3.53% ). The results of the coagulant characterization with XRF showed copper(II) content of (22.04 ± 0.73)%. Besides that it also contains of other metals such as Cr, Cd, and Pb however below the detection limit. Coagulant is a metal hydroxide which is dried and calcined formed the oxide. Then, it was applied as a glaze ceramic dye. Based on the analysis of homogeneity using chromameter, the brightness value (L∗) increased at the combustion temperature of 999 and 1060 °C, but at a temperature of 1101 °C it decreased. The green color value (a∗) decreases when the combustion temperature is raised but the yellow value (b∗) increased. When the metal oxide concentration was increased, L∗ and a∗ values decreased. While the b∗ value increased at a concentration of 0.88 to 1.76%, but at a concentration of 2.64 to 3.53% decreased.