Removal of heavy metal mixtures from wastewater of electroplating industry: article

Heavy metals from wastewater of electroplating industry have caused major hindrance to inland water pollution. Heavy metals are currently removed by the coagulation-flocculation process. This method had been chosen due to low operational cost and high removal efficiency. The present investigations mainly focused on single element treatment. However, in the actual wastewater, there were complexes of multi-metals present. Therefore, the research work is focused on removal multi-metals which included Copper (Cu), Cadmium (Cd), and Zinc (Zn) from two different characteristic of synthetic wastewaters which prepared according to the actual characteristic of wastewater from electroplating industries. Jar test was conducted by using two different methods known as Method A and Method B. The parameters of the study were initial pH adjustment and Ferric Chloride (FeCl₃) dosage. Results shows the optimum removal condition obtained from Method A for both wastewaters type I and type II is at pH 10 of pH adjustment and FeCl₃ dosage of 140 mg/L and 100 mg/L respectively. The efficiency of heavy metals removal for both wastewater characteristics were approximately 99%. The selected data obtained were fitted using multilinear regression via Microsoft Excel. The regression analysis shows adjusted R² obtained for all metals from wastewater type I are above 90% which indicate the best fitting data. The ANOVA analysis proved that the mathematical expression can be used to predict the removal of multi-metals from wastewater solution.