MATHEMATICAL MODELLING BASED ON THE RESPONSE SURFACE METHODOLOGY (RSM) OF LEAD REMOVAL IN SYNTHETIC WASTEWATER USING CORIANDRUM SATIVUM AS BIOSORPTION

Abstract

Water pollution is a serious environmental issue that needs urgent concern from the government and the non-government board. There is the necessity to treat wastewater with high heavy metal content concentration to the permissible standard limit to protect the aquatic ecosystem. This study investigated the optimum condition for lead removal from synthetic wastewater (industrial wastewater) using the Coriandrum Sativum as a medium for lead extracting. Response surface methodology (RSM) by central composite design (CCD) was employed as the experimental design, in which three operational variables including the pH (4-10), retention time (30-180 minutes), and agitation speed (100-300 rpm). The focus of the study was lead removal. Through the optimization and validation process of the data, the highest removal efficiency of the lead was 74.68% (initial concentration of the lead for synthetic wastewater = 20 mg/L) was obtained at the following optimum condition: pH 6.16, the retention time of 180 minutes, and the agitation speed was at 254rpm. The values predicted from the models agreed satisfactorily with the experimental values, which implied that RSM was reliable and practical for experimental design developed using optimization of the lead removal in the wastewater.