Perspectives of Coagulation for the Removal of Contaminants from Pharmaceutical Wastewater utilizing cucurbita seed as bio-coagulant

Abstract

Pharmaceutical effluent is a hazardous waste of environmental concern due to the complex nature of its chemical composition. This research focused on using coagulation techniques to remove contaminants from aqueous solution via investigating the coagulation qualities of cucurbita seed on removal of total suspended solid (TSS), color, chemical oxygen demand (COD), and turbidity from pharmaceutical effluent. The batch system was applied to evaluate the effect of process-independent variables on the coagulation process. The coagulation kinetics were investigated using first-order and second-order kinetic expressions. The optimum removal efficiency of contaminants was predicted using the response surface methodology (RSM) model. The batch study results show maximum color and turbidity removal of 77% and 68% at pH 6, whereas COD and TSS removal is 55% and 60% at pH 8. The results also confirm the process to be dependent on coagulant dosage, reaction time, mixing speed, settling time, and temperature. The concordance RSM model's actual optimum color removal efficiency of 97.99% and R² of 0.9914 with the model's predicted removal efficiency of 97.63% and predicted R² of 0.9298 thereby indicate the accuracy of the model prediction. These obtained results confirm cucurbita seed as a reliable, cost-effective alternative coagulant for contaminant removal from pharmaceutical effluents.