Investigation of Pumpkin Seed as a Potential Coagulant for Drinking Water Treatment

Studies pointed out that using synthetic chemical coagulants for water purification presents health and environmental problems. Because of this, there has been considerable interest in utilizing natural coagulants emerging as potential substitutes for them. Hence, the objective of this study is to investigate and optimize pumpkin seed as a natural coagulant for water treatment. After preparation and characterization of the coagulant under study, the optimal dose of the coagulant, pH, and effect of stirring speed on coagulation for the removal of turbidity were conducted through a series of jar tests. Response surface methodology was also employed to optimize conditions for treating the water sample using the coagulant to remove its turbidity. Analysis of the result showed that optimal conditions for coagulation were pH 9, coagulant doses 1.01 g/L, and mixing speed 135.76 rpm. Under this optimal condition, the achieved efficacy of turbidity reduction was 87.69%. The qualities of the treated water sample obtained using pumpkin seed as coagulant were temperature 22.3 °C, pH 7.99, turbidity 39.6 NTU, hardness 97.13 mg/L, TDS 110.33 mg/L, TSS 13.46 mg/L, TS 123.79 mg/L, EC 179 μS/cm, BOD 20 mg/L, and COD 26.64 mg/L. Hence, pumpkin seed powder might be presented as a potential natural coagulant to remove turbidity in drinking water treatment process to seek for solutions associated with the problem of synthetic chemical coagulants.