Evaluation of plant based natural coagulants for surface water treatment of Pratapgarh District Uttar Pradesh, India

The efficacy of three plant-based natural coagulants, namely papaya seed powder, banana peel powder, and lemon peel powder, was evaluated in this study for their ability to remove high electric conductivity turbidity, hardness, fluoride, and nitrate from surface water. The experiments were conducted at room temperature without any adjustment to the initial pH. The results indicated that banana peel powder exhibited the highest turbidity removal rate, achieving 55.6% removal when used at a dosage of 0.4 g/L. Furthermore, banana peel powder demonstrated excellent removal efficiency for fluoride and nitrate, with 85% removal observed at the same dosage. Lemon peel powder also exhibited significant effectiveness, achieving 60% removal. Papaya seed powder proved to be the most efficient coagulant for removing hardness, demonstrating a removal rate of 69.66%. The study further revealed a noteworthy linear relationship between the removal of turbidity and hardness, as evidenced by correlation coefficients (R2) ranging from 0.67 to 0.88. Similar linear relationships were observed for turbidity removals, with R2 values ranging from 0.68 to 0.8. An additional advantage of using these natural coagulants was that they did not cause any pH alteration in the treated surface water. Moreover, Fourier-transform infrared (FTIR) analysis of banana peels indicated the presence of functional groups such as carboxylic acid, hydroxyl, and aliphatic amines. These functional groups likely play a crucial role in facilitating coagulation and flocculation by neutralizing the charges of impurities in the water. This study suggests that inexpensive natural coagulants hold promise for surface water treatment, offering a viable alternative to conventional methods.