Performance of Natural Coagulant Extracted from Plantago ovata Seed for the Treatment of Turbid Water

摘要

Present study investigates the coagulation ability of Plantago ovata (P. ovata) seed extracts for turbidity removal. The active coagulant agents were successfully extracted from P. ovata seeds using different solvents such as distilled water (PO-DW), tap water (PO-TW), NaCl (PO-NaCl), and ammonium acetate (PO-AA). Experiments were conducted in batch mode for initial turbidity such as 500 NTU (high), 150 NTU (medium), and 50 NTU (low). Results demonstrated that P. ovata extracts are less efficient in low turbidities, while PO-NaCl was found to provide high coagulation activity in all initial turbidity concentrations compared to other extracts. PO-NaCl was able to remove 98.2, 94.9, and 80.2% of turbidity from water having in initial turbidities of 500, 150, and 50 NTU, respectively. Coagulation activity of the extract was the best when the extraction was performed for 50 min at room temperature. Jar test procedure with the coagulation time of 1 min and flocculation time of 30 min was optimized, irrespective of the initial turbidity. The optimum settling time for 500, 150, and 50 NTU water samples were 20, 30, and 90 min, respectively. PO-NaCl was used in different pH turbid solutions and it was found to be working very efficiently in alkaline conditions. The coagulation efficiency of the coagulant stored in refrigerator was higher than that stored at room temperature. Thus, the natural coagulants extracted from P. ovata seeds revealed to be effective for turbidity removal.