Terminalia catappa (talisay) leaves as coagulant for preliminary surface water treatment

Abstract

At present, in order to decrease the hazards of using inorganic coagulants for preliminary water treatment, researchers have been studying the possibility of using new methods and materials to treat water. This study aimed to evaluate the performance of turbidity removal in water by using Terminalia catappa (Talisay) as natural coagulant.  The coagulation active agent in the leaves of Terminalia catappa was extracted with 1.0 molar (M) Sodium Chloride (NaCl) solution. Water from Cagayan River, Tuguegarao City, with increased turbidity of 200 Nephelometric Turbidity Units (NTU) was used in this study.  This study was done using Completely Randomized Design with loading doses of 2, 3, 4, and 5 ml/L of the stock solution with 5g of Terminalia catappa leaf powder in 100 ml 1.0 M NaCl solution as coagulant. The turbidity, pH, and coliform count were determined for all the samples. The turbidity for the samples ranged from log₁₀1.81 to log₁₀1.33 NTU. The 5 ml/L treatment of Terminalia catappa showed the lowest residual turbidity where 88% turbidity was removed from the sample. The pH values ranged from 7.27 to 7.46. The total coliform count for all treatments were all equivalent with >6500 cfu/ml. Hence, Terminalia catappa leaf extract possesses potential natural coagulant for surface water treatment due to its ability to remove turbidity. However, Terminalia catappa leaf extract has no effect on the basicity and acidity of the water sample. Furthermore, it has no observable antibacterial property on water.