Performance of Solanum incunum Linnaeus as natural coagulant and disinfectant for drinking water

Abstract

The paper reports the performance of Solanum incunum Linnaeus as coagulant and disinfectant for water purification. The coagulation-flocculation experiment was carried out using a Phipps and Bird PB-700™ Jar Tester. Results show that coagulation depends on Fe(II) content and disinfectant on bioactive natural product compounds from the plant. Turbidity removals were 96, 97 and 75% for raw water with turbidity of 450, 300 and 105 NTU, respectively. Fecal coliform removal increased with coagulant concentration, displayed a maximum removal of 99% at 2.2 × 10^-4 g/ml. LD₅₀ ranged from 0.62-2.6 × 10^-5 g/ml, which were within the range of optimum coagulation concentration of 2.2 × 10^-5 g/ml. Turbidity and SO₄^2- concentrations for the treated water conforms to the Tanzanian Standards and WHO guidelines for drinking water, while fecal coliform counts exceeded the recommended values. The results suggest that S. incunum is promising as coagulant and disinfectant product for water purification.

Key words: Coagulant, disinfection, fecal coliform, Solanum, turbidity, water.