Exploration of Various Indonesian Indigenous Plants as Natural Coagulants for Synthetic Turbid Water

Abstract

The availability of clean water is one of the biggest global problems, especially in developing countries. The simplest way to treat turbid water is by using coagulation. However, the utilization of chemical coagulants such as alum and ferrum has several drawbacks, including a high sludge volume and negative health impact when the water is consumed. Natural coagulants offer a better option, especially because of their availability, low price, lower sludge volume, and effectiveness comparable with chemical coagulants. In this study we utilize Moringa oleifera, Carica papaya and Leucaena leucocephala seeds, which are indigenous plants in Indonesia, as natural coagulants. An FTIR study was conducted to qualitatively identify the possible active coagulant agent in the seeds. The coagulant performance in removing turbidity of synthetic kaolin water was studied using jar test apparatus at various levels of coagulant dosage and pH. Functional groups of –OH, N-H, C=O, and primary, secondary and tertiary amides were identified in all the seeds. Neither the dosage nor the pH had an effect on turbidity removal when M.oleifera was used as the natural coagulant, but did have some effect on papaya and leucaena. The turbidity removal obtained in this study was comparable with other reported results, therefore it can be concluded that these seeds have the potential to be used as natural coagulants.