Biologia Futura: treatment of wastewater and water using tannin-based coagulants.

Abstract

Industrialization and urbanization are mainly responsible for environmental pollution generating enormous amount of wastewater which needs to be treated. Wastewaters from various sources are toxic to humans and livestock, as well as posing environmental risks. Various treatment approaches have been used for the elimination of contaminants from water and wastewater. Coagulation/flocculation processes are the most commonly used techniques in water treatment for improving the condition of turbid water and removing suspended particles by destabilization and the creation of larger, heavier flocs that aid in sedimentation. Flocculants, both organic and inorganic, have long been used in wastewater treatment. The use of natural coagulants/flocculants for water and wastewater treatment has become essential due to the health risks associated with chemical flocculants. Tannin, a natural coagulant, has been suggested as substitute of chemical coagulants. Tannins are present in the leaves, fruits, barks, roots, and wood of trees as a secondary metabolite. Tannin-based coagulants derived from a variety of plant sources have been successfully used in the treatment of water and wastewater. This review summarises the current status and strategies on applications of tannin-based coagulants exploiting the eco-friendly green materials in water and wastewater remediation for the sake of pollution free environment.