LIGNIN AS AN ADSORBENT FOR THE REMOVAL OF DYES FROM WASTE WATER

Abstract

Untreated colored effluents from textile and dyestuff industries are resistant to biochemical oxidation, highly toxic to marine and human life and carcinogenic in nature. They are stable in light, impede light penetration into receiving waters and upset the biological activity of the natural flora and fauna. Amongst the various physico-chemical treatment processes used for removing pollutants, adsorption has been found to be an effective, economical and an easy method for the removal of color from contaminated wastewater. Activated carbon has not found favor in view of economical considerations and regeneration difficulties. The results on other adsorbents, mainly agro residues and industrial wastes, are also not very encouraging. Lignin is a waste material present in the black liquor of the pulp and paper industry that possesses problem of its disposal. It shows good sorption properties and has been chosen as an adsorbent for the removal of dyes from wastewater.