Utilization of Fly Ash as Low Cost Adsorbent for Treatment of Textile Dying Industry Effluents: Kinetics and Isotherms

Abstract--Textile dying industry effluents are highly toxic in nature and it contains a large number of complex metal dyes. Many dyes used in textile industries are stable to light and resistant to aerobic digestion. Thus removal of coloured waste from industrial dye effluent is a most perplexing problem to such industries and the environment. On the other hand fly ash is a major pollutant generated from coal based thermal power plants but it has good potential as adsorbents. In this present paper fly ash obtained from Kolaghat Thermal Power Plant (West Bengal) has been used to remove the dye, Methylene Blue from aqueous solutions. Experiments were done using the solutions with various concentration of dyes. The effect of adsorbent amount , contact time , solute concentration and temperature on percent removal of dye has been studied. Result shows that 8595% removal of dye may be achieved depending on adsorbent amount and solute concentration . An attempt has also been made to find out the Helfferich first order kinetics and Pseudo second order reaction kinetics for dyefly ash adsorption system . The applicability of the rearranged Langmuir isotherm model and Freundlich isotherm for this adsorption process has been investigated. Results show that fly ash generated from thermal power plant has good potential for waste water management, and it may be utilized as low cost adsorbent for dye removal from textile effluents.