Adsorption of Methylene Blue Dye from Industrial Effluents Using Coal Fly Ash

Abstract

Industrial Wastewater contains several type of dye, causing serious environmental hazard. The discharge of highly colored effluents into natural water bodies not only is aesthetically displeasing, but also impedes light penetration, thus upsetting biological processes within stream and thus required treatment before discharge into a water body. In the present study, fly ash generated from coal based thermal powers station has been converted into a low-cost adsorbent for the removal of Methylene Blue from effluents of textile industry. Batch studies have been carried out to study the effect of pH, adsorbent doses, adsorbate concentration, temperature and contact time. The results of batch studies reveal that the adsorption of Methylene Blue is strongly pH dependent and maximum Methylene Blue removal is observed at equilibrium pH of 7.0. Optimum adsorbent dose and contact time are found to be 10 g/l and 360 minutes respectively. Kinetic studies have been performed to have an idea of the mechanistic aspects and to obtain the thermodynamic parameters of the process. The results also show that adsorption decreases with increase in temperature thereby showing the process exothermic in nature. Adsorption data have also been correlated with both Langmuir and Freundlich isotherm models