Fly Ash for Removal of Malachite Green Dye From Wastewater: Kinetic and Isotherm Studies

Abstract

The release of toxic dye components from dye manufacturing industries has become a severe threat and causing water contamination. Adsorption is one of the common techniques, employing solid adsorbents such as activated carbon, alumina silica, wood, Fuller’s earth, fired clay, and metal hydroxides to remove traces of dye components from water. In India, every year 180 million tons of fly ash is produced and the disposal of the same is a major issue. To address the disposal problem, one of the best practices is to use flue ash as an adsorbent. In the present work flue ash has been used to remove components of malachite green dye from concentrated stock solution. A set of experiments in batch mode were performed to test the potential of flue ash for the removal of Malachite Green and the effects of parameters such as such as time of contact, pH, concentration of adsorbate, adsorbent dosage. Dynamic Light Scattering (DLS) technique is used to determine the average particle size of flue ash. Study on adsorption isotherms and adsorption kinetics was performed and most suitable models for adsorption isotherms and rate kinetics were proposed.