ADSORPTIVE REMOVAL OF AZOPHLOXINE DYE BEARING WASTEWATER

Abstract

Present study explores the adsorptive removal of azophloxine dye from aqueous solution onto bagasse fly ash (BFA), rice husk ash (RHA). Batch experiments were carried out to determine the influence of parameters like initial pH (pHo), contact time (t), adsorbent dose (m), temperature (T) and initial dye concentration (Co) on the removal of azophloxine. The optimum conditions have been found to be : For BFA pH0=6, Co= 100 mg/1, m=20g/1, t=5 h and T=60°C; For RHA: pHo=6, Co= 100 mg/I, m=25g/1, t=5 h and T=60°C. The removal efficiencies of BFA and RHA were found to be 97% and 95% .Results clearly shows that for the removal of azophloxine dye BFA is a better adsorbent as it gives more removal efficiency even at lower adsorbent dose in comparison to RHA. The various equilibrium isotherms have been studied and it has been found out that Langmuir isotherm fits better to the experimental data than other isotherms for azophloxine adsorption on BFA. For adsorption of azophloxine dye by RHA Freundlich isotherm isotherm fits better. For various Kinetic studies it has been found that for both BFA and RHA pseudo second order is the best fit observed. Since BFA and RI-1A is a waste material obtained at almost no cost, the spent BFA and RHA can be combusted to recover its energy value and the bottom ash can be blended with cementitious mixture for making building blocks.