A comparative evaluation for adsorption of dye on Neem bark and Mango bark powder

Ruchi Srivastava, D Rupainwar
2011 Indian Journal of Chemical Technology   unpublished
The use of low cost adsorbent has been investigated as a replacement for the current expensive methods of removing dyes from wastewater. As such, Neem bark and Mango bark generated as a wood waste is collected and converted into a powder form and then used as a low-cost adsorbent for removal of dyes from wastewater. Adsorption studies are carried out at different temperatures, pH, initial dye concentrations and adsorbent doses. The adsorption of malachite green (dye) is found to increase with
more » ... crease in temperature. The linear form of Langmuir and Freundlich models fitted the adsorption data. The results indicated that Langmuir adsorption isotherm fitted the data better than Freundlich isotherm. Thermodynamic parameters such as the free energies, enthalpy and entropy of adsorption of the dye-Mango bark, Neem bark powder systems are also evaluated. The negative values of free energy indicated the feasibility and spontaneous nature of the process, and the positive heats of enthalpy suggest the endothermic nature of the process. The adsorption of Malachite green follow the second-order kinetics in both the adsorbents.