A study on the use of a waste by-product from saw-mill in the removal of basic dye from aqueous solution: kinetics and thermodynamics

Abstract

In the present study, an attempt has been made to use oak sawdust, a waste lignocellulosic by product from sawmill, as a potential adsorbent for basic dye (Astrozone Blue FGRL) removal from aqueous solution. The effects of contact time and temperature on Astrozone Blue FGRL (AB) adsorption by oak (Quercus coccifera) sawdust were studied. The experimental data at four initial dye concentrations (25, 50, 100 and 200 mg/L) were analyzed by the pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion kinetic models. Thermodynamic parameters, enthalpy change (Delta H), entropy change (Delta S), and Gibbs free energy change (Delta G) were calculated for the uptake of AB, and indicated that the adsorption was a spontaneous and endothermic process. Kinetic studies of the data showed that the adsorption follows the pseudo-second-order kinetic model.