Equilibrium and kinetic studies of the adsorption of sodium dodecyl sulfate from aqueous solution using bone char

In this study, bone char (BC) was used as an adsorbent for sodium dodecyl sulfate (SDS) in aqueous solution. Batch studies were performed to address various experimental parameters like contact time (0–360 min), adsorbent dosage (3, 5 and 7 g/L), initial SDS concentration (0.5, 1 and 2 mg/L) for the removal of the SDS. A greater percentage of SDS was removed with a decrease in its initial concentration, and an increase in the amount of adsorbent used. The maximum removal percentage of SDS for 0.5, 1 and 2 mg/L were estimated 80.2, 76 and 60.5 %. The maximum removal of SDS was obtained in the adsorbent dose of 7 g/L. Equilibrium isotherms were analyzed by Freundlich and Langmuir isotherm equations. The Freundlich equation is found to best represent the equilibrium data for the adsorption system. The kinetic study showed that the adsorption of SDS on BC was a gradual process. Pseudo-first order, pseudo-second order, Eluvich and intraparticle diffusion models were used to fit the experimental data. The intraparticle diffusion model was able to provide realistic description of adsorption kinetics.