Adsorptive Removal of Ibuprofen from Waste Stream Using Sawdust-Based Adsorbents

Abstract

Wood sawdust, one the high volume agricultural wastes in Nigeria, occupies space and constitutes environmental nuisance. Burning, it produces green house gases. Converting it to adsorbents is economical and environmental benign. This work assessed the adsorptive capacities of two Danielliaoliveri sawdust-based adsorbents for the removal of ibuprofen from waste stream. The sawdust was carbonized and activated with ZnCl2 and H3PO4 to produce adsorbents code-named ZCAC and PAAC respectively. The physicochemical properties of the adsorbents were determined and batch adsorption experiments performed. The optimum pH for the adsorption of ibuprofen onto the ZCAC and PAAC was 3. The isotherm studies revealed that the Ibuprofen (IBU)-ZCAC system data fitted Redlich-Peterson and Langmuir models. The data also fitted Pseudo-second order and Boyd kinetics, defined intraparticle diffusion of the adsorbate molecules. The process was physical and endothermic. For the adsorption onto PAAC, the data fitted the Freundlich and the Halsey models. The data also fitted the Pseudo-second order and the Elovich kinetics. The process was endothermic. The adsorption capacities of ZCAC and PAAC for IBU were 3.876 and 15.385 mg/g respectively. ZCAC and PAAC were promising adsorbents for remediation of wastewater contaminated with ibuprofen.