Synergistic effect of cafeterias and domestic wastes for the removal of lead from aqueous solution

The purpose of this study is to investigate if an untreated mixture waste, such as cafeteria coffee grounds and domestic orange peels, can be used to remove Lead from aqueous solution. MW was characterized with SEM, FTIR and X-ray fluorescence analysis. Batch kinetic and equilibrium experiments were performed and the MW’s sorption efficiency was investigated by contact time, adsorbent dose, initial pH, initial Lead concentration and temperature. The equilibrium was attained in less than 30 min. Langmuir isotherm provided the best correlation for Pb 2 + adsorption to MW and showed favorable adsorption and a maximum adsorption capacity of 33.80 mg g −1 was found. The experimental knowledge was used to investigate the mechanisms of adsorption and possible rate-controlling steps for mass transfer and kinetic models. The adsorption of lead was influenced by both external mass transfer and intra-particle diffusion, and the kinetics of adsorption followed a pseudo second order model. The findings indicate that, in fact, Lead’s adsorption on MW is endothermic and spontaneous. The results suggest that MW has high potential and can be used as efficient and cost-effective adsorbent for removing Pb 2+ .