Efficiency of Sweet Lemon (Citrus limetta) Biochar Adsorbent for Removal of Chromium From Tannery Effluent

摘要

The present study investigated the efficiency of biochar prepared from peels of sweet lemon (C. limetta) for removing chromium (Cr) from tannery effluent by the process of adsorption. The adsorbent was used in the form of biochar and was characterized by SEM-EDXA and FTIR studies. The study was carried out in batch experiments to investigate the effect of different dosage of adsorbents at different time intervals at constant pH and temperature. The saturation point was found to be 0.5 gm/100 mL of tannery wastewater at 200 min of contact time with maximum removal efficiency of about 98%. The presence of different functional groups and morphological change on biochar enabled the efficient removal of chromium. Further, the adsorption of chromium onto the surface of biochar of the peels of sweet lemon favoured Langmuir adsorption isotherm in comparison to Freundlich adsorption isotherm, which demonstrates that the adsorption process has been monolayer and homogenous.