Eco-friendly biosorbent for lead removal: Activated carbon produced from grape wood

Abstract

This study looked into the removal of heavy metals from aqueous systems using carbon obtained from grape wood, an agricultural waste. Activated carbon was created by pyrolyzing and activating grape wood. Characterization of the material showed a highly porous structure with a large number of surface oxygen groups. In batch investigations, optimal conditions (pH 5, 25 °C, 100 mg L−1 starting Pb2+) resulted in an all-out lead uptake capability of 135.7 mg g−1. In 60 min, over 90% of the material was removed at a pseudo-second-order rate of 1.894 × 10−4 g mg-1 min-1. Adsorption had an all-out capability of 293.7 mg g−1, which was in line with the Sips model. Positive enthalpy (70.88 kJ mol−1) and entropy (0.2546 kJK−1mol−1) values from the thermodynamic analysis suggested chemisorption. Using HCl, the adsorbent could be renewed up to five times.