Enhanced lead (II) adsorption from aqueous solution using sawdust-derived amino-decorated cellulose: Optimization, isotherm, kinetics, and reusability studies

Water pollution, driven by Pb2+, poses a significant threat to biotics and the environment. A promising solution to address the issue is the utilization of cellulose from lignocellulosic materials as an adsorbent to remove or reduce Pb2+ from wastewater. However, as reported, the adsorption capacities of native cellulose adsorbents vary depending on their plant source, and their metal binding capacity is not as satisfactory as expected due to a lack of robust chelation sites, particularly amino groups. Thus, this study aimed to improve Pb2+ uptake capacity by utilizing the prosopis juliflora stem, a previously unexplored cellulose source, as an adsorbent through ethylenediamine (EDA) grafting. FTIR, XRD, FE-SEM, EDX, and TGA evaluated the physicochemical properties of amino-decorated cellulose (ADC) adsorbent. The effect of experimental variables (initial Pb2+ concentration, ADC dose, and contact time) on percent removal was investigated and analyzed using Box-Behnken Design (BBD). Analysis of variance (ANOVA) revealed that, among the interaction effects, only the interactions between initial Pb2+ concentration and ADC dose significantly affected percent removal (P