Agro-Waste-Based Bio-Nanocomposite for the Mitigation of Pb (II) Ions from Water

Plentiful quantities of agro-waste are generated after utilizing commercially valuable parts of the agro-biomass and often go to waste or are burned in the open air, resulting in environmental pollution. Herein, bio-nanocomposite is prepared using agro-waste-based activated carbon as a support and loading waste peel-mediated synthesized nanoparticles over it. The method used is cost-effective and simple due to its ease of synthesis and the availability of tons of agro-waste for sustainable agro-waste management. In the present work, orange peel extract is used to synthesize iron-oxide nanoparticles (IONPs) that are loaded over activated carbon derived from ice-apple fruit shell waste (IFSAC), based on the seventh principle of Green Chemistry. Batch studies were conducted using bio-nanocomposite to evaluate its adsorptive removal efficiency for Pb (II) ions from water. The optimum conditions obtained for a Pb (II) ion concentration of 25 ppm were pH 5.5 at 40 °C for 120 minutes and stirring at 120 RPM. The maximum removal (99.44%) of Pb (II) at an adsorbent dosage of 0.2 g 10 mL^-1 of bio-nanocomposite was achieved. Kinetics and thermodynamic parameters were also calculated to determine the viability of removal. The findings demonstrated that agro-wastes could be converted into useful assets for the sustainable development of the ecosystem, viz. ice-apple shell residue-derived nanocomposites (IONP@IFSAC) was verified to be a cost-effective adsorbent for the mitigation of lead from water.