Fabrication of Biochar-Impregnated MnO₂ Nanocomposite: Characterization and Potential Application in Copper (II) and Zinc (II) Adsorption

Abstract

Environmental water pollution currently deserves growing attention due to water contamination, because water is an essential element on earth. The presence of heavy metals released from wastewater effluents from different industrial plants has become a great concern to treat water. Developing a novel material with enhanced adsorption efficiency has become a difficult task; therefore, in the present study, nanocomposite (Mn-SCL BC) was synthesized using biochar derived from plant biomass Saccarum ravvanne and decorated with manganese dioxide used to remove toxic heavy metals from water. The effects of pH, adsorbent dose, contact time, and concentration on the adsorption were studied to know the interaction of heavy metal ions and adsorbent. The kinetics studies confirm pseudosecond-order kinetics for the adsorption of copper (II) and zinc (II). Two nonlinear isotherm models, Langmuir and Freundlich, were used. The highest R2 value reveals the Langmuir adsorption isotherm. The maximum monolayer adsorption efficiency is found to be 1,124 and 995 mg/g for copper (II) and zinc (II), which is relatively higher than other materials found in the literature. The findings investigated here suggest that MnO2-functionalized nanocomposite (Mn-SCL BC) has an eco-friendly, economical, and alternative adsorbent with potential applicability for the adsorption of heavy metal ions from aqueous media.