Adsorptive removal of Pb²⁺ from wastewater using ZnO-Biochar nanocomposite

The discharge of lead (Pb²⁺) from industries, which is harmful to water, human health and food chain, poses a serious risk. Due to the remarkable ability of ZnO biochar nanocomposite to remove Pb²⁺ from wastewater, it gained significant attention in environmental research. This study was conducted to determine how effectively the prepared ZnO-Biochar nanocomposite removed Pb²⁺ from wastewater. Fourier transmission infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to examine the functional groups and surface morphology of the ZnO-Biochar nanocomposite, respectively. The structure of ZnO-Biochar nanocomposite with rough and porous surface performed the positive association in surface adsorption of Pb²⁺ pollutant. A batch-experimentation conducted under a variety of conditions, including initial Pb²⁺ concentration (50-200 mg L⁻¹), adsorbent dosage (0.05-0.25 g), pH (2-12), and contact time (0-240 min) to evaluate the removal rates as well as adsorption capacities, within an emphasis on environmental impact. This study proves that ZnO-Biochar nanocomposite has a 90.30% removal rate for Pb²⁺. The ZnO-Biochar nanocomposite proved an impressive maximum adsorption capacity (q_max) of 79.302 mg/g, as determined through the implementation of the Langmuir model. A linear pseudo-first order and pseudo-second order model having R² values of 0.867 and 0.899 respectively, show the best fit for the experimental data concerning Pb²⁺. Experiments conducted in this work demonstrate the exciting potential of the prepared material for promoting sustainable treatment of industrial wastewater.