Abstract

This study outlines the synthesis, physicochemical characterization, and pollutant removal capabilities of nanobiochar derived from coconut shell biomass. The biochar was produced through controlled pyrolysis at 800 °C for 3 hours and subsequently milled to achieve nanoscale dimensions. Dynamic light scattering analysis indicated an average particle size of 618.1nm with a polydispersity index, suggesting a moderately uniform nanoscale distribution. Structural analyses, complemented by BET surface area measurements, confirmed prominent aromatic features, several functional groups that include oxygen, and a large specific surface area of 422.7m²/g. The nanobiochar demonstrated a zeta potential of -83.38mV, indicating excellent colloidal stability. Batch adsorption experiments revealed high sorption capacities for methylene blue and Pb, with removal efficiencies exceeding 95% under optimal conditions. The pseudo-second-order Langmuir isotherm kinetics models offered the best fit for equilibrium and kinetic studies, respectively, suggesting a primary chemisorption process. These findings highlight coconut shell-derived nanobiochar as an economical and environmentally pleasant adsorbent for wastewater treatment and remediation.

Keywords:Coconut shell biomass; Nanobiochar; Pyrolysis; Surface area; Adsorption; Methylene blue; Water purification; Environmental remediation