Capacity and Mechanisms of Pb(II) and Cd(II) Sorption on Five Plant-Based Biochars

China is a large agricultural country that produces amount of crop straw every year. Thus, the development cost-effective and economic application invasive plants warranted. Biochars derived from have been proven to be promising for adsorbent materials. However, less studies focused on biochar different types as under same conditions compare their adsorption performance. Here, we characterized five biochars in system (600 °C). In results, GBC has higher ash content, pH, CEC, specific surface area, mineral composition oxygen-containing functional groups. The kinetics can explained adequately by pseudo-second-order model Langmuir model, indicating behavior both physical chemical adsorption; process includes complexation reaction, cationic π bond, ion precipitation electrostatic adsorption. conclusion, exhibited metal equilibrium capacities (125 mg·g−1 Pb2+, 29 Cd2+). solution dosing, pyrolysis temperature properties these heavy metals were responsible capacity, thus showing stronger affinity better effect. Our results are important selection utilization plant-based metals.