Adsorption of Pb2+ and Cd2+ in Agricultural Water by Potassium Permanganate and Nitric Acid-Modified Coconut Shell Biochar

Biochar prepared from agricultural waste resource coconut shells was used as the original charcoal, which oxidatively modified and characterized using batch adsorption tests before after modification by SEM, FTIR, surface area, elemental analyses. The removal capacity mechanism of biochar for Pb2+ Cd2+ in water were investigated, its kinetics thermodynamics discussed. findings demonstrated that specific area potassium permanganate nitric acid-modified shell carbon (MHBC) is 3.02 times than (BC). kinetic data on MHBC more accordance with pseudo-second order model, indicating chemical played a dominant role, rate gradually tended to balance decrease solution ion concentration. isothermal thermodynamic conformed Langmuir model. At pH = 5.5, maximum capacities 160.41 mg·g−1 47.46 mg·g−1, respectively. Thermodynamic parameter fitting showed process spontaneous endothermic reaction. higher temperature is, stronger is. When ions coexist, have obvious competitive adsorption, has significant advantage. Among them, high good reusability Cd2+, practical application prospects.