Adsorption of Lead (II) from Aqueous Solution with High Efficiency by Hydrothermal Biochar Derived from Honey

摘要

A novel natural honey hydrothermal biochar (HHTB) was prepared using natural honey as raw material. The as-prepared adsorbent was applied to adsorb Pb from aqueous solution and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy to investigate the structure and morphology change of the adsorbent before and after Pb adsorption. The influence of the pH, initial Pb concentration, temperature, and contact time on the adsorption of Pb was systematically investigated. The results revealed that the adsorption capacity for Pb is up to 133.2 mg·g at initial pH of 5.0 and adsorption temperature of 298 K. Meanwhile, the adsorption of Pb on HHTB can be well fitted by the pseudo-second-order model and Langmuir isotherm model. The adsorbent had great selectivity for Pb from the aqueous solution containing coexisting ions including Cd , Co , Cr , Cu , Ni and Zn . Furthermore, the adsorption of Pb on HHTB was attributed to complexation coordination, where it involved hydroxyl and carboxylic groups on HHTB in the process of adsorption of Pb .