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

• Main Authors: Bo Wang, Jie Yu, Hui Liao, Wenkun Zhu, Pingping Ding, Jian Zhou
• Format: Article
• Language: English
• Published: MDPI AG 2020-05-01
• Series: International Journal of Environmental Research and Public Health
• Subjects: honey; hydrothermal carbon; adsorption; water pollution; lead (II)
• Online Access: https://www.mdpi.com/1660-4601/17/10/3441
• ISSN: 1661-7827; 1660-4601

A novel natural honey hydrothermal biochar (HHTB) was prepared using natural honey as raw material. The as-prepared adsorbent was applied to adsorb Pb²⁺ 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 Pb²⁺ adsorption. The influence of the pH, initial Pb²⁺ concentration, temperature, and contact time on the adsorption of Pb²⁺ was systematically investigated. The results revealed that the adsorption capacity for Pb²⁺ is up to 133.2 mg·g⁻¹ at initial pH of 5.0 and adsorption temperature of 298 K. Meanwhile, the adsorption of Pb²⁺ on HHTB can be well fitted by the pseudo-second-order model and Langmuir isotherm model. The adsorbent had great selectivity for Pb²⁺ from the aqueous solution containing coexisting ions including Cd²⁺, Co²⁺, Cr³⁺, Cu²⁺, Ni²⁺ and Zn²⁺. Furthermore, the adsorption of Pb²⁺ on HHTB was attributed to complexation coordination, where it involved hydroxyl and carboxylic groups on HHTB in the process of adsorption of Pb²⁺.