改性生物炭对 Sb (Ⅲ) 的吸附效果及机理

Adsorption Effect and Mechanism of Sb(Ⅲ) by Modified Biochar

中文关键词: 生物沥滤  磁性生物炭  三价锑  吸附

英文关键词: bioleaching  magnetic biochar  Sb(Ⅲ)  adsorption

中文摘要:

      重金属锑 (Sb) 污染已严重危害人体健康和生态安全。文章通过生物沥滤法将离子态铁负载到生物炭上热解制备出碳基铁改性材料 (FBC)，改性后对 Sb (Ⅲ) 最大吸附量为 86.67 mg/g，较改性前提高了 459.52%；FBC 投加量为 1.0 g/L 时，pH 在 (3~11) 范围对水溶态 Sb (Ⅲ) 去除率达到 67.51%~87.27%。FBC 对 Sb (Ⅲ) 的吸附过程符合准二级动力学模型和 Langmuir 模型。热力学结果表明该吸附为自发放热过程，表征分析证实了其去除机理可能为：孔隙填充、氧化、表面络合、共沉淀和静电吸附等；与改性前相比，采用生物沥滤法制备的铁改性生物炭对水体 Sb (Ⅲ) 去除具有较高的抗干扰去除能力和重复利用价值，文章将为重金属 Sb (Ⅲ) 水处理工艺提供一种新思路。

英文摘要:

      The pollution of heavy metal antimony (Sb) in environment has seriously harmed human health and ecological safety. In this study, a carbon-based iron-modified material (FBC) was prepared by loading ionic iron onto biochar via bioleaching followed by pyrolysis. The modified FBC exhibited a maximum adsorption capacity of 86.67 mg/g, representing 459.52% enhancement compared to the unmodified material. Using 1.0 g/L of FBC, the removal efficiency for Sb(Ⅲ) in water reached 67.51%~87.27% across a broad pH range (3~11). The adsorption process of Sb(Ⅲ) on FBC conformed to the pseudo-second-order kinetic model and Langmuir isotherm. Thermodynamic results indicated a spontaneous and exothermic adsorption process. Instrumental characterization revealed that the removal mechanisms likely involved pore filling, oxidation, surface complexation, coprecipitation, and electrostatic interactions. The study demonstrates that the ironmodified biochar prepared via bioleaching exhibits high anti-interference capability and reusability, our experiment will provide a novel method in Sb(Ⅲ)-contaminated waste water treatment.