【摘要】 煤胶体大量存在于煤矿区周边，具有良好的吸附能力，会通过降雨或降尘形式进入水体和土壤环境。煤胶体表面性能优良，能够对土壤环境中的重金属迁移产生促进作用。本研究系统阐明煤胶体对铅和锌的吸附特性，为预测铅和锌在土壤中迁移提供重要依据。采用离心法和沉降法从褐煤中提取3种粒级煤胶体，研究了煤胶体对铅和锌的吸附行为。结果表明：粒级越小，比表面积和总孔容量越大，煤胶体对铅和锌的吸附量越大；准二级动力学方程能更好地描述煤胶体对铅和锌的吸附动力学过程，化学吸附为主要的吸附类型；铅和锌吸附平衡时间存在差异，铅和锌的吸附平衡时间分别为8和12 h;Freundlich等温吸附模型能较好的描述各粒级煤胶体对铅和锌的等温吸附过程，煤胶体对铅和锌的吸附过程属于表面和多分子层吸附；煤胶体对铅和锌的吸附是自发进行的熵增吸热反应，反应温度越高，越有利于煤胶体对铅和锌的吸附。该研究表明，褐煤胶体对重金属铅和锌的吸附性能较好，能够用于评估重金属在土壤中的环境行为。更多还原

【Abstract】 Coal colloids are abundant in the vicinity of coal mining areas and possess strong adsorption capabilities, often entering aquatic and soil environments through rainfall or dust deposition. With excellent surface properties, coal colloids can facilitate the migration of heavy metals in soil environments. This study systematically elucidated the adsorption characteristics of coal colloids for lead(Pb) and zinc(Zn), providing a crucial basis for predicting the migration of Pb and Zn in soils. Using centrifugation and sedimentation methods,three particle size fractions of coal colloids were extracted from lignite to investigate their adsorption behavior toward Pb and Zn. The results indicated that smaller particle sizes have larger specific surface areas and higher total pore volumes, leading to increased adsorption of Pb and Zn. The pseudo-second-order kinetic model better described the adsorption kinetics of Pb and Zn on coal colloids, with chemical adsorption being the dominant mechanism. Equilibrium times differed for Pb and Zn, at 8 and 12 hours, respectively. The Freundlich isotherm model effectively characterized the isothermal adsorption processes of various particle sizes, indicating that adsorption of Pb and Zn on coal colloids involves surface and multilayer adsorption. The adsorption of Pb and Zn on coal colloids was a spontaneous, entropy-driven endothermic reaction, with higher temperatures favoring greater adsorption. This study demonstrated that lignite-derived coal colloids exhibit excellent adsorption performance for heavy metals Pb and Zn, which can be utilized to assess the environmental behavior of heavy metals in soils.更多还原