Abstract: This study used agricultural waste silk gourd complex powder as raw material and sodium bicarbonate as activator to prepare sodium bicarbonate modified biochar (SBC) that can efficiently adsorb carbamazepine (CBZ) in water through impregnation pyrolysis method. The physical and chemical characteristics such as surface morphology, pore size distribution, functional groups, and degree of graphitization are analyzed through characterization methods. The effects of temperature, dosage, pH and other factors on the adsorption of CBZ in water by SBC are studied through batch experiments. The results show that compared to the original biochar (BC), SBC has a higher specific surface area of 531.43 m2/g and a richer pore size structure. The effect of pH on the adsorption of CBZ by SBC is minimal, and SBC is almost unable to adsorb large molecular humic acids. The Sips model can better describe the adsorption equilibrium law of CBZ on SBC, with an adsorption capacity of 125.52 mg/g at 298 K. Thermodynamic analysis shows that the adsorption of CBZ by SBC is a spontaneous endothermic process, with physical adsorption being the main process. By analyzing the energy distribution of SBC sites and density functional theory, the enhanced adsorption mechanism of CBZ on SBC is further explored. The results show that hydrogen bonding, π-π electron acceptor donor, and pore filling are involved in the process of SBC adsorption of CBZ. Methanol can effectively regenerate saturated SBC, and after four adsorption desorption cycles, the adsorption capacity of SBC for CBZ remains at 68.132 mg/g. This article uses agricultural and forestry waste sponge gourd as a carbon source to prepare biochar for removing pollutants from water, providing a feasible approach to simultaneously achieve the resource utilization of agricultural waste and reduce environmental pollution.

Key words: biochar, sodium bicarbonate, adsorption, carbamazepine, site energy distribution (SED), density functional theory (DFT)

摘要： 本研究以农业废弃物丝瓜络为原材料，采用碳酸氢钠为活化剂，通过浸渍-热解法制备出了可高效吸附水中卡马西平(CBZ)的碳酸氢钠改性生物炭(SBC)，并通过表征手段分析了其表面形貌、孔径分布、官能团、石墨化程度等物理化学特征。通过批量实验研究了温度、投加量、pH等因素对SBC吸附水中CBZ的影响。结果显示，相比原始生物炭(BC)，SBC有着更高的比表面积531.43 m2/g和更丰富的孔径结构。CBZ的去除效率随着SBC投加量的增加而增加。溶液pH对CBZ去除的影响不明显。Sips模型可以更好地描述SBC对CBZ的吸附平衡规律，在298 K时的吸附容量可达125.52 mg/g。热力学分析表明SBC对CBZ吸附为自发吸热过程，且以物理吸附过程为主。通过对SBC的位点能量分布分析和密度泛函理论分析进一步探究了SBC对CBZ的增强吸附机理。结果显示氢键、π-π电子受体-供体和孔填充作用参与了SBC吸附CBZ的过程。甲醇可有效再生吸附饱和的SBC，经过四次吸附脱附循环后，SBC对CBZ的吸附量仍保持在68.132 mg/g。本工作以农林废弃物丝瓜络为炭源制备生物炭去除水中污染物，为同时实现农业废弃物资源化和消减环境污染提供了一条可行途径。

关键词: 生物炭, 碳酸氢钠, 吸附, 卡马西平, 位点能量分布, 密度泛函理论