改性活性炭对内分泌干扰物的吸附效能与机制

为提高活性炭对内分泌干扰物的吸附效率，分别采用混合酸溶液，氨水，KMnO₄溶液和表面活性剂溶液对活性炭进行改性.采用比表面积及孔隙度分析仪、扫描电子显微镜（SEM）、傅里叶红外光谱（FT-IR）和Boehm滴定法对改性后活性炭表面化学性质及孔隙特征的变化进行评价.通过静态吸附实验确定活性炭的最佳改性方法，并对改性后活性炭吸附机理进行探讨.实验结果表明，KMnO₄改性活性炭（AC-K）表现出最佳的污染物吸附性能，其对邻苯二甲酸二丁酯（DBP）、阿特拉津（Atrazine）和磺胺甲恶唑（SMZ）的去除率分别可达到94.5%、93.8%和95.5%，且吸附过程符合二级动力学方程和D-R模型.由模型计算结果可知，AC-K对目标污染物的吸附速率明显加快，其中对Atrazine的二级吸附速率常数是AC的1.75倍.AC-K对DBP、Atrazine和SMZ的理论饱和吸附量也分别比改性前分别提高了42.2%、629%和122%.经KMnO₄改性后，活性炭的吸附机制由物理吸附占主导，转化为离子交换吸附.

Adsorption efficiency and mechanism of endocrine disrupting compounds by modified activated carbon

In this paper, activated carbon (AC) was modified by immersing it in different solutions, including mixed acid solutions, ammonia solutions, KMnO₄ solutions and surfactant solutions, to improve its adsorption efficiency of endocrine disrupting compounds. Changes in the surface chemistry and the porous structure were assessed by specific surface area and porosity analyser, SEM, FT-IR, and Boehm titration. The best modification method of activated carbon was determined by static adsorption experiments, and the adsorption mechanism of modified activated carbon was discussed. The results showed that KMnO₄ modified activated carbon (AC-K) had the best contaminant adsorption performance. The removal rates of DBP, Atrazine and SMZ by AC-K were 94.5%, 93.8% and 95.5%, respectively, and the adsorption process was in accordance with second-order kinetic equation and D-R model. From the calculated results of these models, we found that the adsorption rates of AC-K on the target pollutants were significantly accelerated, and the secondary adsorption rate constant of Atrazine was 1.75 times than that of AC. The theoretical saturated adsorption capacity of DBP, Atrazine and SMZ by AC-K were improved by 42.2%, 629% and 122%, respectively, compared with those before modification. The adsorption mechanism of activated carbon was transformed from physical adsorption into ion exchange adsorption, after modified by KMnO_4.