Ma Yan, Wu Xinyi, Wang Tong, Zhou Shengkun, Cui Biying, Sha Haoqun, Lv Bowen
School of Chemical and Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, People's Republic of China.
Beijing Solid Waste Treatment Co., Ltd, Beijing, 100101, People's Republic of China.
Environ Sci Pollut Res Int. 2023 Mar;30(14):39871-39882. doi: 10.1007/s11356-022-25096-w. Epub 2023 Jan 5.
Complexes formed by organic matter and clay minerals, which are active components of soil systems, play an important role in the migration and transformation of pollutants in nature. In this study, humic-acid-montmorillonite (HA-MT) and humic-acid-kaolin (HA-KL) complexes were prepared, and their structures before and after the adsorption of aniline were analyzed. The aniline adsorption-desorption characteristics of complexes with different clay minerals and varying HA contents were explored using the static adsorption-desorption equilibrium method. Compared with the pristine clay minerals, the flaky and porous structure of the complexes and the aromaticity were enhanced. The adsorption of aniline on the different clay mineral complexes was nonlinear, and the adsorption capacity increased with increasing HA content. Additionally, the adsorption capacity of HA-MT was higher than that of HA-KL. After adsorption, the specific surface area of the complexes decreased, the surfaces became more complicated, and the aromaticity decreased because aniline is primarily adsorption onto the complexes via aromatic rings. Aniline was adsorbed onto the complexes via spontaneous exothermic physical adsorption. The amount of aniline desorbed from the complexes increased with increasing HA content, and a lag in desorption was observed, with a greater lag for HA-KL than for HA-MT.
由有机质和粘土矿物形成的络合物是土壤系统的活性成分，在自然界中污染物的迁移和转化过程中起着重要作用。本研究制备了腐殖酸-蒙脱石（HA-MT）和腐殖酸-高岭土（HA-KL）络合物，并分析了其吸附苯胺前后的结构。采用静态吸附-解吸平衡法探究了不同粘土矿物和不同腐殖酸含量的络合物对苯胺的吸附-解吸特性。与原始粘土矿物相比，络合物的片状和多孔结构以及芳香性增强。苯胺在不同粘土矿物络合物上的吸附是非线性的，吸附量随腐殖酸含量的增加而增加。此外，HA-MT的吸附量高于HA-KL。吸附后，络合物的比表面积减小，表面变得更加复杂，芳香性降低，因为苯胺主要通过芳香环吸附在络合物上。苯胺通过自发放热的物理吸附作用吸附在络合物上。从络合物上解吸的苯胺量随腐殖酸含量的增加而增加，且观察到解吸存在滞后现象，HA-KL的滞后现象比HA-MT更明显。
