Influence of soil organic components on the aniline adsorption mechanism

Hydrophobic organic compounds (HOCs) exhibit strong hydrophobicity and low water solubility and are readily adsorbed into soil, which is a complex organic compound. In this study, the adsorption effect and mechanism of 10 soil organic matter components on HOCs (represented by aniline) are studied. Furthermore, a chemical extraction method is used to extract different soil organic components to study their properties and functional groups. The adsorption kinetic experiment is conducted to determine the equilibrium time of aniline. The isothermal adsorption experiment is conducted to determine the isothermal adsorption model of aniline and explore its characteristics. Results show that different components have various physical and chemical properties. The pseudo-quadratic kinetic model fitted well with experimental data, indicating that the adsorption of aniline reached equilibrium within 24 h. The Freundlich model fits the isotherm adsorption data of aniline, revealing that the adsorption capacity is significantly positively correlated with the organic carbon content and specific surface area. This study shows that humic acid 2 has the best adsorption capacity for aniline. This study enables the prediction of environmental risks posed by HOCs such as aniline.