Migration rules of petroleum pollutants in water and soil: a review

In the process of petroleum exploitation, transportation and use, soil, and groundwater are easily polluted. Petroleum pollutants such as petroleum hydrocarbons, benzene, toluene, ethylbenzene, and xylene (BTEX), and polycyclic aromatic hydrocarbons (PAHs), migrate under the action of the environment, widening the range of pollution and threatening the health of animals and humans. To better support risk assessment and pollution control for oil spills, a good understanding of oil transport in the environment is required. This review aims to discuss the migration of petroleum pollutants in soil and water. This article begins with the analysis of the typical petroleum pollutants and their components. The study focuses on systematically describing the occurrence and spatial distribution characteristics of petroleum pollutants in water and soil, the migration mechanism and the numerical model to simulate the migration of petroleum pollutants. The transport processes of petroleum hydrocarbon pollutants such as adsorption, desorption, and biological action are also introduced in detail. The limitations of existing research and the optimization of the migration model are pointed out.