Xylene is a typical petrochemical industry pollutant. The fate of xylene spilled into soil was investigated in laboratory-scale batch and column experiments. The results show that free xylene in the soil evaporated quickly (7.2–10.4 mg h⁻¹), but any fraction adsorbed onto the soil particles evaporated much more slowly (2.3–2.4 mg h⁻¹). The retention of xylene in the soil was mainly controlled by its adsorption onto the soil minerals. The adsorption was best described using a pseudo-second-order kinetic model and Langmuir model. Adsorption up to 530 mg kg⁻¹ was observed, and minerals such as quartz and kaolinite were the key adsorbents. Adsorption of xylene was promoted by the presence of dissolved organics up to about 50 mg L⁻¹, but it was significantly inhibited by cobalt-bearing compounds which are often used as catalysts in the petrochemical industry. The release of xylene from soil would be facilitated by intense rainfall and cobalt-bearing compounds but would be inhibited with the increase of rainwater acidity. This study reveals the environmental behavior of xylene in soil and provides scientific guidance for pollution control and risk assessment of BTEX contaminated sites.

二甲苯是一种典型的石化工业污染物。在实验室规模的批次和柱实验中研究了泄漏到土壤中的二甲苯的命运。结果表明，土壤中的游离二甲苯蒸发迅速（7.2-10.4 mg h ^-1），但吸附在土壤颗粒上的任何部分蒸发得更慢（2.3-2.4 mg h ^-1）。二甲苯在土壤中的保留主要受其吸附在土壤矿物质上的控制。使用准二级动力学模型和朗缪尔模型最好地描述吸附。观察到高达 530 mg kg ^-1的吸附，石英和高岭石等矿物是关键吸附剂。高达约 50 mg L ^{-1的溶解有机物的存在促进了二甲苯的吸附}, 但它受到石化工业中常用作催化剂的含钴化合物的显着抑制。强降雨和含钴化合物会促进二甲苯从土壤中的释放，但会随着雨水酸度的增加而受到抑制。本研究揭示了二甲苯在土壤中的环境行为，为BTEX污染场地的污染控制和风险评估提供科学指导。