The experimental and theoretical remediation of polycyclic aromatic hydrocarbons (PAHs) contaminated soil has been investigated by superheated water extraction. In this study, effect of three parameters on extraction efficiency has been investigated including the extraction temperature, time, and flow rate. Water temperature was varied between 100 and 165 degrees C, extraction time between 5 and 15 min, and flow rate between 1 and 2.5 mL/min. Specifically, this study examines the effectiveness of different parameters on the removal of phenanthrene (a representative PAH) from the soils. More than 83% extraction of the phenanthrene from contaminated soil was observed at 165 degrees C for 15 min and flow rate of 1.75 mL/min at a constant pressure of 20 bar. Also, a mathematical model for soil remediation was developed which predicted the experimental data very well. Both the model and experimental results suggested that the extraction efficiency was extremely dependent on extraction temperature and time. (C) 2015 Elsevier B.V. All rights reserved.