Reductive dechlorination of 2,4-dichlorophenol by Pd/Fe nanoparticles prepared in the presence of ultrasonic irradiation

► Pd/Fe nanoparticles were prepared by using ultrasound strengthened liquid phase. ► Ultrasonic irradiation can enhance disparity and avoid agglomeration of nano-Pd/Fe. ► Pd/Fe nanoparticles showed high dechlorination efficiency of 2,4-DCP. ► Factors of reductive dechlorination by nano-Pd/Fe were studied.