Biosynthesized iron-based nanoparticles used as a heterogeneous catalyst for the removal of 2,4-dichlorophenol

•Green synthesis of Fe NPs using Euphorbia cochinchensis leaves extracts.•The removal efficiency of 2,4-DCP reached up to 64.0% using FeNPs.•The removing 2,4-DCP via pre-adsorption/Fenton-like oxidation.•The proposed method is one of potential techniques for the nanoremediation.

Iron-based nanoparticles (Fe NPs) synthesized by Euphorbia cochinchensis leaves extracts and used for degradation of 2,4-dichlorophenol (2,4-DCP) were investigated. The TEM image indicated Fe NPs were spherical and uniformly dispersed particles with a diameter of about 100 nm. The XPS results indicated Fe NPs consisted mainly of Fe(III), Fe(II), iron oxide and hydroxide. Results confirmed that the efficiency to remove 2,4-DCP was 20.6% by adsorption. The efficiency increased to 51.9% when Fe NPs were used as Fenton-like catalyst in the presence of H2O2. However, the removal efficiency of 2,4-DCP reached up to 64.0% when adsorption and Fenton-like oxidation were integrated. The kinetic data fitted well with the pseudo-second-order kinetic model of adsorption, while the Fenton-like process fitted the pseudo-first-order oxidation model. Furthermore, the degraded products were detected by gas chromatography mass spectrometry (GC-MS) to verify the mechanisms of degradation. It is concluded that removal of 2,4-DCP via adsorption/Fenton-like oxidation.