Degradation of p-chloroaniline by FeO3-xH3-2x/Fe0 in the presence of persulfate in aqueous solution

Sulfate radical based advanced oxidation processes are promising techniques for the removal of organic compounds in aqueous solutions. In this study, FeO3-xH3-2x/Fe-0 catalyst was prepared and used to activate persulfate (S2O82-) for the degradation of p-chloroaniline (PCA). The results showed that nearly complete degradation of PCA was observed within 1 h in the persulfate-FeO3-xH3-2x/Fe-0 system under the following optimized reaction conditions: PCA concentration 0.05 mM, FeO3-xH3-2x/Fe-0 1 g L-1, persulfate 2.5 mM and pH 7.0. The PCA degradation was higher under acidic conditions when compared to alkaline conditions. A complete removal of the added PCA (0.05 mM) was achieved within 5 min with the addition of 2.5 mM persulfate and 1 g L-1 FeO3-xH3-2x/Fe-0 at pH 3.0. FeO3-xH3-2x/Fe-0 catalyst was prepared by the calcination of Fe-0 at 200 degrees C. The morphology of the catalyst was investigated with X-ray diffraction patterns (XRD), Scanning electron microscopy (SEM) and Fourier transform infrared spectra (FTIR). The results demonstrated that the catalyst surface was mainly composed of hematite gamma-Fe2O3 and goethite (alpha-FeOOH).