Catalytic degradation of ortho‐chlorophenol using activated carbon modified by different methods

Abstract

The performance of activated carbon (AC) modified by different methods was compared for its catalytic degradation of ortho‐chlorophenol (o‐CP). For the chemically treated AC, the catalytic effect of AC–NH3∙H2O was superior to the other catalysts examined, having an o‐CP removal efficiency of 82.2% at 330 °C. For the metal‐modified catalysts, AC–V and AC–Co showed similar removal performances of 93.2% at 330 °C. N2 adsorption‐desorption isotherms, Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), and gas chromatography—mass spectrometry (GC‐MS) analyses were used to characterize the reaction products, and different reaction mechanisms were proposed for both AC–NH3∙H2O and AC–V according to the results. Complete oxidative degradation of o‐CP was achieved by AC–V, with AC–NH3∙H2O leading to the formation of additional dioxins. It can be deduced that a risk of dioxin synthesis and escape during the regeneration process is possible when nitrogen‐modified carbon is used in selective catalytic reduction (SCR) denitrification reactions, especially in the presence of chlorine atoms, benzene rings, and oxygen.