Catalytic Degradation of Ortho-Chlorophenol Using Activated Carbon Modified by Different Methods

Abstract

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-NH 3 ·H 2 O 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. N 2 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-NH 3 ·H 2 O and AC-V according to the results. Complete oxidative degradation of o-CP was achieved by AC-V, with AC-NH 3 ·H 2 O 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.

Insight into the Transformation Behaviors of Dioxins from Sintering Flue Gas in the Cyclic Thermal Regeneration by the V2O5/AC Catalyst-sorbent

“…39 The deconvolution spectra of V 2p illustrated in Figure 3b included two characteristic peaks for V 4+ sited at 516.5 eV and V 5+ at 517.3 eV. 40,41 The relative content of V 5+ decreased from 91.79% in the fresh sample to 75.68% in RE-4, implying the reduction of V 5+ to V 4+ by adsorbed intermediates. The decrease of V 5+ was possibly the main factor for the decline in the DBF removal activities of regenerated catalysts.…”

Catalysts for Oxidative Destruction of Volatile Organic Compounds

“…Zheng et al studied a range of activated carbon catalysts, modified by various treatments, for the oxidative degradation of ortho-chlorophenol [4]. Ortho-chlorophenol was selected for study as it is an appropriate model for dioxins, which are highly toxic and produced from many incineration and industrial processes.…”