Investigation of cyclohexane catalytic degradation driven by N atoms from N₂ discharges

Abstract

The effect of N2 discharge products on cyclohexane degradation over MnO2/γ-Al2O3 catalyst has been evaluated by feeding N2 discharge products to the catalyst using a specially designed dielectric barrier discharge reactor. At reaction temperature of 100 o°C, the cyclohexane conversion increased from 2.46% (without N2 discharge products) to 26.3% (with N2 discharge products). N and O-containing by-product (3, 4-dehydroproline) was found on the catalyst surface using gas chromatograph-mass spectrometry identification, in which C=N-–C and C=N-–H bonds were also confirmed from X-ray photoelectron spectroscopy analysis results. Operando analysis results using diffuse reflectance infrared Fourier transform spectroscopy revealed that N atoms can react with surface H2O possibly to NH and OH reactive species, those species which have reactivities to promote CO oxidation to CO2. Mechanism of N-atom driven cyclohexane degradation to CO and CO2 is proposed.