Application of in-plasma catalysis and post-plasma catalysis for methane partial oxidation to methanol over a Fe2O3-CuO/γ-Al2O3 catalyst

Methane partial oxidation to methanol (MPOM) using dielectric barrier discharge over a Fe2O3-CuO/γ-Al2O3 catalyst was performed. The multicomponent catalyst was combined with plasma in two different configurations, i.e., in-plasma catalysis (IPC) and post-plasma catalysis (PPC). It was found that the catalytic performance of the catalysts for MPOM was strongly dependent on the hybrid configuration. A better synergistic performance of plasma and catalysis was achieved in the IPC configuration, but the catalysts packed in the discharge zone showed lower stability than those connected to the discharge zone in sequence. Active species, such as ozone, atomic oxygen and methyl radicals, were produced from the plasma-catalysis process, and made a major contribution to methanol synthesis. These active species were identified by the means of in situ optical emission spectra, ozone measurement and FT-IR spectra. It was confirmed that the amount of active species in the IPC system was greater than that in the PPC system. The results of TG, XRD, and N2 adsorption-desorption revealed that carbon deposition on the spent catalyst surface was responsible for the catalyst deactivation in the IPC configuration.