Partial Oxidation of Methane with Yttria-stabilized Zirconia Catalyst in a Dielectric Barrier Discharge

Abstract

Yttria-stabilized zirconia (YSZ) has been used and studied as a catalyst material for the direct partial oxidation of methane into methanol using dielectric barrier discharge (DBD). The methanol synthesis process occurred at ambient temperature and atmospheric pressure. It showed that YSZ has an activity to increase the production of methanol. It was twice as high in methanol selectivity than non-catalytic plasma process. The YSZ catalyst also showed better performance compared to other common catalyst supports, e.g., carbon, Al 2 O 3 , TiO 2 , and SiO 2 . Instead of methanol, the reaction products of plasma reactions were dominated by H 2 , CO, CO 2 , C 2 , and water. The optimum methanol selectivity reached 23% when Ni metal was doped over YSZ.

The kinetic studies of direct methane oxidation to methanol in the plasma process

“…In order to reduce the production of CO and CO 2 , some other researches were conducted at higher pressure in liquid phase [3] and the catalyst was employed . Especially, we also conducted research on the use of catalyst,and some results were published [8][9][10] .…”

“…Moreover, there is a possibility to increase the production of methanol from partial oxidation of methane by controlling the reaction mechanism which can be done by some catalysts [8][9][10] . The performance of direct methane oxidation conversion to methanol in both thermal and plasma processes has been studied experimentally.…”

Selective oxidation of CH4 to CH3OH through plasma catalysis: Insights from catalyst characterization and chemical kinetics modelling

“…[22][23][24][25][26][27] Generally, the gas temperature in NTP remains near room temperature, while the generated electrons exhibit a typical temperature of 1-10 eV (~ 10 4 -10 5 K), which is sufficient to activate feed gas molecules (e.g., CH4 and O2) into reactive species, including radicals, excited atoms and molecules, and ions. Several scientists have studied SOMTM by O2 through plasma and/or plasma catalysis, [28][29][30][31][32][33][34][35][36] but only a few have reported satisfying CH3OH selectivity. Nozaki applied a microplasma and obtained a CH4 conversion to synthetic fuels with maximum organic liquid selectivity of 70 % without catalysts (plasma alone), [28] but the CH3OH selectivity was below 15 %.…”

“…Indarto realized CH3OH synthesis with optimum selectivity of 23 % using a dielectric barrier discharge (DBD) reactor with Ni metal doped over yttria-stabilized zirconia as catalyst. [29] Chawdhury used a packed bed DBD reactor, in which glass beads provided an optimal CH3OH selectivity of 35.4 %, [30] while further work reported the best CH3OH selectivity of 37 % using CuO/γ-Al2O3 catalyst. [31] Recently, Cu/γ-Al2O3, Ni/γ-Al2O3 and Fe/γ-Al2O3 catalysts were compared for plasma-catalytic methane to value-added liquid fuels and chemicals, in which the highest liquid oxygenate (~ 71%) were achieved, with Fe/γ-Al2O3 catalyst exhibited highest methanol selectivity of 36.0% among three different catalysts.…”

“…As mentioned above, in plasma alone, we achieved 42 % CH3OH selectivity (Figure 1A), which is much better than most results in literature. [28][29][30][31][32][33][34][35][36] To explain this result, we performed chemical kinetics modelling of CH4/O2 DBD plasma using…”