초록 |
In this study, oxidative coupling of methane (OCM) was carried out to produce C2 or C3 hydrocarbons directly from methane in a plasma-catalysis hybrid system. Since catalyst only reaction requires high temperature above 700 °C, dielectric barrier discharge (DBD) plasma was applied as plasma source to lower the reaction temperature. Among various supports, only SiO2 showed the higher yield than plasma only reaction when combined with DBD plasma, which led us to focus on the SiO2-based catalyst. By screening diverse metal supported on SiO2 catalysts, it was found that Ag/SiO2 demonstrated the highest C2+ hydrocarbon yield of about 9.7% at 385 °C. However, during the stability test with time-on-stream, Ag/SiO2 catalyst with plasma became deactivated due to coking. Therefore, regeneration process was introduced after OCM reaction. As a result, plasma regeneration at 378 °C successfully recovered the activity without sintering of Ag, which occurred upon thermal regeneration. |