Title : Recent advances in non-thermal plasma enhanced catalysis for CO2 conversion and SO2 reduction
Non-thermal plasma can activate various molecules that are thermally difficult to activate at low (or ambient) temperatures. Recent advances in non-thermal plasma-enhanced catalysis has made it possible to conduct difficult reactions at ambient temperatures for activating molecules such as carbon dioxide (CO2) and sulphur dioxide (SO2). Integrating non-thermal plasma such as dielectric barrier discharge (DBD) plasma with heterogeneous catalysts can enable the conversion of CO2 to chemicals and fuels (C2+ hydrocarbons, or C2+ alcohols) with H2 or H2O. Such a DBD plasma-metal sulfide catalyst combination can also allow direct reduction of SO2 into elemental sulphur in a single stage at low temperature. On the other hand, determining the origin of the plasma–catalysis synergy and reaction mechanisms in non-thermal plasma-enhanced catalytic reactions remains challenging because complex processes take place when coupling plasma with heterogeneous catalysts. We have designed a probe reaction to decouple plasma-induced surface reactions from plasma-phase reactions in SO2 reduction to S. The qualitative and quantitative analyses reveal a new Eley-Rideal reaction between plasma-generated atomic hydrogen in the gas phase and strongly adsorbed SO2 over alumina, a reaction that is not thermally feasible. Both catalytic advances and mechanistic insights will be discussed.
- Recent advances in plasma-catalysis could allow people to find alternate ways to improve energy efficiency and tailor the reaction pathways in chemical processes.
- This keynote presentation could allow other researchers and (post)graduate research students to expand their research approach in catalysis, energy, CO2 conversion and chemical processing research.
- The new approaches presented provide a practical solution to longstanding problem of acid gas SO2 conversion to elemental sulfur and CO2 conversion to value-added products.
- Advances in this area could enable breakthroughs in plasma catalysis for energy, fuels and CO2 utilization.