Effect of gas flow rate and discharge volume on CO₂ methanation with plasma catalysis

Abstract

CO2 methanation can be a key technology for realizing a sustainable society. CH4 is used as an energy carrier and raw material for chemical products, thereby contributing to the reduction of CO2 emissions. Methanation with plasma catalysis lower the process temperature, which can improve the throughput and stability. In this study, we investigated the effect of the gas flow rate and the discharge volume on CO2 methanation, using a low- pressure CCP reactor. Higher gas flow rates can increase the rate of CO2 throughput, but the CH4 selectivity decreases owing to the reduced transportation rate of the reactants to the catalyst surface. Increasing the discharge volume is effective in improving the transportation rate. This study suggested that the structure of the reactor significantly affect the CH4 generation rate.

Influence of humidity on the plasma‐assisted CO2 conversion

“…Moreover, the use of a low gas flow rate has been observed as a contributing factor to higher CO 2 conversion rates in previous research. [ 26,27 ]…”

“…Moreover, the use of a low gas flow rate has been observed as a contributing factor to higher CO 2 conversion rates in previous research. [26,27] In our plasma reactor, the gas flow rate does not play a prominent role since we halt gas flow during plasma irradiation. Instead, our 2D simulations have shown the formation of a reverse vortex, which concentrates CO 2 gas near the plasma electrode region.…”

“…[26] Similarly, in another investigation using a low-pressure capacitively coupled plasma reactor, CO 2 conversion decreased from 65% to 35% as the flow rate increased (ranging from 0.5 to 3.0 sccm). [27] The aforementioned studies highlight the existing gap in technology when it comes to achieving high CO 2 conversion rates with low energy costs, especially in the absence of catalysts. In our recent research, we have made significant progress by utilizing streamer plasma for the conversion of both CO 2 and N 2 into valuable plant nutrients.…”

“…[ 26 ] Similarly, in another investigation using a low‐pressure capacitively coupled plasma reactor, CO 2 conversion decreased from 65% to 35% as the flow rate increased (ranging from 0.5 to 3.0 sccm). [ 27 ]…”

Unraveling Temperature-Dependent Plasma-Catalyzed CO2 Hydrogenation

“…In recent years, there has been growing interest in using NTP technology for chemical and fuel synthesis. ,,,,− NTPs are capable of generating highly reactive species and electrons that facilitate thermodynamically unfavorable reactions under mild conditions. When combined with heterogeneous catalysis, NTPs can create a synergistic effect that enhances reaction performance. − This combination alters the properties of the catalyst, reduces its activation barrier, and improves the overall energy efficiency and product selectivity of the plasma-catalytic process. − Additionally, the fast on/off switching of plasma processes, makes them suitable for integration with irregular and intermittent renewable energy sources, such as solar and wind power. , According to the literature, nickel and cobalt-based catalysts have been extensively investigated for CO 2 methanation due to their low cost and comparable catalytic performance to noble metal-based catalysts. ,− These catalysts have been shown to be effective in promoting the CO 2 methanation reaction at low temperatures and pressures.…”