Electrochemical conversion of methane to ethylene in a solid oxide electrolyzer

Area of Science:

• Catalysis
• Electrochemistry
• Chemical Engineering

Background:

• Direct conversion of methane to ethylene is hindered by low selectivity, catalyst deactivation via carbon deposition, and instability.
• Developing efficient and stable catalysts for methane conversion remains a significant challenge in chemical synthesis.

Purpose of the Study:

• To demonstrate a novel in situ electrochemical oxidation process for converting methane to ethylene.
• To enhance catalyst stability and coking resistance at high temperatures for methane conversion.

Main Methods:

• Utilizing a solid oxide electrolyzer operating at ambient pressure and 850°C.
• Employing a porous electrode scaffold with an in situ-grown metal/oxide interface.

Main Results:

• Achieved a C2 product selectivity of 81.2% and a C2 product concentration of 16.7% (12.1% ethylene, 4.6% ethane).
• Reached a methane conversion of 41% in the initial pass.
• Demonstrated catalyst stability with no degradation after 100 hours of operation and 10 redox cycles.

Conclusions:

• The developed electrochemical process offers a reliable method for converting methane to valuable chemicals like ethylene.
• The in situ metal/oxide interface strategy significantly improves catalyst performance and longevity under demanding conditions.