Syngas production by high temperature steam/CO2 coelectrolysis using solid oxide electrolysis cells.

Area of Science:

• Chemical Engineering
• Electrochemistry
• Materials Science

Background:

• Solid oxide electrolysis cells (SOECs) offer a sustainable pathway for syngas production.
• High-temperature (HT) coelectrolysis of steam and CO2 is a promising alternative to fossil fuel-based methods.
• Minimizing greenhouse gas emissions is crucial for future energy systems.

Purpose of the Study:

• To investigate the reaction characteristics and syngas composition of HT steam/CO2 coelectrolysis.
• To analyze the influence of operating conditions on coelectrolysis performance.
• To assess the potential for controlling syngas output via process parameters.

Main Methods:

• Systematic study of HT steam/CO2 coelectrolysis at 800 °C using commercial SOECs.
• Varying inlet gas compositions and electrolysis current densities.
• Analysis of outlet syngas composition and reaction characteristics.

Main Results:

• HT steam/CO2 coelectrolysis performance is comparable to steam electrolysis and superior to CO2 electrolysis.
• The reverse water-gas shift reaction significantly contributes to CO formation.
• Outlet syngas composition is highly sensitive to operating conditions.
• Maximum steam and CO2 utilizations of 77% and 76% were achieved at 1.0 A cm(-2) with specific inlet gas mixture.

Conclusions:

• HT steam/CO2 coelectrolysis is an active and viable process for clean syngas production.
• Process parameters offer effective control over the outlet syngas composition.
• This technology presents a flexible route for producing syngas without fossil fuels or emissions.