A research group has introduced an innovative plasma-catalytic method for transforming carbon dioxide (CO2) into methanol at standard room temperature and pressure. This advancement tackles the challenges associated with conventional thermal catalysis, which typically necessitates elevated temperatures and pressures, leading to inefficient CO2 conversion and low methanol production.
Scientists at the University of Liverpool have reached a crucial achievement in the transformation of carbon dioxide (CO2) into useful fuels and chemicals, representing a significant move toward a sustainable net-zero economy.
In a study published in the journal Chem, the researchers describe their groundbreaking plasma-catalytic technique for the hydrogenation of CO2 to methanol, which operates at ambient temperature and atmospheric pressure.
This innovation overcomes the drawbacks of traditional thermal catalysis, which generally requires high temperatures and pressures, often resulting in poor CO2 conversion rates and minimal methanol production.
The new method employs a bimetallic Ni-Co catalyst within a non-thermal plasma reactor, achieving an impressive 46% selectivity for methanol in a single pass, as well as a 24% CO2 conversion at 35 °C and 0.1 MPa.
Non-thermal plasma, which is an ionized gas rich in energetic electrons and reactive agents, is capable of breaking strong chemical bonds in inert molecules such as CO2, allowing chemical reactions to take place under mild conditions.
Moreover, plasma-based modular systems can be switched on and off instantly, providing significant flexibility to utilize intermittent renewable electricity for localized production of fuels and chemicals.
Professor Xin Tu, Chair in Plasma Catalysis at the University of Liverpool, mentioned: “Our findings show that plasma catalysis offers a flexible and decentralized method for the hydrogenation of CO2 to methanol under normal conditions. Our recent techno-economic evaluation indicates that this process could greatly lower capital costs in comparison to traditional thermal catalytic methods, creating a viable pathway for harnessing renewable energy sources in synthetic fuel production.”
In situ plasma-coupled Fourier transform infrared (FTIR) analysis and density functional theory (DFT) computations have shown that the bimetallic Ni-Co interface serves as the main active site for methanol production, where CO2 adsorption and hydrogenation occur through the Eley-Rideal (E-R) mechanism, leading to various intermediates. Both the formate and carboxyl pathways are essential for methanol generation, while the reverse water-gas shift (RWGS) and CO hydrogenation routes were found to be less advantageous on the Ni-Co sites. The careful optimization of Ni-Co sites in bimetallic catalysts offers significant potential to tailor the significance of each reaction pathway by favorably influencing the adsorption of CO2 molecules at the bimetallic interfaces, thus effectively adjusting product distribution.
This study highlights the considerable promise of plasma catalysis as a developing electrification technology for sustainable CO2 conversion and fuel production. Conducting these reactions under ambient conditions with a modular and scalable plasma system presents a compelling alternative for the chemical industry.
Additionally, plasma systems can be operated using intermittent renewable electricity, improving the practicality of decentralized production of fuels and chemicals.
This groundbreaking research represents a major advance in catalytic CO2 conversion and paves the way for future studies and industrial uses aimed at addressing the challenges of creating a sustainable future.
The research team at the University of Liverpool is a frontrunner in plasma catalysis, having made significant strides in converting CO2 to various fuels and chemicals. They have also developed promising methods for CO2 methanation and a single-step biogas conversion process to methanol, filing three PCT patents in this field.
