Acetaldehyde is a multipurpose chemical found in everything from perfumes to plastics. It is produced using old petrochemical-based methods, but growing environmental problems are forcing the chemical industry to find more greener production lines.
In a promising step forward, a team of researchers has developed a novel copper-based catalyst that can effectively convert carbon dioxide (CO2) into acetaldehyde. This catalyst offers a greener alternative to current production methods.
Currently, the most widely used method for producing acetaldehyde is the “Wacker process,” which involves ethylene—a compound derived from oil and natural gas—and strong acids like hydrochloric acid. This process contributes to high carbon emissions and relies heavily on non-renewable resources, making it unsustainable in the long term.
In response to these challenges, scientists have been investigating the electrochemical reduction of CO2 as a way to reduce greenhouse gas emissions and produce valuable chemicals. This method could address two environmental issues simultaneously by using CO2—a waste product that exacerbates global warming.
The research team, led by Cedric David Koolen at EPFL, Jack K. Pedersen at the University of Copenhagen, and Wen Luo at Shanghai University, has developed a copper-based catalyst capable of selectively converting CO2 into acetaldehyde with an outstanding efficiency of 92%. Their findings could replace the Wacker process and offer a cleaner, more sustainable method for acetaldehyde production.
Copper catalysts work better when they gain and lose oxygen atoms
“The Wacker process has remained largely unchanged for the past 60 years. It was time for a green breakthrough,” said Koolen. The new catalyst, which is scalable and cost-effective, shows promise for industrial applications and could revolutionize the chemical industry.
The catalyst’s design is the key to the team’s success. They used spark ablation to synthesize copper particles- measuring just 1.6 nanometers in size. Using this method, the team could control the size and structure of the copper clusters with remarkable precision. In this technique, copper electrodes vaporize in an inert gas environment.
Once synthesized, the copper clusters were immobilized on carbon supports to create a stable, reusable catalyst. Testing the catalyst’s performance in the lab, the team achieved an astonishing 92% selectivity for acetaldehyde, even at low voltages—an important factor for energy efficiency.
The catalyst also demonstrated exceptional stability. In a 30-hour stress test, the catalyst maintained high efficiency over multiple cycles, a critical factor for industrial applications. The copper particles retained their metallic nature throughout the reaction, contributing to the catalyst’s longevity.
“What was really surprising to us was that the copper remained metallic, even after exposure to air,” said co-lead author Wen Luo. “Copper usually oxidizes quickly, especially at such small scales. But in our case, an oxide shell formed around the cluster, protecting the core from further oxidation, which explains the material’s recyclability.”
Computational simulations revealed that the copper clusters’ specific atomic configuration facilitates the bonding of CO2 molecules in a way that favors the formation of acetaldehyde over other by-products like ethanol or methane. This targeted selectivity is one of the key reasons the catalyst works so efficiently.
“Our process can be applied to a wide range of catalytic systems,” said co-lead author Jack K. Pedersen. “With our computational framework, we can quickly screen catalysts for promising characteristics and directly test them in the lab—much faster than traditional methods.”
This breakthrough offers a sustainable path forward for producing acetaldehyde, a critical building block for many other chemicals used in pharmaceuticals, agriculture, and beyond. If scaled up, the new catalyst could reduce the chemical industry’s reliance on petrochemicals and reduce CO2 emissions, contributing to global climate goals.
The research marks a significant milestone in the search for greener, more efficient industrial processes. With further development, this copper-based catalyst could help transform the way chemicals are produced, ushering in a new era of green chemistry.
As the world moves toward more sustainable solutions, the electrochemical reduction of CO2 into acetaldehyde may play a crucial role in reducing the environmental impact of industries that rely on this essential chemical.
Journal Reference:
- Koolen, C. D., Pedersen, J. K., Zijlstra, B., Winzely, M., Zhang, J., Pfeiffer, T. V., Vrijburg, W., Li, M., Agarwal, A., Akbari, Z., Kuddusi, Y., Herranz, J., Safonova, O. V., Schmidt-Ott, A., Luo, W., Züttel, A. Scalable synthesis of Cu cluster catalysts via spark ablation for the highly selective electrochemical conversion of CO2 to acetaldehyde. Nature Synthesis 03 January 2025. DOI: 10.1038/s44160-024-00705-3
Source: Tech Explorist
