Researchers reveal elusive bottleneck holding back global efforts to convert carbon dioxide waste into usable products

Think of it as nanoscale recycling: a tantalizing electrochemical process that can harvest carbon before it becomes air pollution and restructure it into components of everyday products.

The drive to capture airborne carbon dioxide from industrial waste and turn it into fuel and plastic is gaining momentum after a team of researchers based at McMaster University, in collaboration with experts in computational chemistry from the Danish Technical University in Copenhagen, have discovered precisely how the process works and where it goes wrong.

Their work is published in the journal Natural communications.

Researchers sought to understand why synthetic materials that catalyze and convert carbon dioxide break down too quickly for the process to be practical on an industrial level.

Using extremely powerful magnification equipment at the Canadian Center for Electron Microscopy (CCEM), based on the McMaster campus, the researchers were able to capture the chemical reaction at the nanoscale (billionths of a meter), allowing them to ‘study both the conversion process and understand how the catalyst breaks down under operating conditions.

Lead author Ahmed Abdellah spent years developing the techniques to observe the process, using an electrochemical reactor small enough to operate under the center’s electron microscopes.

“It’s exciting for us that this is the first time that someone can look at both the shapes of these structures and their crystal structures, to see how they evolve on the nanoscale,” says Abdellah, a former doctoral student. student in Drew Higgins’ chemical engineering lab and now a postdoctoral fellow at CCEM.

Higgins, a corresponding author on the paper, hopes the new information will aid the global effort to reduce carbon pollution by removing carbon dioxide from waste streams and recycling it to create useful products that would otherwise be produced from fossil fuels.

“What we found is that catalysts capable of converting carbon dioxide into fuels and chemicals restructure quite quickly under operating conditions. Their structures and properties change, before our eyes,” says Higgins . “This determines how effective they are at converting carbon dioxide and how long they last. The catalysts eventually degrade and stop working and we want to know why they do that and how they do it so we can develop strategies to improve their operational life.”

Abdellah, Higgins and their colleagues hope that they and other researchers around the world can use the research results described in the new paper to extend the life of reactive materials and catalyze the process more efficiently, allowing for the laboratory process to be extended. for commercial use.

Industries such as cement manufacturing, brewing and distillation, as well as chemical refineries, produce large volumes of easily recoverable carbon dioxide, says Higgins, making them likely prime targets for deployment of the technology once that it will have been improved to the point where it will be commercially viable. .

Other less concentrated forms of CO₂ in industrial waste would come next.

While it’s a long way off today, Higgins says it’s possible the same technology could become efficient and stable enough to extract carbon dioxide from ambient air as a “feedstock” for fuel and chemicals. useful.

“We’re still a long way off, but progress has been very rapid in this area of ​​research and development over the last five years,” says Higgins. “Ten years ago, people weren’t thinking about this type of conversion, but now we’re starting to see promise. Efficiency and sustainability, however, are simply not high enough yet. Once these bottlenecks are removed, this idea can really take off.”