An international team of researchers has developed a new way to convert carbon dioxide (CO₂) from factory exhaust directly into a valuable fuel ingredient without first separating or purifying the gas.
The breakthrough could make carbon capture technologies simpler, cheaper, and more practical for heavy industries that produce large amounts of greenhouse gas emissions.
The study, led by researchers from the Université de Montpellier in France and the University of Adelaide in Australia, was published in Nature Communications.
Many industries, including steel production, cement manufacturing, chemical plants, power stations, and alumina refining, release large amounts of CO₂ in their exhaust gases, also known as flue gas.
However, this gas is far from pure. It contains relatively low levels of CO₂ mixed with much larger amounts of nitrogen, oxygen, and other gases.
These impurities have made it difficult to convert captured CO₂ into useful products. Most existing technologies require the CO₂ to be separated and purified before it can be used, a process that consumes large amounts of energy and adds significant cost.
The researchers have now developed an alternative approach that avoids this expensive purification step. Their system uses a specially designed organic liquid that allows CO₂ to react efficiently even when it is mixed with other gases found in industrial exhaust.
The liquid works by reducing hydrogen bonding, which normally encourages unwanted chemical reactions. By limiting these side reactions, the system directs nearly all of the captured CO₂ into producing carbon monoxide (CO).
Although carbon monoxide is toxic, it is also an important industrial chemical. It serves as a key building block for producing synthetic fuels, plastics, and many other valuable chemicals.
When tested using a simulated industrial exhaust containing 15% CO₂ and 8% oxygen, the system converted almost all of the CO₂ into carbon monoxide with extremely high selectivity.
The researchers also found that the process required about 30.7 gigajoules of energy to produce one tonne of carbon monoxide, placing it among the most competitive direct carbon capture and conversion methods reported so far.
The system also proved to be durable. It operated continuously for more than 100 hours while maintaining strong performance, suggesting it could be suitable for long-term industrial use.
To explore its potential for renewable energy, the team connected the technology to a high-efficiency solar cell. The combined system achieved a solar-to-fuel efficiency of about 5.5%, which is comparable to many similar technologies that rely on purified CO₂ instead of untreated industrial exhaust.
The researchers say their work demonstrates that useful chemicals can be produced directly from dirty factory emissions without costly gas-cleaning steps. If further developed, the technology could help industries reduce carbon emissions while creating valuable products from waste gases.
By simplifying carbon capture and making better use of renewable electricity, the new approach could support cleaner manufacturing and contribute to the transition toward more sustainable fuel and chemical production.
