Scientists in Singapore say they have found a way to turn planet-warming carbon dioxide into clean-burning methanol using a process that uses less energy than previous attempts.

The scientists at the state-backed Institute of Bioengineering and Nanotechnology said on Thursday they used non-toxic organocatalysts to make ethanol, a biofuel that is also used as an industrial feedstock.

In a statement, the institute said the team, led by Yugen Zhang, used N-heterocyclic carbenes (NHCs), an organocatalyst in the chemical reaction with carbon dioxide.

NHCs are stable and the reaction between NHCs and carbon dioxide can take place under mild conditions in dry air, the statement said, adding only a small amount of the catalyst was needed.

The process also used hydrosilane, a combination of silica and hydrogen.

Hydrosilane provides hydrogen, which bonds with carbon dioxide in a reduction reaction. This carbon dioxide reduction is efficiently catalyzed by NHCs even at room temperature, Zhang said in the statement.

Methanol can be easily obtained from the product of the carbon dioxide reaction, Zhang added.

Previous attempts to turn CO2 into more useful products have required more energy input and a much longer reaction time, the team said.

But they didn't say how the process could be scaled up to fight climate change by capturing and transforming some of the billions of tons of CO2 produced annually by burning fossil fuels.

(Reporting by David Fogarty; Editing by David Fox)