On-site reactor could turn power plant emissions into valuable chemicals

On-site reactors at factories and power plants could turn carbon dioxide (CO2) into valuable chemicals on an "industrial scale", according to the developers of a new technology.

Developed at the University of Waterloo in Canada, the system could offer affordable conversion of emissions into fuels and other valuable chemicals.

The system yields 10-times more carbon monoxide (CO) – which can be used to make ethanol, methane and other useful substances – than existing, small-scale technologies now limited to testing in laboratories, Waterloo researchers said.

Individual cells can be stacked to form reactors of any size, the team said, making the technology a “customisable, economically viable solution that could be installed right on site”.

“This is a critical bridge to connect CO2 lab technology to industrial applications,” said chemical engineer Dr Zhongwei Chen. “Without it, it is very difficult for materials-based technologies to be used commercially, because they are just too expensive.”

The reactor includes electrolysers, which convert CO2 into CO using water and electricity. The electrolysers developed by the team have new types of electrodes and a liquid-based electrolyte, which is saturated with CO2 and flowed through the devices for conversion into CO via an electrochemical reaction. They take the form of 10x10cm cells, larger than previous devices, and can be stacked and configured in reactors of any size.

“This is a completely new model for a CO2 reactor,” said Dr Chen, the Canada research chair in advanced materials for clean energy. “It makes the whole process economically viable for industrialisation and can be customised to meet specific requirements.”

The researchers envision on-site reactors, perhaps the size of a house or more, at coal-fired power plants and factories. They would be directly fed CO2 emissions, eliminating the need to capture CO2 first.

The team is also developing plans to power the reactors with on-site renewable energy sources such as solar panels, contributing to the environmental benefits.

“I’m excited by the potential of this technology,” Dr Chen said. “If we really want to make a difference by reducing emissions, we have to concentrate on reducing costs to make it affordable.”

The work was outlined in Nature Energy.