New process could capture 0.5 per cent of global CO2 emissions

The team at Strathclyde University published its research in Nature Sustainability, outlining how CO2 emissions can be captured during the normal crushing process of rocks commonly used in construction, by crushing them in CO2 gas. According to the team, almost no additional energy would be required to trap the CO2.

The materials and construction industry accounts for 11 per cent of global carbon emissions. More than 50 billion tonnes of rock is crushed worldwide every year and current crushing processes – standard in construction and mining – do not capture CO2.

Previous work has explored trapping carbon into single minerals by the same method, but the Strathclyde team’s research shows this is unstable and dissolves out of the mineral when placed in water. 

The paper documents how a larger proportion of carbon dioxide can be trapped in a stable, insoluble form in rocks composed of multiple different minerals by grinding it in CO2 gas. The resulting rock powders can then be stored and used in the environment for construction and other purposes.