CO2 capture drives metal purification

Abstract

Capturing the carbon dioxide emitted by fossil fuel power stations or industrial plants offers a vital way to reduce global greenhouse gas emissions. But carbon capture technologies are still considered too costly for widespread deployment. Now chemists at the University of Lyon have developed a method to capture CO2 while simultaneously purifying mixtures of metals. By coupling these two processes together, they argue, CO2 capture can generate value in the form of purified metals, potentially making carbon capture more economically viable (Nat. Chem. 2019, DOI: 10.1038/s41557-019-0388-5). Current carbon capture systems often use amines that react with CO2 in flue gas to form carbamates. These compounds can be separated and heated to release a stream of pure CO2, regenerating the amine so that it can be cooled and reused. But the huge temperature swings involved make this a costly approach. Meanwhile, the CO2 released from the amines is sometimes used to