Decarbonizing industries like steel and cement is a difficult challenge. Both involve emitting large amounts of carbon dioxide both from burning fossil fuels and from intrinsic chemical reactions taking place. A potential solution is to capture the carbon dioxide emissions and either use them or store them away. But this sort of carbon capture is not easy and can be quite expensive.
The most common method for capturing carbon dioxide emissions from industrial plants uses chemicals called liquid amines which absorb the gas. But the chemical reaction by which this occurs only works well at temperatures between 100 and 140 degrees Fahrenheit. Cement manufacturing and steelmaking plants produce exhaust that exceeds 400 degrees and other industrial processes produce exhaust as hot as 930 degrees.
Costly infrastructure is necessary to cool down these exhaust streams so that amine-based carbon capture technology can work.
Chemists at the University of California, Berkeley, have developed a porous material – a type of metal-organic framework – that can act like a sponge to capture CO2 at temperatures close to those of many industrial exhaust streams. The molecular metal hydride structures have demonstrated rapid, reversible, high-capacity capture of carbon dioxide that can be accomplished at high temperatures.
Removing carbon dioxide from industrial and power plant emissions is a key strategy for reducing greenhouse gases that are warming the Earth and altering the global climate. The captured CO2 can be used to produce value-added chemicals or can be stored underground or chemically-reacted into stable substances.
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Breakthrough in capturing ‘hot’ CO2 from industrial exhaust
Photo, posted March 3, 2010, courtesy of Eli Duke via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio