Carbon Dioxide and the New Stone Age

Turning pollution into stone.

By Steve VolkDec 15, 2016 6:00 AM
Icelandic geothermal plant
An Icelandic geothermal plant separates the CO2 from steam and locks it below the surface. (Credit: AP Photo/Brennan Linsley)

Newsletter

Sign up for our email newsletter for the latest science news
 

In June, researchers working in Iceland announced they had turned carbon dioxide into stone. The team captured carbon dioxide emitted by a geothermal plant and injected it, along with water, into basalt rock. The gas mineralized into calcium carbonate, the main component of limestone.

This transformation from gas to solid avoids the pitfalls of other sequestration projects, where carbon dioxide can leak into the atmosphere or groundwater. The project, called CarbFix, won’t act as a global warming panacea because it uses more water than some industrial sites can offer. But its success is noteworthy amid some problematic efforts to pull carbon dioxide from the atmosphere.

An injection site core shows CO2-bearing rock captured under-ground. (Credit: Carbfix/Sandra Snaebjornsdottir)

Going one step further, another team was expected to announce in late 2016 that it had found a way to mineralize carbon dioxide — without adding any water. Todd Schaef, a geochemist at the Pacific Northwest National Laboratory, says the team’s solution brings the gas to a “supercritical state,” increasing the temperature and pressure before injecting it into basalt rock. Once supercritical, carbon dioxide has properties of both gas and liquid, allowing it to undergo a chemical reaction with the basalt, turning CO2 into stone.

“In an operation that produces a lot of wastewater,” Schaef says, “the CarbFix method will make perfect sense. But where you don’t have that wastewater, perhaps you’d want to go with our approach.”

1 free article left
Want More? Get unlimited access for as low as $1.99/month

Already a subscriber?

Register or Log In

1 free articleSubscribe
Discover Magazine Logo
Want more?

Keep reading for as low as $1.99!

Subscribe

Already a subscriber?

Register or Log In

More From Discover
Recommendations From Our Store
Shop Now
Stay Curious
Join
Our List

Sign up for our weekly science updates.

 
Subscribe
To The Magazine

Save up to 40% off the cover price when you subscribe to Discover magazine.

Copyright © 2023 Kalmbach Media Co.