A new development in carbon capture technology could provide an efficient and inexpensive way for natural gas power plants to remove carbon dioxide (CO2) from flue emissions, a necessary step to reduce greenhouse gas emissions.

Developed by researchers at the University of California, Berkeley, Lawrence Berkeley National Laboratory and ExxonMobil, the new technique uses a highly porous material called a metal-organic framework (MOF), modified with nitrogen-containing amine molecules to capture the CO2 and low temperature steam to flush out the CO2 for other uses or to sequester it underground.

Experiments carried out by the researchers showed a six times greater capacity from removing CO2 from flue gas than current anime-based technology, capturing more than 90% of the CO2 emitted. 

“For CO2 capture, steam stripping – where you can use direct contact with steam to take off the CO2 – has been a sort of holy grail for the field. It is rightly seen as the cheapest way to do it,” said Senior Researcher Jeffrey Long and UC Berkeley Professor. 

“These materials, at least from the experiments we have done so far, look very promising.”

Due to little market for most captured CO2, power plants would likely pump most of the CO2 back into the ground, or sequester it, where it would ideally turn into rock. The cost of scrubbing the emissions would have to be facilities by government policies.

The work was funded by ExxonMobil, which is working with both the Berkeley group and Long’s start-up, Mosaic Materials, to develop, scale up and test processes for stripping CO2 from emissions.

“We were able to take the initial discovery and, through research and testing, derive a material that in lab experiments has shown the potential to not only capture CO2 under the extreme conditions present in flue gas emissions from natural gas power plants, but to do so with no loss in selectivity,” said co-author Simon Weston, Project Lead at ExxonMobil Research and Engineering,.

“We have shown that these new materials can then be regenerated with low-grade steam for repeated use, providing a pathway for a viable solution for carbon capture at scale.”