Scientists make carbon capture breakthrough

Carbon capture has been touted as a solution to reduce global carbon dioxide emissions Keystone

Swiss scientists have contributed to making carbon capture more practical and less energy intensive by combining a powder-like solid material with a liquid mixture to create a “slurry”. This offers the potential for scaling up carbon capture and storage solutions.

Carbon capture has been touted as a solution to reduce global carbon dioxide (CO2) emissions by collecting the CO2 released from factories and power plants and storing it. However, there are many obstacles that prevent it from being scaled up to the extent necessary to be a really effective solution.

The most common approach to carbon capture uses liquid amine solutions, which can absorb CO2 from the atmosphere. However, it is very energy consuming to release the CO2 from the liquid as it requires a lot of heat.

The solid materials, known as metal-organic frameworks (MOFs), are made up of metal atoms with nano-size pores that collect CO2. They are very energy efficient but are not very practical because of the nature of the substance.

 “Try to transport baby powder. You cannot pump it as it goes everywhere,” Berend Smit, one of the co-authors of the paper and director of the Energy CenterExternal link at the Swiss Federal Institute of Technology Lausanne (EPFL), told swissinfo.ch.

Slurry

To overcome this problem, the researchers have come up with the best of both worlds by creating a slurry that consists of a solid part called ZIF-8, which is suspended in a liquid mixture of 2-methylimidazole glycol.

Because it combines the low cost and efficiency of nano-porous materials with the ease of a liquid-based separation process, the slurry successfully addresses these two main obstacles to the implementation of carbon capture in the real world.

This was not attempted before because if a solid absorbent is used in conjunction with a solvent, the liquid would fill up the pores meant for CO2.

“With these new materials like ZIFs we can now have crystalline materials where the pores are sufficiently large for CO2 to enter but too small for the solvent to enter,” Smit explained.

The breakthrough method was a result of a collaboration between scientists from EPFL, China University of Petroleum, University of California, Berkeley and Beijing University of Chemical Technology and is published in the scientific journal Nature CommunicationsExternal link.