Scientists at the US Department of Energy's Pacific Northwest National Laboratory (PNNL) have created a system that efficiently captures CO2 before it can reach the atmosphere.

Crucially, it is also the least costly method devised to date, as per a PNNL press statement. The method also converts CO2 into methanol, which is widely used and can be sold after the process is complete. 

Several measures aimed at mitigating the worst effects of climate change

The Intergovernmental Panel on Climate Change (IPCC) offered a dire warning to the world with its climate change report last year. The report outlined several measures aimed at mitigating the worst effects of climate change. The report highlighted the fact that simply reducing emissions was no longer enough; we will also have to remove CO2 from the atmosphere using carbon capture and storage technologies.

Though carbon capture may be a crucial component in the fight against climate change, scientists are working hard to develop methods that are viable from a business perspective. Up to now, the high cost of carbon capture technology has been a barrier to its widespread development on a global scale.

The PNNL scientists believe their new method provides a strong financial incentive in the form of menthol. The chemical is widely used as a fuel and is a key ingredient in plastics, paint, and construction materials. 

 

PNNL chemist David Heldebrant, who led the team behind the new method, compared the new system to recycling. "That's essentially what we're trying to do here. Instead of extracting oil from the ground to make these chemicals, we're trying to do it from CO2 captured from the atmosphere or from coal plants, so it can be reconstituted into useful things.

"You're keeping carbon alive, so to speak, so it's not just 'pull it out of the ground, use it once, and throw it away.' We're trying to recycle the CO2, much like we try to recycle other things like glass, aluminium, and plastics." 

A new world of 'CO2 conversion chemistry'

Heldebrant and his team, who published a paper detailing their method in the journal Advanced Energy Materials, designed their system to fit inside coal, gas, and biomass-fired power plants, as well as cement kilns and steel plants.

In their tests, they used a capture solvent developed at PNNL to catch CO2 molecules before they're emitted. The solvent then converts them into methanol and other substances.

Though Heldebrant and his team do concede that the new method still requires a long research and development phase before going to market, the method could also help to store CO2 in materials that are not burnt back into the atmosphere.

As such, as Casie Davidson, manager for PNNL's carbon management and fossil energy market sector, said: "The team's integrated approach opens up a world of new CO2 conversion chemistry. There's a sense that we're standing on the threshold of an entirely new field of scalable, cost-effective carbon tech. It's a very exciting time."

One method developed by RMIT University researchers in Australia quickly converts CO2 into solid carbon, while another developed by UCLA researchers mimics the seashell-forming process. While these methods may be effective, they arguably don't provide as strong a financial incentive as the new PNNL method. And that could be key to turning the tide on climate change.