Scientists working on new idea to capture CO2 from air

A new way of sucking carbon dioxide from the air and storing it in the sea has been outlined by scientists. They say that this novel approach captures CO2 from the atmosphere up to three times more efficiently than current methods.

The warming gas can be transformed into bicarbonate of soda and stored safely and cheaply in seawater. The new method could speed up the deployment of carbon removal technology, experts say.

While the world has struggled to limit and reduce emissions of carbon dioxide in recent decades, several companies have instead focussed on developing technology to remove CO2 from the atmosphere.

Climeworks in Switzerland is perhaps the best known. Over the past ten years it has developed machines to suck in the air from the atmosphere that filter and trap the carbon dioxide molecules.

Climeworks have established the world’s largest direct air capture plant in Iceland. At a plant in Iceland the captured CO2 is injected deep underground where it is permanently turned into stone.

The company has recently started selling a certified carbon removal service to large corporate clients including Microsoft, Spotify and Stripe.

However, one big problem for most current approaches to direct air capture is cost.

CO2, although a powerful warming agent, is relatively diluted in the atmosphere at around 400 parts per million (ppm) in air.

So big machines that require large amounts of energy are needed to both absorb and discharge the CO2.

This new approach, using off-the-shelf resins and other chemicals, promises far greater efficiency and lower cost, say the scientists involved.

The research team have borrowed an approach used for applications in water, and “tweaked” existing materials to remove CO2 from the air.

In tests, the new hybrid absorbing material was able to take in three times as much CO2 as existing substances.

The development, while in its early stages, has been welcomed by others in the field.

One of the big challenges in capturing CO2 is what to do with the trapped gas.

Storing it under the ground or sea in former oil wells is one widely used approach. But the new paper suggests that with the addition of some chemicals the captured CO2 can be transformed into bicarbonate of soda and stored simply and safely in sea water.

Despite the rapid deployment of renewable energy, controlling rising temperatures will likely require extensive carbon removal as well.

Some scientists are reluctant to put too much emphasis on new and emerging technologies like direct air capture because they fear that it could dilute the carbon cutting efforts of governments and individuals.

But with the temperature thresholds of the Paris climate agreement under threat from rising emissions, many others feel that the rapid deployment of direct air capture in addition to massive cuts in carbon is the best hope of avoiding dangerous climate change.

Tags: Carbon Capture, Climeworks, CO2, Scientists