It can turn CO2 into chalk!
A team of boffins looking at ways of capturing global warming gas have cried ‘Eureka!’ over the humble sea urchin. Experts at Newcastle University,have discovered that in the presence of a nickel catalyst, CO2 can be converted rapidly and cheaply into the harmless, mineral, chalk.
This discovery, published in the latest issue of Catalysis Science & Technology, has the potential to revolutionize the way carbon is captured enabling the reduction of CO2 emissions — the key greenhouse gas which many believe is responsible for climate change.
Dr Lidija Šiller, a physicist and Reader in Nanoscale Technology at Newcastle University, says the discovery was made completely by chance.
‘We had set out to understand in detail the carbonic acid reaction — which is what happens when CO2 reacts with water — and needed a catalyst to speed up the process,’ she said.
‘At the same time, I was looking at how organisms absorb CO2 into their skeletons and in particular the sea urchin which converts the CO2 to calcium carbonate.
‘When we analysed the surface of the urchin larvae we found a high concentration of nickel on their exoskeleton. Taking nickel nanoparticles which have a large surface area, we added them to our carbonic acid test and the result was the complete removal of CO2.’
Each year, humans emit on average 33.4 billion metric tons of CO2 — around 45% of which remains in the atmosphere. Typically, a petrol-driven car will produce a ton of CO2 every 4,000 miles.
Chalk, makes up around 4% of the Earth’s crust and acts as a carbon reservoir, estimated to be equivalent to 1.5 million billion metric tons of carbon dioxide. It is the main component of shells of marine organisms, snails, pearls, and eggshells and is a completely stable mineral, widely used in the building industry to make cement and other materials and also in hospitals to make plaster casts.
The process developed by the Newcastle team involves passing the waste gas directly from the chimney top, through a water column rich in nickel nano-particles and recovering the solid calcium carbonate from the bottom.
Dr Šiller adds: ‘The capture and removal of CO2 from our atmosphere is one of the most pressing dilemmas of our time.Our process is an effective, cheap solution that could be available world-wide to some of our most polluting industries and have a significant impact on the reduction of atmospheric CO2.’
Pic: National Geographic