The Humble Sea Urchin Could Hold Key To Tackling Climate Change

At the moment, pilot studies for Carbon Capture and Storage (CCS) systems propose the removal of CO2 by pumping it into holes deep underground, but it is both costly and has a long term risk of the gas leaking back out - possibly many miles away from the original downward source.

But now scientists have discovered that sea urchins use nickel ions to harness carbon dioxide from the sea to grow their exoskeleton - or shell. It could be a way to capture tonnes of CO2.

Using the nickel nanoparticles suspended in water vats at factories, power stations would capture the CO2 as it is pumped through, converting the gas into the chalk.

The nickel catalyst can be recycled and the by-product - the carbonate - is useful and not damaging to the environment.

Physicist Dr Lidija Siller, a PHD student at Newcastle University, discoverd the nickel enzyme 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.

"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, found in the shells of marine organisms, snails, pearls, and eggshells, 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 Siller adds: "The capture and removal of CO2 from our atmosphere is one of the most pressing dilemmas of our time.

"Our process would not work in every situation - it couldn't be fitted to the back of a car, for example - but it 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."

The team have patented the process and are now looking for an investor to take it forward.

This findings are published in the academic journal Catalysis Science & Technology.