Sea Creatures Inspire CO2 Sponge

The porous structure of sea cucumbers could be the perfect model to create a sponge that absorbs C02 and boosts hydrogen fuel production, said an Australian researcher.

Chemical engineer Andrew Harris of the University of Sydney said hydrogen is the only truly clean fuel we know of. "The only by-product of hydrogen is pure water and you can drink it."

According to Harris, Australia's main source of hydrogen currently comes from burning fossil fuels, which also releases C02. He said the C02 released during this process could be absorbed by sponges made of calcium oxide.

Harris is using a group of marine creatures known as echinoderms, which includes starfish, sea urchins and sea cucumbers, as his source of inspiration.

He said the creatures have an "awesome" calcium carbonate skeleton, ideal for absorbing C02, which he hopes to mimic the structure to produce a synthetic sponge.Harris said removing carbon dioxide from the combustion process dramatically increases the output of hydrogen from 50 percent to 80 percent of the total volume.

To carry out their research Harris and his team have been awarded a research grant from European Energy Company E.ON.

They will investigate materials like silicon carbide and alumina to build synthetic sponges, which would be grafted with calcium oxide to absorb the C02.

To keep them cost effective the C02 would have to be re-released so the sponges can be used again.

"You want to be able to use the calcium oxide again and again. It's prohibitively expensive to mine calcium oxide just to mop up C02," said Harris.

At present he has several PhD students working on innovative ways to use the re-released C02.

Harris hopes in the future, hydrogen will be sourced from biomass waste rather than fossil fuels.

"We did an experiment a couple of years back and found that if all the forest waste, left over crops and wood waste sent to landfill in Australia was converted into hydrogen there would be enough energy to run every bus in every city for a year on the waste," he said.