Sieves could put a lid on greenhouse gas

Brisbane and German scientists have teamed up in a $4.2 million project to build and test microscopic sieves that could potentially trap environmentally destructive greenhouse gases before they escape coal-fired power stations and refineries.

The gas separation technology can be fitted to existing power stations and petrochemical plants to produce hydrogen, a clean energy carrier, and capture carbon dioxide, a greenhouse gas that worsens global warming.

The scientists working on the technology are from the Australian Research Council's (ARC) Centre for Functional Nanomaterials at The University of Queensland and a German industrial research institute, Forschungszentrum Jülich (FZJ).

Professor Max Lu, the Director of the ARC Centre for Functional Nanomaterials, said the technology involved pumping synthesis gas from coal through a metal-supported molecular sieve in a pressurised chamber.

Lu said the nano sieve was coated with thin film of zirconium and titanium oxides which separated hydrogen from the greenhouse gases such as carbon dioxide.

"The film we coat it in behaves like the sieve which has tiny nano-holes, one billionth of a metre, that allow the smaller hydrogen molecules to go through," Lu said.

"It will turn dirty coal use clean and leave hydrogen that can be used in many other sectors such as transportation using fuel cells."

Water would be the only by-product for coal power stations using the sieves as the carbon dioxide could be buried and hydrogen converted into electricity in fuel cells.

The research is supported by UQ, the Centre for Low Emission Technology which is backed by Queensland power and mining companies and FZJ, the German state of North Rhine Westphalia and German industrial partners.

Project manager Dr Joe da Costa said UQ's molecular sieve technology was cheaper and had superior engineering performance compared to conventional gas separation technologies and that it was important environmental technology especially given more than 80% of Australia's power came from coal-powered plants.

"Many countries have good coal resources that can last at least for another 150 years but to use that more cleanly and efficiently you have to think about new technologies," da Costa said.

"Coal is very cheap and the technology will allow our society to meet our obligation to reduce the amount of carbon dioxide that's pumped into the atmosphere."

For further information visit University of Queensland