08 Nov 2012:
Molecular ‘Trap Door’ Method
May Reduce Costs of Carbon Capture
Australian scientists have developed a method for trapping carbon dioxide
that they say could ultimately reduce the costs of separating and storing carbon from fossil fuel emissions. Writing in the Journal of the American Chemical Society
, researchers from the University of Melbourne say they have produced
an ultra-fine sieve that separates only carbon dioxide from a gas stream, acting as a sort of “molecular trapdoor.” According to the study, the new method — which can be used in power plants or during natural gas extraction — uses a chemical called a chabazite that allows carbon dioxide to pass through but blocks other chemicals. While many such existing carbon capture technologies use similar “sieves,” they often require additional stages of refining and extraction before yielding a pure form of CO2. “Because [the new process] allows only carbon dioxide molecules to be captured, it will reduce the cost and energy required for separating carbon dioxide,” said Paul Webley, a professor at the University of Melbourne and one of the study’s authors. One potential early application for the technology may be in natural gas drilling
, where there are often large concentrations of carbon dioxide that must be extracted before the gas can be compressed and liquefied.