Washington (IANS): An Indian-American physicist has devised a cleaner and more efficient way of capturing carbon dioxide from its polluting source, like coal-fired power plants.

Lawrence Livermore National Lab (LLNL) researcher Amitesh Maiti has come up with a screening method that would use ionic liquids -- molten salt that becomes liquid under the boiling point of water (100 degrees Celsius) -- to separate carbon dioxide from its source.

Using ionic liquids as a separation solvent has unique advantages over traditional solvents, said Mr. Maiti, who did his BSc in physics (honours) from the University of Calcutta in 1986 and his Ph.D, in condensed matter physics, at University of California, Berkeley, 1992.

There are major efforts to reduce carbon dioxide emissions from burning fossil fuel, as carbon dioxide is the principal greenhouse gas that is leading to global warming. But before it can be sequestered, the carbon dioxide must first be separated from its source, a step known as "capture". This new technique could significantly enhance the efficiency of the carbon dioxide capture process.

Currently, the few coal plants with commercial carbon dioxide capture capability all use processes based on chemical absorption with monoethanolamine (MEA), a general-purpose solvent developed by chemists some 75 years ago.

Unfortunately, it is non-selective, corrosive, requires the use of large equipment, and effective only under low to moderate partial pressures of carbon dioxide.

Mr. Maiti's new system overcomes many of these shortcomings. Over the past few years, several ionic liquids have been tested to be efficient solvents for carbon dioxide.

"By creating a computational tool that can decipher ahead of time which ionic liquids work best to separate carbon dioxide, it can be a much more efficient process when field tests are conducted."

Mr. Maiti's research featured as the cover story in a recent issue of ChemSusChem, a new journal focused on chemistry and sustainability.