Finding uses for carbon dioxide means less climate change-inducing gases going to the atmosphere. And, in the case of CO2 captured to produce methanol, it also means creating transport fuel with environmental advantages over oil-derived gasoline. It's a one-two punch combination for the planet.
Chemists at the University of Southern California have discovered a stable catalyst that enables the conversion of CO2 to methanol in the presence of molecular hydrogen. Though methanol has been produced from CO2 before, they claim the new method is simpler and potentially cheaper, allowing more uses in the industrial world.
As explained here, the scientists use ruthenium to convert 79% of captured CO2 to liquid. Methanol, the simplest form of alcohol, is used extensively in industry as a foundation chemical. It can also be used in biodiesel and in fuel cells to generate electricity.
"CO2 can be captured from point sources such as coal-burning power plants, cement plants and ultimately the air—the final sink for all CO2," says Surya Prakash, a chemistry professor at the University of Southern California, in an email. "Commercial adoption depends on economic factors and the cost of hydrogen generated from non-fossil energy sources by electrolysis of water."
Along with two other USC researchers, George Olah and Alain Goeppert, Prakash has advocated for a "methanol economy." As a way of storing energy, methanol is more stable than hydrogen, they argue, and it's already widely in circulation, and adaptable for several uses. Prakash says replacing gasoline fuel with methanol could reduce CO2 pollution by 1 to 1.5 billion tons a year, or about 5% of global emissions.
Replacing everything doesn't seem likely. But, assuming the costs work out, converting CO2 to fuel doesn't sound like a bad idea at all.