“You get the same fuel, although in principle it could be much more efficient because you are not relying on biomass,” says Matthew Kanan, an associate professor of chemistry at Stanford who co-authored the paper. Critics say that growing crops for biofuels is energy-intensive and takes up vast tracts of nonagricultural land, using too much water and fertilizer. The Stanford group starts with copper metal and, by heating it in air, grows a layer of copper oxide on top. For the Nature study, Kanan and Li built an electrochemical cell – a device consisting of two electrodes placed in water saturated with carbon monoxide gas. The selectivity for oxygenates, with ethanol as the major product, demonstrates the feasibility of a two-step conversion of CO 2 to liquid fuel that could be powered by renewable electricity. They say the process, described in a paper published in Nature on Wednesday, could be powered by renewable sources of electricity, such as solar and wind, and would be an alternative to traditional biofuel production. Kanan envisions taking carbon dioxide (CO2) from the atmosphere to produce carbon monoxide, which, in turn, would be fed to a copper catalyst to make liquid fuel.
– Could ethanol someday essentially be produced out of thin air? A group of scientists has published research in Nature detailing a new method of making ethanol out of carbon monoxide gas, instead of corn or sugarcane, Reuters reports. Researchers saturated water with the gas, then zapped it with a novel device featuring two electrodes, one made of what they're calling "oxide-derived copper," to convert it into fuel. "I emphasize that these are just laboratory experiments today," lead researcher Matthew Kanan says. He expects to have a prototype device ready in two to three years. The environmental implications are profound. Critics of ethanol say it drives up food prices and consumes loads of land and water. It can take more than 800 gallons of water to grow enough corn to make 3 gallons of ethanol, Phys.org points out. What's more, researchers envision a two-step process in which the carbon monoxide is derived from carbon dioxide in the air, providing an "economic incentive" for scrubbing carbon from the atmosphere, the MIT Technology Review reports. The new process could also work on a far smaller scale than biomass methods; the Review envisions rooftop solar panels generating fuel that's kept in water heater-sized tanks. (More on the toll ethanol takes on the environment here.)