Turning Carbon Dioxide into Liquid Fuel

by Joseph E. Harmon (Argonne National Laboratory) New electrocatalyst efficiently converts carbon dioxide into ethanol. ... A research team, led by the U.S. Department of Energy’s (DOE) Argonne National Laboratory in collaboration with Northern Illinois University, has discovered a new electrocatalyst that converts carbon dioxide (CO2) and water into ethanol with very high energy efficiency, high selectivity for the desired final product and low cost. Ethanol is a particularly desirable commodity because it is an ingredient in nearly all U.S. gasoline and is widely used as an intermediate product in the chemical, pharmaceutical and cosmetics industries.

“The process resulting from our catalyst would contribute to the circular carbon economy, which entails the reuse of carbon dioxide,” said Di-Jia Liu, senior chemist in Argonne’s Chemical Sciences and Engineering division and a UChicago CASE scientist in the Pritzker School of Molecular Engineering, University of Chicago. This process would do so by electrochemically converting the CO₂ emitted from industrial processes, such as fossil fuel power plants or alcohol fermentation plants, into valuable commodities at reasonable cost.

The team’s catalyst consists of atomically dispersed copper on a carbon-powder support. By an electrochemical reaction, this catalyst breaks down CO₂ and water molecules and selectively reassembles the broken molecules into ethanol under an external electric field. The electrocatalytic selectivity, or “Faradaic efficiency,” of the process is over 90 percent, much higher than any other reported process. What is more, the catalyst operates stably over extended operation at low voltage.

“We could couple the electrochemical process of CO₂-to-ethanol conversion using our catalyst to the electric grid and take advantage of the low-cost electricity available from renewable sources like solar and wind during off-peak hours.” Because the process runs at low temperature and pressure, it can start and stop rapidly in response to the intermittent supply of the renewable electricity. READ MORE

The upshot of this new research is the creation of a process that could reuse and recycle carbon dioxide for fuels and chemicals that today are derived from either oil or natural gas. Notice the role that low cost renewable energy plays in this scenario. What we are witnessing is a convergence of technologies that may result in ways to substantially lower the amount of carbon dioxide that gets added to the atmosphere by industry and at far lower cost than previously thought possible.

Ethanol and the other chemicals that could result from this and similar processes are essential building blocks for the plastics industry. If this discovery could be combined with the creation of new recyclable and biodegradable plastics, that would be a major step forward in constructing a circular economy, one that does not destroy the environment in the pursuit of profits.

The Drawdown Project has just published an update of its road map to a sustainable world, which it says can happen today without waiting for new technologies to appear. This latest news from Argonne National Lab could be incorporated with the ideas promoted by this latest Drawdown Review to help create a business environment built on the notion that the Earth’s resources are finite and should be used as wisely as possible. READ MORE

Excerpt from Popular Mechanics: There are questions here: Does the reaction require absolutely pure carbon dioxide, which is unusual to find in nature? This is an obstacle with most kinds of recycling, from a pizza box or the wrong kind of plastic all the way down to the microscopic level. What’s the hydrogen source? Hydrogen is also costly to separate and, as it stands today, primarily separated using fossil fuels. The catalyst is exciting, but that doesn’t erase existing concerns about how this kind of reaction works. READ MORE