Breakthrough Catalyst Makes CO2 Back Into a Hydrocarbon

Researchers at Ruhr-Universitaet-Bochum have discovered a catalyst that performs the highly selective conversion and recycling of the greenhouse gas carbon dioxide into ethylene. Ethylene, commonly found with natural gas, or distilled or cracked from crude oil, is an important source material for the chemical industry.

The team headed by Professor Dr. Beatriz Roldan Cuenya from Ruhr-Universität Bochum has published a new article describing how the plasma-treated copper can be used for this purpose in the journal Nature Communications. Full text available at this writing.

Traditional catalysts used for the electrochemical conversion of carbon dioxide into useful chemicals are not efficient enough. The reason is the materials do not have high selectivity; they produce a little ethylene and too many unwanted side products. The new catalyst changes that.

PhD student Hemma Mistry from the Institute for Experimental Physics IV in Bochum used copper films treated with oxygen or hydrogen plasmas as catalysts. Using these plasma treatments she altered the properties of the copper surface, rendering it rougher or less rough, for example, and oxidizing the material. Ms Mistry varied the plasma parameters systematically until she hit on the optimal surface properties.

Her best catalyst boasts a higher ethylene production rate than traditional copper catalysts. At the same time, it acts in a highly selective manner, which means that the amount of unwanted side products is considerable reduced. “It’s a new record for this material,” concluded Dr. Roldan Cuenya.

The researchers also identified the reason why this form of plasma treatment has been successful. Using synchrotron radiation, they analyzed the copper film’s chemical state during the catalysis of the reaction. Through these measurements, they detected the cause of the higher ethylene selectivity. The key component was positively charged copper ions at the catalyst surface.

It had been assumed that copper can only exist in its metallic form under reaction conditions. The researchers’ discovery has now disproved this assumption, and their findings were confirmed by additional microscopic analysis. “The results open up new possibilities for designing catalysts on the nanoscale with specific activity and selectivity,” said Dr. Roldan Cuenya.

For the purpose of the study, the group led by Dr. Roldan Cuenya collaborated with the group headed by Dr. Peter Strasser from Technische Universität Berlin, the group headed by Dr. Judith C. Yang from University of Pittsburgh, and the group headed by Dr Eric A. Stach from Brookhaven National Laboratory. The team also utilized the facilities at Stanford Synchrotron Radiation Lightsource.

The potential for CO2 catalyzed back to hydrocarbon is staggering. For now the Ruhr-Universitaet-Bochum result is a lab bench discovery. One quick way to put it to work if getting to scale allows, would be to catch the effluent from a coal fired electrical generating plant offering an abundance of CO2 now vented to the atmosphere.

Using the effluent for making hydrocarbons, sold and using the carbon again, would be a huge energy production proposal vastly cutting back on the CO2 per kilowatt hour. And if the hydrocarbon was used on site to generate even more power the CO2 could be used again. (And again).

The study isn’t saying the effective efficacy of the catalyst, an topic of extreme interest. But with the U.S. government killing the coal industry at a furious pace, this news just might be a wedge to slow down the destruction and save billions of dollars in capital plant, tens of thousands of jobs and save consumers a great deal of money.

Standing congratulations for the team are in order, with a sincere thanks. Thank You!