Smoke emitting from chimney stacks
October 18, 2016

Researchers accidentally discover how to make ethanol using CO2

Scientists at the Oak Ridge National Laboratory (ORNL) have apparently accidentally found an efficient and inexpensive way to produce ethanol by using a copper nanoparticle catalyst to turn the greenhouse gas carbon dioxide into the renewable, alcohol-based fuel source.

According to New Atlas and Popular Science, the Tennessee-based research team found that by taking their copper nanoparticles catalysts and tiny spikes of carbon, and applying low levels (1.2 volts) of electricity, they could convert CO2 suspended into water into usable ethanol fuel.

Applying the voltage triggered a complex chemical reaction that effectively reversed the process of combustion at room temperature and with relatively little difficulty. Furthermore, their method resulted in the production of ethanol with an initial yield of 63%, the ORNL team reported.

“We discovered somewhat by accident that this material worked,” Adam Rondinone, lead author of a new paper detailing the process published in a recent edition of the journal Chemistry Select, explained in a statement. “We were trying to study the first step of a proposed reaction when we realized that the catalyst was doing the entire reaction on its own.”

“We’re taking carbon dioxide, a waste product of combustion, and we’re pushing that combustion reaction backwards with very high selectivity to a useful fuel,” he added. “Ethanol was a surprise – it’s extremely difficult to go straight from carbon dioxide to ethanol with a single catalyst.”

Technique could boost efforts to switch to renewable fuel sources

In actuality, Rondinone and his colleagues were attempting to convert carbon dioxide that had been dissolved in water into methanol, a chemical that is naturally produced by volcanoes and by various types of microbes, according to Popular Science. Much to their surprise, however, they wound up producing ethanol, which is useful as a renewable source of engine fuel.

One of the most important aspects of the process, the researchers explained, was the fact that it uses relatively common materials rather than exotic ones such as rare metals, focusing instead on arranging them into a specific nanoscale structures that limit unwanted side reactions. Since their technique used low-cost materials and can be completed at room temperature, the authors believe that it could be scaled up for use in various industrial applications.

For instance, the method could help store excess energy produced by wind or solar power units, capturing it when too much is generated and allowing it to be burned later when there is no wind or sunlight. “A process like this,” Rondinone said, “would allow you to consume extra electricity when it’s available... [and] help to balance a grid supplied by intermittent renewable sources.”

He and his ORNL colleagues Yang Song, Rui Peng, Dale Hensley, Peter Bonnesen, Liangbo Liang, Zili Wu, Harry Meyer III, Miaofang Chi, Cheng Ma and Bobby Sumpter are now on the lookout for ways to improve the ethanol production rate and to learn more about the behaviors and properties of their copper/carbon catalyst, according to New Atlas.

-----

Image credit: Thinkstock