Last time I wrote about carbon sequestration, I commented that I always viewed it as “one of those "10 years off" technologies”. Something that sounds cool, game-changing, but for some reason(s) it was too hard to pull off on a large scale, wasn’t economical, or needs more research and support.
Then again, never doubt human ingenuity, or dumb luck.
As with the sea urchin discovery, scientists stumbled upon another way to remove CO2 from the air and make it into a useful product, ethanol.
“We discovered somewhat by accident that this material worked,” said ORNL’s Adam Rondinone, lead author of the team’s study published in ChemistrySelect. “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.”
The team used a catalyst made of carbon, copper and nitrogen and applied voltage to trigger a complicated chemical reaction that essentially reverses the combustion process. With the help of the nanotechnology-based catalyst which contains multiple reaction sites, the solution of carbon dioxide dissolved in water turned into ethanol with a yield of 63 percent. Typically, this type of electrochemical reaction results in a mix of several different products in small amounts.
“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,” Rondinone said. “Ethanol was a surprise -- it’s extremely difficult to go straight from carbon dioxide to ethanol with a single catalyst.”
While this isn’t carbon sequestration the way the discovery with sea urchins was (locking up CO2 as chalk), this method would cycle the CO2 already in the air, rather than introduce more. It could help us from stop digging further into the climate hole.
Thanks to the nanotechnology, the reactions are very precise and result in few contaminants. Thanks to using readily available material (carbon, copper, nitrogen), costs are very low. Even better, it works at room temperature. This can lead to the application to be easily scaled up for industrial buildings or power plants.
Given the technique’s reliance on low-cost materials and an ability to operate at room temperature in water, the researchers believe the approach could be scaled up for industrially relevant applications. For instance, the process could be used to store excess electricity generated from variable power sources such as wind and solar.
“A process like this would allow you to consume extra electricity when it’s available to make and store as ethanol,” Rondinone said. “This could help to balance a grid supplied by intermittent renewable sources.”
Currently, cities with large solar panel deployment suffer from an overproduction of energy during daylight hours and a large loss of that capacity at night. Producing fuel from the excess capacity from solar generation would be a great way to “flatten the duck curve”, via directing the unused solar power to generate ethanol. Come night time, the power plant can switch to burning the carbon-neutral ethanol (since it was made from CO2 in the air) rather than burning natural gas.
Or, instead of using the ethanol in power plants, it can be easily used by our transportation sector. Most cars on the road today in the U.S. can run on blends of up to 10% ethanol, and ethanol represented 10% of the U.S. gasoline fuel supply derived from domestic sources in 2011. Most of the ethanol used to power our cars comes from converting food crops to ethanol. With this new method, no need to choose between food or fuel.
As with the sea urchin discovery, this one was also by happenstance. Imagine what we could actually do to resolve the climate crisis we’ve created if we actually put our minds to it.
