In addition to increasing overall-performance of carbon capture technology, the new method could also enable commercial production of more sustainable fuel cells.
Capture 99% of carbon dioxide from air
The new system, described in a new article in the journal Nature Energy, actually born-out of a setback in another research project. The team behind the new technology was originally worked on the hydroxide exchange membrane (HEM) fuel cell, an affordable & environmentally-friendly alternative to traditional acid based fuel-cells.
While working on this technology, the team had to face a serious obstacle. HEM fuel cells, they discovered, are very sensitive to carbon-dioxide in the air, which makes it difficult for the batteries to function properly.
A few years later, researchers who tried to combat the effects of carbon-dioxide on HEM fuel cells use it to our advantage.
“Once we dug into the mechanism, we realized that the fuel cells captured almost every bit of carbon-dioxide that came in-to them, and they were really good at separating it to other-side,” said Brian Setzler, co-author of paper.
The team took advantage of the built-in “self-purge” process seen in HEM fuel cells to create a carbon-dioxide separator that could be placed upstream from fuel cells-stacks. “Our approach turns out to be very efficient. We can capture 99% of the carbon dioxide from the air in a single pass if we have the right design & right configuration,” said UD Professor Yushan Yan, head of study.
Carbon capture: silver bullet or dangerous distraction?
Today, the device has a more compact system that can filter larger volumes of air. According to the researchers, their first prototype, the size of a soda can, is capable of filtering about 10 liters of air per minute and removing about 98% of the CO2.
Additionally, they discovered that a smaller electrochemical cell measuring 2 inches by 2 inches could be used to continuously remove about 99% of the CO2 present in the air at a rate of about two liters per minute.
The team’s prototype was designed to remove CO2 from vehicle exhaust, although it could also be used for other applications, including aircraft, spacecraft & submarines.
Although the new system has great potential to improve carbon capture as a whole, some scientists have warned that carbon capture will not be enough to avoid the climate crisis. Indeed, in July of last year, scientists at the U.S Center for International Environmental Law went so far as to write that carbon capture was “dangerous distraction” that could be used as an excuse to slow the transition from fossil fuel consumption. However, several major carbon capture projects are currently underway, including a new carbon capture facility in Scotland which will remove-up to 1 million tonnes of CO2 from the atmosphere per year.