Environment

Bubble-like "Memzyme" increases speed and efficiency of carbon capture

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Scientists have developed a thin, bubble-like membrane which could help filter CO2 out of flue gas
Scientists have developed a thin, bubble-like membrane which could help filter CO2 out of flue gas
Sandia National Laboratories researcher Susan Rempe peers through bubbles
Randy Montoya

Alongside green energy production, capturing carbon emissions at the source is another avenue in the fight against climate change. New materials and treatments are regularly improving carbon capture efficiency, and now scientists have developed an efficient low-cost technique that makes use of an ultra-thin membrane, like a bubble, to filter CO2 out of flue gas.

The researchers, from Sandia National Laboratories and the University of New Mexico, call their creation a CO2 Memzyme – a membrane full of enzymes. With a liquid layer 10 times thinner than a soap bubble, CO2 diffuses through this membrane and is captured and dissolved, while allowing nitrogen and oxygen to pass through. Bubbles are notoriously fragile, though, so to prevent breaks or leakage, the team bolstered theirs with a silica-based support of nanopores, made up of a relatively thick layer that repels water, and a thin layer that attracts it.

Enzymes were added to the liquid layer to help speed up the C02 dissolution process. The team used carbonic anhydrase, an enzyme found in human muscles, blood and lungs that helps the body process and remove carbon dioxide, and found that it increased the rate that the CO2 dissolved by a factor of 10 million. With the nanopores forming an unusual environment for the enzymes, the researchers ran molecular simulations to figure out how the carbonic anhydrase was behaving in the cramped conditions and see how they might improve its performance.

The simulations showed that although the nanopores aren't much bigger than the enzymes themselves, several of them could cram into the space and work together to help process the CO2. The nanopore structure helped protect the enzymes as well, meaning they could stay dissolved and active in much higher concentrations than usual, and do so for months on end, at temperatures as high as 140° F (60° C).

Altogether, the team claims their design is 10 to 100 times more selective for CO2 over nitrogen in passing flue gas than existing carbon capture membranes, and it performs 100 times faster. At the other end, the CO2 that's produced is 99 percent pure, which can be used in a variety of ways, like manufacturing concrete or producing biofuel from bacteria and algae.

While the team is currently seeking out partners to help scale the technology up for use in power plants, lab tests have shown promise.

"If we applied it to a single coal-fired power plant, then over one year we could avoid CO2 emissions equivalent to planting 63 million trees and letting them grow for 10 years," says Rempe.

The team received a patent for the Memzyme technology earlier this year and, although it's still early days, say it could be the first to meet the Department of Energy's national clean energy goal of having technology that can capture 90 percent of carbon emissions at a cost of US$40 per ton by 2025.

The Memzyme is described in the video below.

Source: Sandia Laboratory

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7 comments
Ken Brody
Looks like a possible technology for a SCUBA rebreather.
msw48
Well, since we seem to have too much CO2 and too little graphene, maybe this a first step in my brain-fart visualization of attaching graphene generators to CO2 emission sources. Maybe someday the CO2 could be a more valuable intermediate product than the process creating it?
HalSlater
Why are you pimping for the coal industry? Demand for coal is FALLING not "going up" and CO2 is just one of the many toxic pollutants it creates and solar electricity is cheaper than coal, even after less than two decades of development (compared to the 100's of years head start coal has had.) Facts are important, please stick to them.
Kpar
"capturing carbon emissions at the source is another avenue in the fight against climate change"
Nonsense.
christopher
" Capturing carbon emissions at the source is an important weapon in the fight against climate change​. "
Um, no it is not.
Climate change is not within the power of the human race to make any kind of noticeable difference to whatsoever. This will never make any difference, even if everyone in the planet banded together to try, which they will not.
We eat, we live and cook and heat and move around, and we reproduce. All 7.5+ billion of us. Yes - billion. The *vast* majority do not care, and never will, and even if they did, are powerless to make any difference. Everyone who does care is totally deluded over just how ridiculously insignificant they are, and the overwhelming insignificance of everything they could possibly ever achieve when it comes to this topic.
The arrogance of the fools who totally fail to grasp this is frightening - most of them claim to be scientists, but they have utterly no comprehension of the scale of this topic and the vastness of the numbers involved.
So long as us taxpayers are fool enough to worship this bogosity, governments will send our tax money to more of these research charlatans so they can produce cool stories and tales of woe for us, all the while making no *noticeable* difference.
ljaques
Like Christopher, I was ready to dump on this, but I feel that anything we can do to mitigate our human footprint is a good thing. I agree with everything Christopher said, except that they are making a noticeable difference. Everything nowadays costs more as a result of the money going to Crimate Change. Worthy charities are struggling more, taxpayers find extra trillons hung onto the National Debt, and people are starving as a result of the increase in the cost of corn because it is so subsidized now that Big Agra is sending all its corn to the ethanol producers instead of the food makers. Yes, these Bleevers in Crimate Change are making a noticeable difference. Maybe this tech can help limit man's output, and maybe it can be nudged into doing other magic. I applaud their work, not their idiotic AGWK ideals.
Fretting Freddy the Ferret pressing the Fret
Big Oil continues their funding of disinformation about climate change in the US. The sad state of affairs is more than evident if you look at some of these comments. Fortunately, the rest of the developed world is spared from this ruthless campaign against climate science.
Regardless, the world moves on as we fight the emissions of numerous types of pollution that harm our well-being and the ecosystem.