Scientists find a way to suck up carbon pollution, turn it into baking soda and store it in the oceans
Grace Cook
September 14, 2024
"Scientists find a way to suck up carbon pollution, turn it into baking soda and store it in the oceans"
CNN article: https://www.cnn.com/2023/03/10/world/carbon-capture-sea-water-climate-intl-scn/index.html
science publication:
https://www.science.org/doi/10.1126/sciadv.adg1956#sec-3
When we burn fossil fuels for energy we create greenhouse gasses that accumulate in our atmosphere and trap heat, causing global warming. Perhaps the most notorious greenhouse gas is carbon dioxide. In order to combat the climate crisis we must severely reduce our use of fossil fuels and other carbon-emitting paraphernalia; however, equally important to reducing fossil fuel use is removing the greenhouse gasses that are built up in our atmosphere.
Since the industrial revolution we have built up immense amounts of carbon dioxide in our atmosphere. There are natural methods that remove carbon dioxide from the atmosphere, such as tree photosynthesis or the ocean carbon sink, but these natural processes cannot work fast enough or hold enough carbon dioxide within them to remove the mass emissions we have pumped into our air. Therefore, it is of paramount importance that we develop technologies to “suck” the carbon dioxide out of the air. Such technologies, referred to as carbon capture devices, have become an increasingly relevant area of research, and researchers at Lehigh University are working to optimize this revolutionary technology.
In her CNN article, Lauren Paddison explains how these researchers are innovating direct air capture technology to combat the climate crisis. The study she refers to, “direct air capture (DAC) and sequestration of CO2: Dramatic effect of coordinated Cu(II) onto a chelating weak base ion exchanger” by Chen et al, discloses further details about how incorporating copper into direct air capture devices can increase their efficiency and decrease costs. There are two main methods of extracting carbon dioxide from the atmosphere: the first involves installing carbon capture devices at the sources of emission, such as factory pipes, to soak up these high-concentration greenhouse gasses before they enter the atmosphere; the second method is called direct air capture, and constitutes removing carbon dioxide already released from the atmosphere. Direct air capture faces limitations because it is expensive and doesn’t actually capture much carbon dioxide; as Paddison explains, although carbon dioxide is a potent greenhouse gas, it still exists at relatively low concentrations in the air, making it difficult to suck much up from a random place in the atmosphere.
Chen et al is attempting to solve this limitation using copper. They propose using acid-base interactions with Cu(II) to create a sorbent (absorbent material) that enables carbon dioxide capture at two or three times the capacity of other currently available direct air capture sorbents. Chen et al found Cu(II) to be specifically successful for direct air capture because the metal coordinated with the N-donor atoms of the polyamine functional group in the weak base sorbent so it could act as an anion exchange site, giving it high capacity for carbon dioxide absorption. Once captured, the desorbed carbon dioxide is sequestered as baking soda which can be stored in ocean sinks. While this method works great for extracting carbon dioxide at low concentrations, Chen et al states that it is also cost-effective because the reagent materials are available from various manufacturers worldwide and it is easy and cheap to dissolve the baking soda product in seawater, eliminating a major barrier to carbon capture.
Overall, I think the Paddison article does a great job of summarizing Chen et al’s research and connecting it to the broader issue of climate change, all in terms that are easily digestible to the average reader. I respect Paddison’s choice to counter the use of our oceans as infinite carbon sinks, because it is a nuanced viewpoint that the average reader might not know or that people knowledgeable about the climate crisis might be curious about (I know I was). She exposes another nuance of carbon capture by describing the apprehension that some climate specialists have towards putting our resources towards carbon capture technologies because it signals to fossil fuel-reliant industries that it might be ok to keep emitting greenhouse gasses; “we can just take them out.”
While the CNN article did not go into great detail about the methods of Chen et al’s Cu(II)-coordinated direct air capture chemistry, or explain much of how exactly their copper sorbents were more groundbreaking than others, I don’t see any any problem with this lack of scientific detail because the average reader doesn’t have the know-how to understand it. I personally wish they had gone into a little more detail about, but perhaps that’s just me as a chemist– I doubt most readers clicking on a CNN article would understand chemistry jargon or care to know what methods the researchers used. In the absence of these chemical details, I appreciated Paddison expanding on the social implications of this direct air capture technology and connecting it to policy and the greater climate crisis; I think that the purpose of good research is to inform public decisions, so I find tying these complexities into the research is a success of the article. Overall, given Paddison’s succinct (while limited) research summary, lack of discrepancies or incorrect facts, and expansion into the nuances of direct air capture and the climate crisis, I rate her article a 9/10.
I definitely think that this article oversimplified the discussion of copper. The main part of the paper's discussion is around the copper complex and its versatility (large pH range, mechanism behind it). I also would give it a high score as well, since, like you have said in the post, the general audience doesn't care/doesn't understand how the ligand works and what it means to the research field. It is the focus, and I think the article has done a great job at it, to explain the social implications. All facts are correct, and no assumptions (good or bad) were made in the discussions. It does a good job crediting and linking the paper so that if anyone finds this interesting, it is easily accessible.
ReplyDeleteHi Richard, I do agree that the CNN article heavily simplified Chen et al's research findings that Cu(II) increases the capacity of their DAC technology. I think this ambiguity is excusable because after a quick background search I uncovered that the CNN author, Laura Paddison, is a specialist in climate journalism but does not have any background in chemistry or scientific research. Therefore it is reasonable to assume that even if she had wanted to give our readers a deeper dive into the chemistry of using copper in DAC, I doubt she has to know-how to explain it in clear or digestable words. She, like most popular media journalists, did not have the proper education to dissect Chen et al's research paper further. However, not all hope for detail lost because any curious chemist interested in doing a deeper dive could click on the link in the article to access the orginal research paper. In terms of what Paddison could explain about the Cu(II) research, she wrote in simple terms and without any misleading statements or assumptions (as you analyzed in your comment).
DeleteI agree with your rating on the CNN article and what previous comments have said. I appreciate how Paddison started by providing context as to why “direct air capture” and technology from the Chen et. al paper is important for the environment. The article describes the current challenges of this method and how the Chen et. al paper aid in addressing these challenges and uses quotes from one of the co-authors on the paper. One thing I also appreciate is how the CNN article offers multiple perspectives and talks about the issues surrounding disposing sodium bicarbonate into the ocean, not addressing high concentration emissions, and this work potentially distracting from reducing fossil fuel emissions. Although the CNN article oversimplifies the methods and the nuances of the experiment, it makes the science easier to follow and more accessible for a general audience.
ReplyDeleteHi Gigi, good analysis of the article! I also appreciate how the CNN article offers multiple perspectives about direct air capture and the potential issues associated with ocean dumping. However, as another commenter pointed out (and I then came to realize), I do think Paddison takes the multiple perspectives a little too far to the point of potentially confusing the reader about where the research findings came from. While I agree that including various perspectives in an article is good practice because it showcases more than one perspective and helps people develop more trust in the data, I also think that Paddison could have put more emphasis on Chen et al's study and made it clear that they were the researchers of focus.
DeleteI did not enjoy reading the CNN article because I felt that it did not focus on the research by Chen et al, but rather on the work of the Climeworks company in direct air capture. I was very confused as to whether Chen et al at Lehigh or Climeworks at ORCA had pioneered the technology discussed in the CNN article. ORCA was only mentioned briefly in the Science Advances publication as the world’s largest direct air capture plant. The researchers at ORCA were not collaborators on this publication. Climeworks performs similar research in Iceland to Chen et al, but my understanding was that the new Lewis acid-base sorbents with copper(ii) was not the work of Climeworks. I think this is extremely confusing to a reader. Was Paddison's goal to report on the ORCA plant or the research at Lehigh? I think she was trying to make a connection between the research, as both work towards the same goal of direct air capture, but one would have needed to read the article that she linked at the very beginning of her article on the ORCA plant.
ReplyDeleteEven though the summary of the research is valid, any mention of the research is spread throughout the article. It would have been a true four minute read instead of a ten minute one if she had talked about the research in the beginning, then left the context until later. Her paragraphs were connected in such a disjointed way. I would have given the article a much lower score.
Hi Genevieve, this is a very fair critique of the CNN article. I can actually agree with your idea that the CNN article puts too much emphasis on climeworks at ORCA and could give more clear-stated credit to Chen et al, because at the end of the day it is the findings of Chen et al that the article is discussing. I myself was a bit confused as to who the main researcher was the first time I read the article. After my second read it became clear that Chen et al were the main researchers and point of interest of the paper, but for the average person giving the article a single read-through it may not be as clear where the data came from.
DeleteI agree that the article did not go into detail regarding how the carbon is captured. Although the average, non scientific, reader would not necessarily the entire experimental process having some idea of how this CO2 captured is performed is beneficial. I think there is also an issue with this article in terms of mis representing the importance of CO2 removal; I think the article downplays the importance of cutting CO2 emissions and offers this removal method as the "path forward" rather than the "last resort". One final issue I had with this article is the lack of discussion around what dumping sodium bicarbonate into the oceans could do to the oceanic ecosystem. Although the affects are not super known, I think there probably is an expert out there that could offer a valuable prediction on what the effect of sodium bicarbonate is on oceanic ecosystems. For these reasons I would probably give the CNN article a much lower score.
ReplyDeleteHi Allison, good analysis. I agree that the CNN article left us wanting a little (or maybe a lot) more detail concerning Chen et al's methods and conclusions. On the topic of dumping the sodium bicarbonate product into the ocean, however, I think that Paddison gave a justifiable amount of detail. She touched on an issue that the original scientific article barely considered, which I find important, however I think it would have been unfitting to give more detail about the ecosystem impacts of ocean acidification considering this is an article about carbon capture technology, not about ocean acidification or marine ecosystems.
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