Is Carbon Dioxide the New Black? Yes, If These Fabric-Designing Scientists Have Their Way
Each year the world releases around 33 billion tons of carbon dioxide into the atmosphere. What if we could use this waste carbon dioxide to make shirts, dresses and hats? It sounds unbelievable. But two innovators are trying to tackle climate change in this truly unique way.
Chemist Tawfiq Nasr Allah set up Fairbrics with material scientist Benoît Illy in 2019. They're using waste carbon dioxide from industrial fumes as a raw material to create polyester, identical to the everyday polyester we use now. They want to take a new and very different approach to make the fashion industry more sustainable.
The Dark Side of Fast Fashion
The fashion industry is responsible for around 4% of global emissions. In a 2015 report, the MIT Materials Systems Laboratory predicted that the global impact of polyester fabric will grow from around 880 billion kg of CO2 in 2015 to 1.5 trillion kg of CO2 by 2030.
Professor Greg Peters, an expert in environmental science and sustainability, highlights the wide-ranging difficulties caused by the production of polyester. "Because it is made from petrochemical crude oil there is no real limit on how much polyester can be produced...You have to consider the ecological damage (oil spills, fracking etc.) caused by the oil and gas industry."
Many big-name brands have pledged to become carbon neutral by 2050. But nothing has really changed in the way polyester is produced.
Some companies are recycling plastic bottles into polyester. The plastic is melted into ultra-fine strands and then spun to create polyester. However, only a limited number of bottles are available. New materials must be added because of the amount of plastic degradation that takes place. Ultimately, recycling accounts for only a small percentage of the total amount of polyester produced.
Nasr Allah and Illy hope they can offer the solution the fashion industry is looking for. They are not just reducing the carbon emissions that are conventionally produced by making polyester. Their process actually goes much further. It's carbon negative and works by using up emissions from other industries.
"In a sense we imitate what nature does so well: plants capture CO2 and turn it into natural fibers using sunlight, we capture CO2 and turn it into synthetic fibers using electricity."
Experts in the field see a lot of promise. Dr Phil de Luna is an expert in carbon valorization -- the process of converting carbon dioxide into high-value chemicals. He leads a $57-million research program developing the technology to decarbonize Canada.
"I think the approach is great," he says. "Being able to take CO2 and then convert it into polymers or polyester is an excellent way to think about utilizing waste emissions and replacing fossil fuel-based materials. That is overall a net negative as compared to making polyester from fossil fuels."
From Harmful Waste to Useful Raw Material
It all started with Nasr Allah's academic research, primarily at the French Alternative Energies and Atomic Energy Commission (CEA). He spent almost 5 years investigating CO2 valorization. In essence, this involves breaking the bonds between the carbon and oxygen atoms in CO2 to create bonds with other elements.
Recycling carbon dioxide in this way requires extremely high temperatures and pressures. Catalysts are needed to break the strong bonds between the atoms. However, these are toxic, volatile and quickly lose their effectiveness over time. So, directly converting carbon dioxide into the raw material for making polyester fibers is very difficult.
Nasr Allah developed a process involving multiple simpler stages. His innovative approach involves converting carbon dioxide to intermediate chemicals. These chemicals can then be transformed into the raw material which is used in the production of polyester. After many experiments, Nasr Allah developed new processes and new catalysts that worked more effectively.
"We use a catalyst to transform CO2 into the chemicals that are used for polyester manufacturing," Illy says. "In a sense we imitate what nature does so well: plants capture CO2 and turn it into natural fibers using sunlight, we capture CO2 and turn it into synthetic fibers using electricity."
The Challenges Ahead
Nasr Allah met material scientist Illy through Entrepreneur First, a programme which pairs individuals looking to form technical start-ups. Together they set up Fairbrics and worked on converting Nasr Allah's lab findings into commercial applications and industrial success.
"The main challenge we faced was to scale up the process," Illy reveals. "[It had to be] consistent and safe to be carried out by a trained technician, not a specialist PhD as was the case in the beginning."
They recruited a team of scientists to help them develop a more effective and robust manufacturing process. Together, the team gained a more detailed theoretical understanding about what was happening at each stage of the chemical reactions. Eventually, they were able to fine tune the process and produce consistent batches of polyester.
They're making significant progress. They've produced their first samples and signed their first commercial contract to make polyester, which will then be both fabricated into clothes and sold by partner companies.
Currently, one of the largest challenges is financial. "We need to raise a fair amount to buy the equipment we need to produce at a large scale," Illy explains.
How to Power the Process?
At the moment, their main scientific focus is getting the process working reliably so they can begin commercialization. In order to remain sustainable and economically viable once they start producing polyester on a large scale, they need to consider the amount of energy they use for carbon valorization and the emissions they produce.
The more they optimize the way their catalyst works, the easier it will be to transform the CO2. The whole process can then become more cost effective and energy efficient.
De Luna explains: "My concern is...whether their process will be economical at scale. The problem is the energy cost to take carbon dioxide and transform it into these other products and that's where the science and innovation has to happen. [Whether they can scale up economically] depends on the performance of their catalyst."
They don't just need to think about the amount of energy they use to produce polyester; they also have to consider where this energy comes from.
"They need access to cheap renewable energy," De Luna says, "...so they're not using or emitting CO2 to do the conversion." If the energy they use to transform CO2 into polyester actually ends up producing more CO2, this will end up cancelling out their positive environmental impact.
Based in France, they're well located to address this issue. France has a clean electricity system, with only about 10% of their electric power coming from fossil fuels due to their reliance on nuclear energy and renewables.
Where Do They Get the Carbon Dioxide?
As they scale up, they also need to be able to access a source of CO2. They intend to obtain this from the steel industry, the cement industry, and hydrogen production.
The technology to purify and capture waste carbon dioxide from these industries is available on a large scale. However, there are only around 20 commercial operations in the world. The high cost of carbon capture means that development continues to be slow. There are a growing number of startups capturing carbon dioxide straight from the air, but this is even more costly.
One major problem is that storing captured carbon dioxide is expensive. "There are somewhat limited options for permanently storing captured CO2, so innovations like this are important,'' says T. Reed Miller, a researcher at the Yale University Center for Industrial Ecology.
Illy says: "The challenge is now to decrease the cost [of carbon capture]. By using CO2 as a raw material, we can try to increase the number of industries that capture CO2. Our goal is to turn CO2 from a waste into a valuable product."
Beyond Fashion
For Nasr Allah and Illy, fashion is just the beginning. There are many markets they can potentially break into. Next, they hope to use the polyester they've created in the packaging industry. Today, a lot of polyester is consumed to make bottles and jars. Illy believes that eventually they can produce many different chemicals from CO2. These chemicals could then be used to make paints, adhesives, and even plastics.
The Fairbrics scientists are providing a vital alternative to fossil fuels and showcasing the real potential of carbon dioxide to become a worthy resource instead of a harmful polluter.
Illy believes they can make a real difference through innovation: "We can have a significant impact in reducing climate change."
Your phone could show if a bridge is about to collapse
In summer 2017, Thomas Matarazzo, then a postdoctoral researcher at the Massachusetts Institute of Technology, landed in San Francisco with a colleague. They rented two cars, drove up to the Golden Gate bridge, timing it to the city’s rush hour, and rode over to the other side in heavy traffic. Once they reached the other end, they turned around and did it again. And again. And again.
“I drove over that bridge 100 times over five days, back and forth,” says Matarazzo, now an associate director of High-Performance Computing in the Center for Innovation in Engineering at the United States Military Academy, West Point. “It was surprisingly stressful, I never anticipated that. I had to maintain the speed of about 30 miles an hour when the speed limit is 45. I felt bad for everybody behind me.”
Matarazzo had to drive slowly because the quality of data they were collecting depended on it. The pair was designing and testing a new smartphone app that could gather data about the bridge’s structural integrity—a low-cost citizen-scientist alternative to the current industrial methods, which aren’t always possible, partly because they’re expensive and complex. In the era of aging infrastructure, when some bridges in the United States and other countries are structurally unsound to the point of collapsing, such an app could inform authorities about the need for urgent repairs, or at least prompt closing the most dangerous structures.
There are 619,588 bridges in the U.S., and some of them are very old. For example, the Benjamin Franklin Bridge connecting Philadelphia to Camden, N.J., is 96-years-old while the Brooklyn Bridge is 153. So it’s hardly surprising that many could use some upgrades. “In the U.S., a lot of them were built in the post-World War II period to accommodate the surge of motorization,” says Carlo Ratti, architect and engineer who directs the Senseable City Lab at Massachusetts Institute of Technology. “They are beginning to reach the end of their life.”
According to the 2022 American Road & Transportation Builders Association’s report, one in three U.S. bridges needs repair or replacement. The Department of Transportation (DOT) National Bridge Inventory (NBI) database reveals concerning numbers. Thirty-six percent of U.S. bridges need repair work and over 78,000 bridges should be replaced. More than 43,500 bridges are rated in poor condition and classified as “structurally deficient” – an alarming description. Yet, people drive over them 167.5 million times a day. The Pittsburgh bridge which collapsed in January this year—only hours before President Biden arrived to discuss the new infrastructure law—was on the “poor” rating list.
Assessing the structural integrity of a bridge is not an easy endeavor. Most of the time, these are visual inspections, Matarazzo explains. Engineers check cracks, rust and other signs of wear and tear. They also check for wildlife—birds which may build nests or even small animals that make homes inside the bridge structures, which can slowly chip at the structure. However, visual inspections may not tell the whole story. A more sophisticated and significantly more expensive inspection requires placing special sensors on the bridge that essentially listen to how the bridge vibrates.
“Some bridges can afford expensive sensors to do the job, but that comes at a very high cost—hundreds of thousands of dollars per bridge per year,” Ratti says.
We may think of bridges as immovable steel and concrete monoliths, but they naturally vibrate, oscillating slightly. That movement can be influenced by the traffic that passes over them, and even by wind. Bridges of different types vibrate differently—some have longer vibrational frequencies and others shorter ones. A good way to visualize this phenomenon is to place a ruler over the edge of a desk and flick it slightly. If the ruler protrudes far off the desk, it will vibrate slowly. But if you shorten the end that hangs off, it will vibrate much faster. It works similarly with bridges, except there are more factors at play, including not only the length, but also the design and the materials used.
The long suspension bridges such as the Golden Gate or Verrazano Narrows, which hang on a series of cables, are more flexible, and their vibration amplitudes are longer. The Golden Gate Bridge can vibrate at 0.106 Hertz, where one Hertz is one oscillation per second. “Think about standing on the bridge for about 10 seconds—that's how long it takes for it to move all the way up and all the way down in one oscillation,” Matarazzo says.
On the contrary, the concrete span bridges that rest on multiple columns like Brooklyn Bridge or Manhattan Bridge, are “stiffer” and have greater vibrational frequencies. A concrete bridge can have a frequency of 10 Hertz, moving 10 times in one second—like that shorter stretch of a ruler.
The special devices that can pick up and record these vibrations over time are called accelerometers. A network of these devices for each bridge can cost $20,000 to $50,000, and more—and require trained personnel to place them. The sensors also must stay on the bridge for some time to establish what’s a healthy vibrational baseline for a given bridge. Maintaining them adds to the cost. “Some bridges can afford expensive sensors to do the job, but that comes at a very high cost—hundreds of thousands of dollars per bridge per year,” Ratti says.
Making sense of the readouts they gather is another challenge, which requires a high level of technical expertise. “You generally need somebody, some type of expert capable of doing the analysis to translate that data into information,” says Matarazzo, which ticks up the price, so doing visual inspections often proves to be a more economical choice for state-level DOTs with tight budgets. “The existing systems work well, but have downsides,” Ratti says. The team thought the old method could use some modernizing.
Smartphones, which are carried by millions of people, contain dozens of sensors, including the accelerometers capable of picking up the bridges’ vibrations. That’s why Matarazzo and his colleague drove over the bridge 100 times—they were trying to pick up enough data. Timing it to rush hour supported that goal because traffic caused more “excitation,” Matarazzo explains. “Excitation is a big word we use when we talk about what drives the vibration,” he says. “When there's a lot of traffic, there's more excitation and more vibration.” They also collaborated with Uber, whose drivers made 72 trips across the bridge to gather data in different cars.
The next step was to clean the data from “noise”—various vibrations that weren’t relevant to the bridge but came from the cars themselves. “It could be jumps in speed, it could be potholes, it could be a bunch of other things," Matarazzo says. But as the team gathered more data, it became easier to tell the bridge vibrational frequencies from all others because the noises generated by cars, traffic and other things tend to “cancel out.”
The team specifically picked the Golden Gate bridge because the civil structural engineering community had studied it extensively over the years and collected a host of vibrational data, using traditional sensors. When the researchers compared their app-collected frequencies with those gathered by 240 accelerometers formerly placed on the Golden Gate, the results were the same—the data from the phones converged with that from the bridge’s sensors. The smartphone-collected data were just as good as those from industry devices.
The study authors estimate that officials could use crowdsourced data to make key improvements that would help new bridges to last about 14 years longer.
The team also tested their method on a different type of bridge—not a suspension one like the Golden Gate, but a concrete span bridge in Ciampino, Italy. There they compared 280 car trips over the bridge to the six sensors that had been placed on the bridge for seven months. The results were slightly less matching, but a larger volume of trips would fix the divergence, the researchers wrote in their study, titled Crowdsourcing bridge dynamic monitoring with smartphone vehicle trips, published last month in Nature Communications Engineering.
Although the smartphones proved effective, the app is not quite ready to be rolled out commercially for people to start using. “It is still a pilot version,” so there’s room for improvement, says Ratti, who co-authored the study. “But on a more optimistic note, it has really low barriers to entry—all you need is smartphones on cars—so that makes the system easy to reach a global audience.” And the study authors estimate that the use of crowdsourced data would result in a new bridge lasting about 14 years longer.
Matarazzo hopes that the app could be eventually accessible for your average citizen scientist to collect the data and supply it to their local transportation authorities. “I hope that this idea can spark a different type of relationship with infrastructure where people think about the data they're collecting as some type of contribution or investment into their communities,” he says. “So that they can help their own department of transportation, their own municipality to support that bridge and keep it maintained better, longer and safer.”
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.
The Friday Five: Sugar could help catch cancer early
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.
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Here are the promising studies covered in this week's Friday Five:
- Catching cancer early could depend on sugar
- How to boost memory in a flash
- This is your brain on books
- A tiny sandwich cake could help the heart
- Meet the top banana for fighting Covid variants