Sparklers produce a beautiful display of light and heat by burning metal dust, which contains iron. The recent work of Canadian and Dutch researchers suggests we can use iron as a cheap, carbon-free fuel.
Story by Freethink
Try burning an iron metal ingot and you’ll have to wait a long time — but grind it into a powder and it will readily burst into flames. That’s how sparklers work: metal dust burning in a beautiful display of light and heat. But could we burn iron for more than fun? Could this simple material become a cheap, clean, carbon-free fuel?
In new experiments — conducted on rockets, in microgravity — Canadian and Dutch researchers are looking at ways of boosting the efficiency of burning iron, with a view to turning this abundant material — the fourth most common in the Earth’s crust, about about 5% of its mass — into an alternative energy source.
Iron as a fuel
Iron is abundantly available and cheap. More importantly, the byproduct of burning iron is rust (iron oxide), a solid material that is easy to collect and recycle. Neither burning iron nor converting its oxide back produces any carbon in the process.
Iron oxide is potentially renewable by reacting with electricity or hydrogen to become iron again.
Iron has a high energy density: it requires almost the same volume as gasoline to produce the same amount of energy. However, iron has poor specific energy: it’s a lot heavier than gas to produce the same amount of energy. (Think of picking up a jug of gasoline, and then imagine trying to pick up a similar sized chunk of iron.) Therefore, its weight is prohibitive for many applications. Burning iron to run a car isn’t very practical if the iron fuel weighs as much as the car itself.
In its powdered form, however, iron offers more promise as a high-density energy carrier or storage system. Iron-burning furnaces could provide direct heat for industry, home heating, or to generate electricity.
Plus, iron oxide is potentially renewable by reacting with electricity or hydrogen to become iron again (as long as you’ve got a source of clean electricity or green hydrogen). When there’s excess electricity available from renewables like solar and wind, for example, rust could be converted back into iron powder, and then burned on demand to release that energy again.
However, these methods of recycling rust are very energy intensive and inefficient, currently, so improvements to the efficiency of burning iron itself may be crucial to making such a circular system viable.
The science of discrete burning
Powdered particles have a high surface area to volume ratio, which means it is easier to ignite them. This is true for metals as well.
Under the right circumstances, powdered iron can burn in a manner known as discrete burning. In its most ideal form, the flame completely consumes one particle before the heat radiating from it combusts other particles in its vicinity. By studying this process, researchers can better understand and model how iron combusts, allowing them to design better iron-burning furnaces.
Discrete burning is difficult to achieve on Earth. Perfect discrete burning requires a specific particle density and oxygen concentration. When the particles are too close and compacted, the fire jumps to neighboring particles before fully consuming a particle, resulting in a more chaotic and less controlled burn.
Presently, the rate at which powdered iron particles burn or how they release heat in different conditions is poorly understood. This hinders the development of technologies to efficiently utilize iron as a large-scale fuel.
Burning metal in microgravity
In April, the European Space Agency (ESA) launched a suborbital “sounding” rocket, carrying three experimental setups. As the rocket traced its parabolic trajectory through the atmosphere, the experiments got a few minutes in free fall, simulating microgravity.
One of the experiments on this mission studied how iron powder burns in the absence of gravity.
In microgravity, particles float in a more uniformly distributed cloud. This allows researchers to model the flow of iron particles and how a flame propagates through a cloud of iron particles in different oxygen concentrations.
Existing fossil fuel power plants could potentially be retrofitted to run on iron fuel.
Insights into how flames propagate through iron powder under different conditions could help design much more efficient iron-burning furnaces.
Clean and carbon-free energy on Earth
Various businesses are looking at ways to incorporate iron fuels into their processes. In particular, it could serve as a cleaner way to supply industrial heat by burning iron to heat water.
For example, Dutch brewery Swinkels Family Brewers, in collaboration with the Eindhoven University of Technology, switched to iron fuel as the heat source to power its brewing process, accounting for 15 million glasses of beer annually. Dutch startup RIFT is running proof-of-concept iron fuel power plants in Helmond and Arnhem.
As researchers continue to improve the efficiency of burning iron, its applicability will extend to other use cases as well. But is the infrastructure in place for this transition?
Often, the transition to new energy sources is slowed by the need to create new infrastructure to utilize them. Fortunately, this isn’t the case with switching from fossil fuels to iron. Since the ideal temperature to burn iron is similar to that for hydrocarbons, existing fossil fuel power plants could potentially be retrofitted to run on iron fuel.
This article originally appeared on Freethink, home of the brightest minds and biggest ideas of all time.
Many children use makeup and body products such as glitter, face paint and lip gloss. Scientists are pointing to the harmful chemicals in some of these products, and advocates are looking to outlaw them.
In 2013, Toxic-Free Future launched Mind the Store to challenge the nation’s largest retailers in adopting comprehensive policies that eliminate toxic chemicals in their personal care products and packaging, and develop safer alternatives.
Now, more efforts are underway to expose and mitigate the harm in cosmetics, hair care and other products that children apply on their faces, heads, nails and other body parts. Advocates hope to raise awareness among parents while prompting manufacturers and salon professionals to adopt safer alternatives.
A recent study by researchers at Columbia University Mailman School of Public Health and Earthjustice, a San Francisco-based nonprofit public interest environmental law organization, revealed that most children in the United States use makeup and body products that may contain carcinogens and other toxic chemicals. In January, the results were published in the International Journal of Environmental Research and Public Health. Based on more than 200 surveys, 70 percent of parents in the study reported that their children 12 or younger have used makeup and body products marketed to youth — for instance, glitter, face paint and lip gloss.
Childhood exposure to harmful makeup and body product ingredients can also be considered an environmental justice issue, as communities of color may be more likely to use these products.
“We are concerned about exposure to chemicals that may be found in cosmetics and body products, including those that are marketed toward children,” said the study’s senior author, Julie Herbstman, a professor and director of the Columbia Center for Children's Environmental Health. The goal of the survey was to try to understand how much kids are using cosmetic and body products and when, how and why they are using them.
“There is widespread use of children’s cosmetic and body products, and kids are using them principally to play,” Herbstman said. “That’s really quite different than how adults use cosmetic and body products.” Even with products that are specifically designed for children, “there’s no regulation that ensures that these products are safe for kids.” Also, she said, some children are using adult products — and they may do so in inadvisable ways, such as ingesting lipstick or applying it to other areas of the face.
Earlier research demonstrated that beauty and personal care products manufactured for children and adults frequently contain toxic chemicals, such as lead, asbestos, PFAS, phthalates and formaldehyde. Heavy metals and other toxic chemicals in children’s makeup and body products are particularly harmful to infants and youth, who are growing rapidly and whose bodies are less efficient at metabolizing these chemicals. Whether these chemicals are added intentionally or are present as contaminants, they have been associated with cancer, neurodevelopmental harm, and other serious and irreversible health effects, the Columbia University and Earthjustice researchers noted.
“Even when concentrations of individual chemicals are low in products, the potential for interactive effects from multiple toxicants is important to take into consideration,” the authors wrote in the journal article. “Allergic reactions, such as contact dermatitis, are some of the most frequently cited negative health outcomes associated with the use of cosmetics.”
Children’s small body side, rapid growth rate and immature immune systems are biologically more prone to the effects of toxicants than adults.
Adobe Stock
In addition to children’s rapid growth rate, the study also reported that their small body size, developing tissues and organs, and immature immune systems are biologically more prone to the effects of toxicants than adults. Meanwhile, the study noted, “childhood exposure to harmful makeup and body product ingredients can also be considered an environmental justice issue, as communities of color may be more likely to use these products.”
Although adults are the typical users of cosmetics, similar items are heavily marketed to youth with attention-grabbing features such as bright colors, animals and cartoon characters, according to the study. Beyond conventional makeup such as eyeshadow and lipstick, children may apply face paint, body glitter, nail polish, hair gel and fragrances. They also may frequent social media platforms on which these products are increasingly being promoted.
Products for both children and adults are currently regulated by the U.S. Food and Drug Administration under the Federal Food, Drug, and Cosmetic Act of 1938. Also, the Fair Packaging and Labeling Act of 1967 directs the Federal Trade Commission and the FDA “to issue regulations requiring that all ‘consumer commodities’ be labeled to disclose net contents, identity of commodity, and name and place of business of the product's manufacturer, packer, or distributor.” As the Columbia University and Earthjustice authors pointed out, though, “current safety regulations have been widely criticized as inadequate.”
The Personal Care Products Council in Washington, D.C., “fundamentally disagrees with the premise that companies put toxic chemicals in products produced for children,” industry spokeswoman Lisa Powers said in an email. Founded in 1894, the national trade association represents 600 member companies that manufacture, distribute and supply most personal care products marketed in the United States.
No category of consumer products is subject to less government oversight than cosmetics and other personal care products. -- Environmental Working Group.
“Science and safety are the cornerstones of our industry,” Powers stated. For more than a decade, she wrote, “the [Council] and our member companies worked diligently with a bipartisan group of congressional leaders and a diverse group of stakeholders to enhance the effectiveness of the FDA regulatory authority and to provide the safety reassurances that consumers expect and deserve.”
Powers added that the “industry employs and consults thousands of scientific and medical experts” who study the impacts of cosmetics and personal care products and the ingredients used in them. The Council also maintains a comprehensive database where consumers can look up science and safety information on the thousands of ingredients in sunscreens, toothpaste, shampoo, moisturizer, makeup, fragrances and other products.
However, the Environmental Working Group, which empowers consumers with breakthrough research to make informed choices about healthy living, believes the regulations are still not robust enough. “No category of consumer products is subject to less government oversight than cosmetics and other personal care products,” states the organization’s website. “Although many of the chemicals and contaminants in cosmetics and personal care products likely pose little risk, exposure to some has been linked to serious health problems, including cancer.”
The group, which operates the Skin Deep Database noted that “since 2009, 595 cosmetics manufacturers have reported using 88 chemicals, in more than 73,000 products, that have been linked to cancer, birth defects or reproductive harm.”
But change, for both adults and kids, is on the horizon. The Modernization of Cosmetics Regulation Act of 2022 significantly expanded the FDA’s authority to regulate cosmetics. In May 2023, Washington state adopted a law regulating cosmetics and personal care products. The Toxic-Free Cosmetics Act (HB 1047) bans chemicals in beauty and personal care products, such as PFAS, lead, mercury, phthalates and formaldehyde-releasing agents. These bans take effect in 2025, except for formaldehyde releasers, which have a phased-in approach starting in 2026.
Industry and advocates view this as a positive development. Powers, the spokesperson, praised “the long-awaited” Modernization Cosmetics Regulation Act of 2022, which she said, “advances product safety and innovation.” Jen Lee, chief impact officer at Beautycoutner, a company that sells personal care products, also welcomes the change. “We were proud to support the Washington Toxic-Free Cosmetics Act (HB 1047) by mobilizing our community of Brand Advocates who reside in Washington State,” Lee said. “Together, they made their voices heard by sending over 1,000 emails to their state legislators urging them to support and pass the bill.”
Laurie Valeriano, executive director of Toxic-Free Future, praised the upcoming Washington state law as “a huge win for public health and the environment that will have impacts that ripple across the nation.” She added that “companies won’t make special products for Washington state.” Instead, “they will reformulate and make products safer for everyone” — adults and children.
You shouldn’t have to be a toxicologist to shop for shampoo. -- Washington State Rep. Sharlett Mena
The new legislation will require Washington state agencies to assess the hazards of chemicals used in products that can impact vulnerable populations, while providing support for small businesses and independent cosmetologists to transition to safer products.
The Toxic-Free Future team lauds the Cosmetics Act, signed in May 2023.
Courtesy Toxic-Free Future
“When we go to a store, we assume the products on the shelf are safe, but this isn’t always true,” said Washington State Rep. Sharlett Mena, a Democrat serving in the 29th Legislative District (Tacoma), who sponsored the law. “I introduced this bill (HB 1047) because currently, the burden is on the consumer to navigate labels and find safe alternatives. You shouldn’t have to be a toxicologist to shop for shampoo.”
The new law aims to protect people of all ages, but especially youth. “Children are more susceptible to the impacts of toxic chemicals because their bodies are still developing,” Mena said. “Lead, for example, is significantly more hazardous to children than adults. Also, since children, unlike adults, tend to put things in their mouths all the time, they are more exposed to harmful chemicals in personal care and other products.”
Cosmetologists and hair professionals are taking notice. “Safety should be the practitioner’s number one concern” in using products on small children, said Anwar Saleem, a hair stylist, instructor and former salon owner in Washington, D.C., who is chairman of the D.C. Board of Barbering and Cosmetology and president of the National Interstate Council of State Boards of Cosmetology. “There are so many products on the market that it can be confusing.”
Hair products designed and labeled for children's use often have milder formulations, but “every child is unique, and what works for one may not work for another,” Saleem said. He recommends doing a patch test, in which the stylist or cosmetologist dabs the product on a small, inconspicuous area of the scalp or skin and waits anywhere from an hour to a day to check for irritation before continuing to serve the client. “Performing a patch test, observing children's reactions to a product and adequately adjusting are essential.”
Saleem seeks products that are free from harsh chemicals such as sulfates, phthalates and parabens, noting that these ingredients can be irritating and drying to the hair and scalp. If a child has sensitive skin or allergies, Saleem opts for hypoallergenic products.
We also need to ensure that less toxic alternatives are available and accessible to all consumers. It’s often under-resourced, low-income populations who suffer the burden of environmental exposures and do not have access or cannot afford these safer alternatives. -- Lesliam Quirós-Alcalá.
Lesliam Quirós-Alcalá, an assistant professor in the department of environmental health and engineering at the Johns Hopkins Bloomberg School of Public Health, said current regulatory loopholes on product labeling still allow manufacturers to advertise their cosmetics and personal care products as “gentle” and “natural.” However, she said, those terms may be misleading as they don’t necessarily mean the contents are less toxic or harmful to consumers.
“We also need to ensure that less toxic alternatives are available and accessible to all consumers,” Quirós-Alcalá said, “as often alternatives considered to be less toxic come with a hefty price tag.” As a result, “it’s often under-resourced, low-income populations who suffer the burden of environmental exposures and do not have access or cannot afford these safer alternatives.”
To advocate for safer alternatives, Quirós-Alcalá suggests that parents turn to consumer groups involved in publicizing the harms of personal care products. The Campaign for Safe Cosmetics is a program of Breast Cancer Prevention Partners, a national science-based advocacy organization aiming to prevent the disease by eliminating related environmental exposures. Other resources that inform users about unsafe ingredients include the mobile apps Clearya and Think Dirty.
“Children are not little adults, so it’s important to increase parent and consumer awareness to minimize their exposures to toxic chemicals in everyday products,” Quirós-Alcalá said. “Becoming smarter, more knowledgeable consumers is the first step to protecting your family from potentially harmful and toxic ingredients in consumer products.”
A company is looking to improve medicines by making them in the nearly weightless environment of space.
Microgravity research could potentially lead to many more discoveries like this one, or even the development of brand-new drugs, but ISS astronauts only have so much time for commercial experiments.
“There are many high-performance products that are only possible to make in zero-gravity, which is a manufacturing capability that cannot be replicated in any factory on Earth.”-- Will Bruey.
The only options for accessing microgravity (or free fall) outside of orbit, meanwhile, are parabolic airplane flights and drop towers, and those are only useful for experiments that require less than a minute in microgravity — Merck’s ISS experiment took 18 days.
The idea: In 2021, California startup Varda Space Industries announced its intention to build the world’s first space factory, to manufacture not only pharmaceuticals but other products that could benefit from being made in microgravity, such as semiconductors and fiber optic cables.
This factory would consist of a commercial satellite platform attached to two Varda-made modules. One module would contain equipment capable of autonomously manufacturing a product. The other would be a reentry capsule to bring the finished goods back to Earth.
“There are many high-performance products that are only possible to make in zero-gravity, which is a manufacturing capability that cannot be replicated in any factory on Earth,” said CEO Will Bruey, who’d previously developed and flown spacecraft for SpaceX.
“We have a team stacked with aerospace talent in the prime of their careers, focused on getting working hardware to orbit as quickly as possible,” he continued.
“[Pharmaceuticals] are the most valuable chemicals per unit mass. And they also have a large market on Earth.” -- Will Bruey, CEO of Varda Space.
What’s new? At the time, Varda said it planned to launch its first space factory in 2023, and, in what feels like a first for a space startup, it has actually hit that ambitious launch schedule.
“We have ACQUISITION OF SIGNAL,” the startup tweeted soon after the Falcon 9 launch on June 12. “The world’s first space factory’s solar panels have found the sun and it’s beginning to de-tumble.”
During the satellite’s first week in space, Varda will focus on testing its systems to make sure everything works as hoped. The second week will be dedicated to heating and cooling the old HIV-AIDS drug ritonavir repeatedly to study how its particles crystalize in microgravity.
After about a month in space, Varda will attempt to bring its first space factory back to Earth, sending it through the atmosphere at hypersonic speeds and then using a parachute system to safely land at the Department of Defense’s Utah Test and Training Range.
Looking ahead: Ultimately, Varda’s space factories could end up serving dual purposes as manufacturing facilities and hypersonic testbeds — the Air Force has already awarded the startup a contract to use its next reentry capsule to test hardware for hypersonic missiles.
But as for manufacturing other types of goods, Varda plans to stick with drugs for now.
“[Pharmaceuticals] are the most valuable chemicals per unit mass,” Bruey told CNN. “And they also have a large market on Earth.”
“You’re not going to see Varda do anything other than pharmaceuticals for the next minimum of six, seven years,” added Delian Asparouhov, Varda’s co-founder and president.
This article originally appeared on Big Think, home of the brightest minds and biggest ideas of all time.
