Like the lead paint and asbestos of decades past, microplastics are the new awful contaminant that we really ought to do something about. They’re particularly abundant in the aquatic environment, and that’s not a good thing. While we’ve all seen heartbreaking photos of beaches strewn with water bottles and fishing nets, it’s the invisible threat that keeps environmentalists up at night. We’re talking about microplastics – those tiny fragments that are quietly infiltrating every corner of our oceans.
We’ve dumped billions of tons of plastic waste into our environment, and all that waste breaks down into increasingly smaller particles that never truly disappear. Now, scientists are turning to an unexpected solution to clean up this pollution with the aid of seashells and plants.
Sticky Solution
A team of researchers has developed what amounts to a fancy sponge for sucking up microplastics, made using readily available natural materials—chitin from marine creatures, and cellulose from plants. When these materials are processed just right, they form a super-porous foam that readily “adsorbs” microplastic material, removing it from the water. If you’re not familiar with the term, adsorbtion is simple—it refers to material clinging on to the surface of a solid, rather than being absorbed into it.
To create the material, researchers took chitin and cellulose, and broke down the natural hydrogen bonds in both materials, which allowed them to be reconstructed into a new foam-like form. The result is a very porous material that has negatively- and positively-charged areas on the surface that can effectively bond with microplastic particles. Indeed, the foam effectively grabs plastic particles through a combination of electrostatic attraction, physical entrapment, and other intramolecular forces. It both attracts microplastics via physical forces and entangles them, too.
The foam performed well in testing, capturing from 98% to 99.9% of microplastics. Even more impressive, the foam maintained a removal efficiency above 95% even after five usage cycles, a positive sign for its practical longevity. The material shows particular affinity for common plastics that show up in litter and other waste streams—like polystyrene, polypropylene, polyethylene terephthalate (PET) and polymethyl methacrylate (PMMA).
Of course, polluted water on Earth is a more complex mix than just water and plastic. Take a sample and you’re going to find lots of organic matter, bacteria, and other pollutants mixed in. The researchers put their foam through its paces with four different samples from real-world contexts—taken from agriculture irrigation, lake waters, still water, and coastal waters. While contaminants like ethanol and methylene blue cut the adsorption capacity of the foam by up to 50%, that wasn’t the case all round. Surprisingly, some contaminants actually improved its performance. When heavy metals like lead were present, the foam’s plastic-capturing ability increased, and it gained a similar benefit from the presence of bacteria like e.Coli. Testing like this is crucial for proving the foam’s viability outside of simple laboratory tests. Removing plastic from clean water is one thing; removing it from real samples is another thing entirely.
The beauty of this approach lies in its simplicity and accessibility. Unlike some high-tech solutions requiring expensive materials or complex manufacturing, the foam is made out of materials that can be sourced in abundance. Chitin is readily available from seafood processing waste, and cellulose can be sourced from agricultural byproducts. The research paper also explains the basic methods of preparing the hybrid foam material, which are well within the abilities of any competent lab and chemical engineer.
While this foam won’t single-handedly solve our ocean plastic crisis, it represents a promising direction in environmental remediation. The challenge now lies in scaling up production and developing practical deployment methods for real-world conditions. Developing the foam was step one—the next step involves figuring out how to actually put it to good use to sieve the oceans clean. Stopping plastic contamination at the source is of course the ideal, but for all the plastic that’s already out there, there’s still a lot to be done.
Featured image: “Microplastic” by Oregon State University
We could build a truly massive parallel facility of centrifugae (say the size of Los Santos) that would remove microplastics leaving behind water. It could also be used to extract minute quantities of uranium from seawater so that we may finally embrace the new era of affordable nuclear power.
how do you propose we separate the undesirable particulate and the nuclear particles you desire from the microorganisms that are essential to the food chain
There’s this funny property of organisms… They tend to make more of themselves, without human intervention (sometimes despite it).
Sure but my point is that filtering the entire ocean through centrifuges is going to have some indeterminate effects on the ecosystem to say nothing of the enormous power requirement and subsequent pollution that would cause.
“The size of Los Santos”… You are aware Los Santos is entirely fictional right? It doesn’t have a size (other than a bit/byte count)
Who is “we”?
” scaling up production and developing practical deployment methods for real-world conditions.” . Those are engineering problems, to be solved by engineering.
The lingering problem, not easily solved and conveniently ignored : Who will pay for all of this ?
Well, if they get it working for plastics, now make it work for useful stuff, like all the lithium, uranium, deuterium, gold, copper, etc. They are all present in far greater concentrations in seawater than microplastics, but currently economically not worthwhile to extract. Maybe what they are learning here will help avoid the mess we make when we extract such goodies from dry dirt.
Then again, maybe we will learn that the making the energy required to collect all those microplastics costs the environment far more than just leaving the stuff in place to get removed by natural processes.
I’d submit that captured plastic particles -are- “useful stuff.” Feed it into a pyrolysis rig and recover light crude. Since the oil is the outcome of processing existing material, unlike pumping crude from the ground, it is in effect carbon neutral.
Except it will cost more in energy to extract it from the water than you would ever recover by burning it. It will also cost more (in energy, money, or environmental impact) to extract it from water than it would to get that “light crude” by other means.
As a saleable byproduct, perhaps reprocessing it is preferable to landfill, but I doubt it’s a net win, environmentally.
Really, if you want the material, catch it before it gets dispersed in the water.
Sounds slightly faster than letting dead fish drag the pollutants to the bottom of the ocean. We could release it in mass quantities off the coast of China :)
Already happening, in case you didn’t notice.
Also, FWIW, that paper is entirely Chinese-authored research.
What’s with the goofy “Little Prince” tiny planet circular bar graph? What a confusing way to present eight simple numbers.
Something is going to start eating that stuff pretty soon. Probably more than one thing. There’s too much energy to be had for life not to exploit it. It’ll be like when fungi figured out how to digest cellulose.
Not sure what that’ll do, mind you, and it may not be good at all…
A bit of a rant.
I appreciate the efforts. Every possible solution should be investigated. I doubt (I really hope I’m wrong) that this won’t work on the scale needed to actually filter out micro plastics, but if there is a chance, it’s worthwhile research. In the past I’ve done some work for the ocean cleanup project and currently I work for a company that’s doing environmental research.
Cleaning it up is great, but stopping the pollution coming in is a disaster by itself. You might think that plastic bags, bottles and straws might be a huge problem, but that’s just a drop in the bucket. The vast majority (depending on research referenced, between 60 and 72%) of plastics in the oceans are fishing nets. These are bottom trawling nets that can easily get caught on something on the bottom of the ocean, resulting in the net to be lost. These nets are incredibly large and this is an extremely common thing to happen. Depending on the source used, the estimates for the biggest country that uses this method is between half a million to well over a million fishing vessels. Sadly, I only know of three countries (Greece, Sweden and Chile) that banned the use of these nets.
Another portion comes from natural disasters. Hurricanes, tsunami’s and other floods bring a lot of debris into the oceans.
There is a lot of waste being dumped into rivers, sadly, but that’s a tiny portion of the plastics in the ocean. We, and many of our business comrades, are working on finding solutions to lower that last part. Special nets in rivers that don’t limit the movement of vessels, reroutes of rivers with filtration, drain pipe filtration and other methods that could limit the waste in highly polluted rivers. But even that is sadly not the end all solution to these problems.
I wish we had good quality materials that are cheaper than plastics, especially for fishing nets.
I throw my car batteries in the ocean to help soak up the microplastics.