Polystyrene waste

[RickB]

https://phys.org/news/2021-03-polystyre ... tists.html
Polystyrene waste is everywhere, and it's not biodegradable. Scientists just found a way to break it down.

Scientists at the U.S. Department of Energy's Ames Laboratory and their partners from Clemson University have discovered a green, low-energy process to break down polystyrene, a type of plastic that is widely used in foam packaging materials, disposable food containers, cutlery, and many other applications.

Polystyrene is part of a much larger global plastic waste problem. Hundreds of millions metric tons of polymers are produced each year, a large majority of which is discarded after use. Due to the chemical stability and durability of industrial polymers, plastic waste does not easily degrade in landfills and is often burned, which produces carbon dioxide and other hazardous gases. In order to stop the growing flood of polymer waste and reduce carbon dioxide emissions, plastics have to be recycled or converted into new value-added products

Currently, recycling of the vast majority of plastics is not economically feasible; their sorting and separation are time and labor intensive, while chemical processing and remanufacturing requires a significant energy input and toxic solvents. Re-processed polymers often show inferior performance to that of the freshly manufactured "made from scratch" materials.

A team of scientists at Ames Laboratory used processing by ball-milling to deconstruct commercial polystyrene in a single step, at room temperature, in ambient atmosphere in the absence of harmful solvents. Ball-milling is a technique that places materials in a milling vial with metal ball bearings which is then agitated until a desired chemical reaction occurs. Called mechanochemistry, this experimental approach has numerous applications in new materials synthesis, and attractive features where plastics recycling is concerned.

The deconstruction of polystyrene proceeds through a series of chemical events involving mechanical cutting apart of the macromolecules, which generates free radicals detectable in the milled material even after its prolonged exposure to air. The metal bearings used for milling and the ambient oxygen act as co-catalysts that enable extraction of the monomeric styrene from the oligomeric radical-bearing species formed. The experiments showed that the temperature rise in the material during milling is not responsible for the observed phenomenon since the temperature inside the milled powder does not exceed 50oC while the thermal decomposition of polystyrene in air starts at about 325oC. The Clemson's group confirmed the comprehensive deconstruction of the original polymer into smaller fragments, oligomeric materials, suitable for further processing into new value-added products.

"This method represents an important breakthrough that enables dismantling of a polymer simultaneously with its break-down under ambient conditions, that is, ~300 C below the thermal decomposition temperature of the pristine material" said Ames Laboratory Senior Scientist Viktor Balema. "We think this proof of concept is an exciting possibility for developing new recycling technologies for all kinds of plastics, and that will contribute to establishment of the circular economy."

His partner from Clemson University, Kentwool Distinguished Professor Igor Luzinov, further commented that "this discovery opens new avenues for low temperature recovery of monomers from multicomponent polymer based systems such as composites and laminates. Also, our technology will allow extracting the monomer from crosslinked materials containing styrene units in their structures."

Alfred P. Sloan Foundation Research Fellow, Professor Aaron Rossini of Iowa State University, further noted that "electron paramagnetic resonance spectroscopy shows large concentrations of free radical carbon-centered species in polystyrene that was milled in air. This is a startling result because free radicals are normally very reactive. Also, the presence of the radicals gives direct evidence that the milling directly causes scission of the polymer chains. We expect that the reactive sites associated with the free radicals can be used to functionalize the processed polymers to obtain new value-added products."

The research is further discussed in the paper "Depolymerization of polystyrene under ambient conditions," authored by Viktor P. Balema, Ihor Z. Hlova, Scott L. Carnahan, Mastooreh Seyedi, Oleksandr Dolotko, Aaron J. Rossini, and Igor Luzinov; featured on the front cover of the New Journal of Chemistry.

[mattpeneguy]

For disposing of polystyrene, just put it out in sunlight....Most of our plastics break down by themselves. We just need a better means of containing it and letting mother nature do what she does. The convoluted things we try usually have unintended consequences that we then have to deal with, too.

Ooh, I have a better idea! Since Musk has made launching things into orbit so much cheaper, let's just launch all of that plastic up there! We need a task force for ideas like this, I nominate Mike Judge (Idiocracy, for those that don't know/remember).

[Roasted By John]

I would still like to try out the Granulator that we built to granulate old tires, in the plastic bottle recycling process...

The patent is expired...

image.png

[mattpeneguy]

I would still like to try out the Granulator that we built to granulate old tires, in the plastic bottle recycling process...

The patent is expired...

image.png

Hmmm...wondering why that didn't take off...didn't do a your marketing research?...Could've tried to compete with

image.png

?

[Frederick_Law]

They're using corn milling Granulator to recycle metal.
Rebuild and improved a few on last job.

[MJuric]

For disposing of polystyrene, just put it out in sunlight....Most of our plastics break down by themselves. We just need a better means of containing it and letting mother nature do what she does. The convoluted things we try usually have unintended consequences that we then have to deal with, too.

I'd bet if you ran the numbers for how long it took various plastics to break down, combine that with how thin of a layer you would need for it to get enough UV to break down, combined with how much plastic we actually use....we'd probably all be ankle deep in plastic :-)

[Roasted By John]

It's a long story -

https://www.inquirer.com/philly/news/20 ... _scam.html

This is the guy we got caught up in and we were hoping to have him help us raise money before we knew what he was about. We were just country bunkins that didn't have enough of money so he took over the patent by promising us the moon and a few stars..

I built the first Conceptual Working Unit out of Scrap Material and I designed the 3rd Unit which is pictured. Mr. Sensenig used the Project to extract millions from the Amish and Mennonite communities through out the US. He raised 26 mil after the PA State SEC gave him a cease and desist order, by coming up with an amazing story.

We spent a lot of time doing Market Research and Testing to prove the concept and we were successful, but were blocked in taking it further and taking it to market. I still have the initial summarized report that Phil and I had compiled, the Mike Glant name should not be on the patent, he had nothing to do with it, except that he worked for Mr. Sensenig, screwed, blued and tattooed..

The granulator that is pictured in the Patent was driven by a 200hp motor and made rubber granules at a high volume. The entire system took 10% of a conventional system and replaced at least 4 -6 piggy back granulators. Plus we could go at least 6 weeks of run time before the knives had to be re-sharpened, while on the conventional granulators it took 1 hour of run time per 1 hour of maintenance, so if the granulator would run 8 hours, it would take 8 hours to remove and sharpen the knives and install them again. A lot of Rubber Recycling Plants burned to the ground because of dull knives, since our unit didn't need re-sharpening for a long time it ran cooler...

It is the greatest story that never came to fruition. The granulator was only the middle chess pc is our overall scheme of things, we had the whole nine yards from collection to product..

If anyone has a few million sitting around waiting for investment, this would be a really good process to get going again, the patent has run out and it is worthless till it can be implemented within the whole picture..

[mattpeneguy]

For disposing of polystyrene, just put it out in sunlight....Most of our plastics break down by themselves. We just need a better means of containing it and letting mother nature do what she does. The convoluted things we try usually have unintended consequences that we then have to deal with, too.

I'd bet if you ran the numbers for how long it took various plastics to break down, combine that with how thin of a layer you would need for it to get enough UV to break down, combined with how much plastic we actually use....we'd probably all be ankle deep in plastic :-)

So, how about we create some solar powered UV light arrays to help?

[Roasted By John]

Because of the blade design we could granulate almost anything, I found a small pc of a 9/16" Impact Socket, wrenches and other hardened materials. The problem with standard granulators is the shape and cross section of the sharpened edge, there is no mass behind the blade, therefore as soon as you hit the hardened wire of a tire it would chip or indent, taking away then sharpness and creating a high heat wear issue. At the time 90% of Used Tire Recycling Facilities burnt to the ground within the first year, all because of dull granulator knives and no heat sensor. If I remember correctly the highest temperature reading on our granulator was around 125F.

It is by far the best way to cut material...

[MJuric]

For disposing of polystyrene, just put it out in sunlight....Most of our plastics break down by themselves. We just need a better means of containing it and letting mother nature do what she does. The convoluted things we try usually have unintended consequences that we then have to deal with, too.

I'd bet if you ran the numbers for how long it took various plastics to break down, combine that with how thin of a layer you would need for it to get enough UV to break down, combined with how much plastic we actually use....we'd probably all be ankle deep in plastic :-)

So, how about we create some solar powered UV light arrays to help?

Maybe I'm not making my point well. Plastics take varying time to break down in UV light. The numbers are all over the place because we haven't done a whole lot of testing on it. Some break down in days/weeks. Other break down in months/years or more. So let's say that on average, and for ease of calculations, it takes a year to break down plastic.

We produce 380 million tons of plastic a year. UV light penetrates a maximum of .05mm into plastic. Plastic has a density on average ~1g/CC. 380 million tons is 345 Billion Kg's. 1cc of plastic at .05mm would cover ~200 CM^2. You could cover 1sq KM with 50K of plastic. Any more than that and the plastic is not exposed to UV and doesn't break down. So in order to break down plastic using UV and natural light we would need ~6.9million square KM of land with a .05mm sheet over it. Essential the stats if Rhode Island and Delaware would end up have an eternal .05mm plastic cover over them....assuming I did my maths right.

Now I suppose we could send half of it over to the Sahara desert, nothing happening there anyway and it's hot too.

[mattpeneguy]

Oh jeez....@matt was right to implement the purple for sarcasm, or a tag (I need to use it)...UV lights powered by the sun was a joke. You MAY be able to get more UV light that way, but even if you could, it would only be marginally better, definitely not enough to justify the cost of all the equipment, or dealing with it, upkeep, etc...
I don't guess we've interacted enough for you to just automatically go with "that's Matt, he's being sarcastic" yet....If you're scratching your head about something I post, I'm being sarcastic...unless it's something SW related that I'm not understanding.

Regarding the rest of what you posted, I'll take your word on the math. Yes, it definitely does take time and real estate, but sunlight is free...And I'm wondering if you couldn't set up some type of tiller that'd rotate the plastic? That's kind of the route I was thinking. But, there are apparently types of bacteria that may be able to break it down. So, maybe just burying it would work?