I did this experiment long ago but did not recorded. Yes, styrene yield is very high, and I can tell you the side products including black tar are not waste at all but other useful chemicals.
I bought a house and discovered the previous owner had basically never thrown away any of his packaging for any items he bought, and just left them in the crawlspace. It would have taken forever to throw it away, so similar to what you did, I melted it all down with acetone. It was amazing how the mountain of foam -- probably a cube 5'x5'x5' -- reduced down to a block of styrene that was probably 35 lbs, and a cube that was probably 1'x1x'1'.
it is truly insane how much it shrinks. Shrinks even more if you put it under vacuum, I didn't do that for this vid and you probably noticed the hard block of plastic I had was full of holes
The previous owner probably had done that for insulation, but it's not a real good idea for something as flammable as styrofoam to be used as insulation under a house.
Styrene itself is also not the healthiest substance. Among other things, it is suspected of being able to permanently damage auditory nerves. Peroxide favors the polymerization of styrene, but styrene itself, as an unsaturated hydrocarbon, can possibly form peroxides, which must be taken into account when heating styrene that has been stored for a long time. Benzene can also be formed during the thermal decomposition of polystyrene. All the more reason to conduct the experiment outside or under a fume hood and to limit the quantities. So far I have only carried out the synthesis in test tube format - also because I have not always succeeded in dissolving the residues from the vessels even with acetone. Please only do this with glasses that you are willing to sacrifice! Thanks for the appreciative words in the credits. I always enjoy watching! Edit: Great performance of this video - congratulations!
@@SciGuy700 I did this as well multiple Times and I recommend using a Steel can or some random steel container with some teflon tape to addapt to the glassware, also if your hotplate can't reach such a temperature using a steel can allows the use of fire or a bunsen burner
@@7hunderstorm242 Yes, and it's all the more annoying to have polymerized styrene inside the condenser. If you do it just small scale using two test tubes, an angle pipe and a old pierced rubber stopper, then a failure wouldn't be a big issue.
Overall - 8/10 for content. Background music is a tad loud, but I have old man hearing. Delivery is a tad dry, but you haven't been afflicted by that dreaded RU-vid tutorial speaking cadence and upspeak which is fantastic. You earned a sub from me. Well done.
Thank you! I will say I will probably begin to phase out music from my videos entirely soon.. I just think that they less and less fit my videos as I progress my "style". And yeah It is weird talking to a camera.. When I try to put enthusiasm in my voice it comes off horribly fake-sounding and weird to me so for now I'm a bit monotone but I'm working on it haha. Thanks for the sub and the feedback!
I love the idea behind this video. I knew ab styrofoam dissolving in acetone but I had never considered using that to create some useful product. I feel like this idea has a lot of potential for recycling styrofoam and I’d love to see more people do research on this.
Very nice video!! If anyone doing this is concerned about the toxic waste gases produced, an acidic KMnO4 solution could probably be used to scrub and oxidize them to benzoic acid. (It cannot oxidize benzene though.) I have heard that by controlling the temperature, you can selectively decompose polystyrene to ethylene and toluene instead of mainly styrene (but it will be quite a slow process since the temperature is lower than what you did here). By the way, can you please do more videos like this where you recover useful products from waste plastic? I would love to see a thermal depolymerization of polyethylene/polypropylene to produce alkanes!
I know perhaps this not practical but can you possibly oxidize the organic tar and byproducts into just CO2 using a piranha solution? Would it also produce some byproducts or is it strong enough to fully decompose the organic compounds?
Given that there is NO chlorine in polystyrene (and thus no dioxin risk), wouldn't incineration be at least as eco-friendly as letting all that acetone waft into the air?
@@Michael2137. In theory yes, but as the piranha gets diluted from the water produced by the oxidation its oxidizing power decreases, which may allow some stuff like benzene to escape off untouched. Even if piranha can oxidize everything, it will take a LOT of piranha that makes it impractical.
@@bcubed72 maybe.. Its all bad but I would think the inceneration byprducts (BTEX mostly) would likely be worse. Ideal would be a way to recapture the acetone, or do this in a chamber large enough to just toss whole chunks of styrofoam
In the second distillation you performed, it looked like your thermometer was a bit too low. It should be about 2 cm below the arm on the distillation head in order to get accurate temperature readings. Regardless, cool video, and there’s plenty of chemistry that can be done with styrene.
Instead of thermal cracking, there are actually several alternatives that could work at scale too but are definitely more expensive. 1.) Dissolve styrene in nitrobenzene, add it drop-wise to a solution of excess potassium permanganate in nitrobenzene at 70C. This will turn the polystyrene into potassium benzoate and CO2 with some potassium formate also present. This reaction is very clean and doesn’t make a mess of tar. 2.) If benzoic acid isn’t desired, again, there are other options. Dissolve polystyrene in benzene, add a dilute solution of sulfuric acid in water and illuminate it with blue light while bubbling oxygen through it. This will result in a cumene-like reaction in which the phenyl groups on the polystyrene chain get turned into phenols and the chain is left with many many ketone groups. This remaining ketone chain will get split into smaller chains until you end up with a mixture of mainly acetone, acetylacetone, diacetylacetone, acetoacetylacetone and diacetoacetylacetone. 3.) Similarly to the previous process, if plain chlorine is used instead of oxygen (without light, acid or water) it effortlessly converts the benzylic hydrogen to a chloride. The chloride when treated with a strong base (sodium hydroxide) in water turns into a poly-alcohol that when heated in the base bath for a long time breaks down into acetophenone.
Wait... Polystyrene can be turned into benzoic acid without the need of a depolymerization? Is it possible to dissolve it in acetone and add potassium permanganate to the mixture to form potassium benzoate right away?
I have used the primary mix of Acetone and styrofoam as an electrical insulator and glue for electronic components. But I have never tried to distill the dried product.
I would suggest buying an ozone generator and try an ozonolysis reaction to convert styrene into formaldeide and benzaldehyde I would like to try it one day myself But i figured out that the science and the fact that you can get something that smells like almond could be interesting
Why not start distilling the acetone-polystyrene mix right way, without prior evaporation of the acetone? Not only do you eliminate the 2nd smashing step, but you recover the acetone rather than put it in the atmosphere.
In retrospect that might work perfectly fine tbh. Only issue I could think of is you might end up with such a huge amount of acetone you might have to do a fractional distillation.. Then again the boiling point is so much lower you might not need to
It appears you've been blessed by the algorithm. Well made video, immediately subscribed. I'm also really curious as to what you have planned for that fresh styrene.
So rad! I loved all the research you did on styrofoam. I need to catch up on your videos. The chemistry you do is really fun. Especially with all the fact did bits along the way. Thanks!
@Apoptosis If you want you can even go a step further and turn the styrene into benzoic acid by reacting it with a basic solution of potassium permanganate.
Hey, just wanted to say that I love your videos! They are super satisfying to binge whenever I'm in a chemistry mood! If I may make a request, could you possibly do a video on how you clean your glassware and such? It's something I don't see a whole lot of, and it would help me a lot.
Cool process and great explanations! I think your 80 °C fraction product could be mostly benzene (which would be a novel way of getting benzene as a home chemist)
@@integral_chemistry Could you borrow from the transalkylation industry? You have plenty of sacrificial aromatic rings to transalkylate the "polyethylene" backbone onto - and easy access to styrene if you don't think a knotted up cross-linked polystyrene would be a good alkyl acceptor.
Styrene is made from benzene (which is a major hazard for the workers in these plants (because it causes testicular cancer)). (I did some engineering work on one - which also manufactured Glyphosate herbicide - same feedstock). Styrofoam is foamed with butane or propane dissolved in the polystyrene pellets under pressure. An overpressure failure in a polystyrene foam production reactor is “spectacular” (and not something you want to be within a kilometre of).
I've been meaning to do a vid on that for ages.. tldr for this type of organic waste I just collect it and turn it over to the state. inorganic waste I handle myself
I was told that, back in the 80s, one of the big Japanese conglomerates worked out how to dissolve the foam into citrus oil, then do fractional distillation to recover the oil, leaving reusable polystyrene. Allegedly was big in Japan but they didn't feel like exporting and the intellectual property issues kept anyone else from doing it.
that is such a bizarre combination but i can attest, this is gonna be a weird story. i work in a sculpture manufacturing shop where we make items for miniature golf parks. we have a small hill of polystyrene foam at all times, scrap. our shop was invaded by feral cats who loved to poop in piles of styrofoam dust and sawdust. it was horrible. management would not hear my urgent frustration as the smell got worse. one night my coworker counted the cats coming in for their nightly potty break, six at a time. I would not wait for management who was saying landlord was responsible and landlord saying mangers were responsible. i bought urine odor remover and 100% citrus oil, which i had read deters cats. on labor day while everyone was gone i suited up and dealt with the cat feces myself, wearing full protective gear. I plugged the holes in the sheetmetal walls with blocks of scrap foam, so the cats couldnt return. then i doused everything in the essential oil. i noticed where the citrus oil spattered on foam, large cavities appeared within seconds. only acetone does that, I thought. Wow, had no idea this was a viable technique to melt foam. probably safer than acetone, but citrus oil is not cheap.
@@MrJashuaDavies Assuming the distillation works, they are probably reclaiming the oil. (And there are other chemicals that'll do it, but most of them involve various health and fire hazards.)
That's a rewarding view count. Like I commented before, I don't think you'll have to sacrifice anything on your part to find a satisfying base on this platform. Hopefully your consistent effort is starting to be blessed by the algorithm
You actually use the acetone solution as craft glue or to make use of the plastic directly. Polystyrene is used for a lot of cheap plastic items, even without the foam.
This would be amazing if the output was something machinable. What a great way to both reduce the amount of waste going to landfills and also get very cheap machining stock, even if it's only for things like making jigs or using for test cuts. Is the material that you end up with after the acetone evaporates out fairly homogeneous, or is it full of bubbles, hard spots, etc?
When he's breaking the bulk polystyrene apart for boiling, it does look very porous. Probably pockets made by the evaporating acetone. If I was designing an industrial process to do that it'd probably be something like: 1. Blend Styrofoam and acetone. 2. Transfer the solution to a vessel where it's heated to the PS melting point and mild vacuum is pulled until no more acetone comes off. Condense and recycle the acetone. 3. Release vacuum and pipe the polystyrene melt directly into a pelletizer, or if that is too complicated, dump it to form sheets that can be crushed before feeding to the pelletizer. 4. Sell recycled PS directly or use for injection/extrusion purposes. Idk if it'd be profitable of course, but that's where I'd start. Maybe you could get away with directly melting the material, but that'd probably require much longer residence time in larger vats. So you'd have to compare the price of working with the acetone.
Yeah he is 100% correct, if you pull the acetone off under vacuum you end up with a crystal-clear product. The porous property actually seems to be (as far as I can tell) tiny air pockets that merged together during the drying. These can just be pulled out by a vacuum.
@@Ioun267 Sadly that sounds a little too complicated for me as a simple home machinist who likes to dabble in other hobbies :D It would have been really cool if it ended up as simple as "mix styrofoam with acetone" and wind up with a usable product straight away.
@Trainwreck1123 I melted a milk jug down to a solid block of plastic which I then used a piece of as a part of a tire tool that would ride on the tire rim while dismounting the tire to keep from scratching the rim. Suitably shaped I think that type of plastic might very well be machinable.
Awesome video, looking forward to what you decide to do with the styrene! Hope your channel blows up from this video, subbed as I always like new chemistry content showing up in my recommended
@1:32 - FWIW, it's advisable to keep Sharpie markers stored with the tip down for longest lasting performance. The dissolving Styrofoam was mesmerizing. I wonder if you could actually mill or lathe the polystyrene plastic like you would delrin.
Would it be a good idea to put the polystyrene/acetone mix into a distillation flask and distill off the acetone, collect it and then do the thermal decomp? Save some money and less acetone in the environment
These videos are awesome. Very informative and I will continue watching. You should make uranotypes with uranyl nitrate, or gold plate something with gold-panned gold!
Ooh I do like the gold idea! I haven't done much plating on here. I don't know where I could obtain uranyl nitrate but if I find a way that could be a cool project too!
Polystyrene is soluble in crude oil and can be directly recycled in a refinery. Oil refiners know this but, are they unwilling to use it as a feedstock voluntarily. There are other ways to reuse and recycle polystyrene foams but, the low density makes transport difficult. Compacting it first is entirely possible and it’s a social decision since it’s not profitable at current prices. A carbon tax might change that; carbon “offsets” are a scam.
If there was a way to extrude it into sheets, that would make a great recycle for us hobbyists who use the plastic in thousands of kits and kitbash projects
My Uncle once gave me a recipe for what he said was the strongest Varnish he'd ever seen. "Add 1,000 cubic inches of Styrofoam to one quart of Toluene."
Garbage dumps are compacted by trucks, bulldozers, etc, and the weight of more garbage, so I suspect that the "foam" volume ends up being pretty small. The styrene volume will probably last for eons.
likely candidate for the yellow/orange impurities are quinones from the oxidation of monomers and dimers, and less likely due to tiny amounts of fused aromatic species. I used to work up crude pyrene for fluoresce use and that easily went brown yellow overnight at rt if left in solution exposed to air
I know I'm pretty late at commenting but the first time I saw this I didn't know much chemistry, now I wanna start experimenting. Can you give me a list of tools you used in this process? Including beakers and stuff too
Now the question: for styrofoam it has been shown that some bacteria and insects can digest it - but what about solid styrene? If only styrofoam is broken down at a reasonable rate would that not means that solid styrene is more harmful for the environment in the long term?
@@integral_chemistry i think you wanted to reply to a different comment - one of those that mention that it kinda behaves similar to napalm du to its flammable liquid gooey sticky nature.
@@ABaumstumpf oh yeah you're right, my mistake lol. To respond to your question I would think the bacteria would probably consume the polystyrene at the same rate regardless, but the increased surface area of the expanded stuff would definitely help them break it down faster in general.. To be honest I'm not entirely sure what the best solution is long-term..
Wow, I am not qualified to take this experiment further but I would love to learn more about this process. I am in an industry that uses polystyrene foam as a building material and we generate a considerable amount of waste and I have appointed myself to find a repurpose or solution to either sell off or donate or chemically modify the chunks of foam. I have heard about blending polystyrene with acetone and we use acetone to clean spray equipment after using automotive clearcoats. simply reducing the EPS to sludge is not beneficial, though it saves space, evap of large quantities is not gonna be prudent in a workplace. i've learned EPS and acetone makes a great adhesive but i would end up with more toxic glue than i could ever use. I want to develop a way to blend EPS scrap with PE polyethylene into a polymer that has some of the rigidity of PS but with flexibility of PE. the PS alone is too brittle to use as a protective coating, and PE is too flimsy and soft. But together.... that could in the right ratio, provide an alternative to polyisocyanate resin coating, also known as polyurea, also known as truck bedliner. that material is applied to the sculptures as an outer hard coating and is what makes fragile polystyrene suitable as a sculpture material that experiences very rough treatment by caffeinated and sugar-addled kids at minigolf parks who will attack it with golf putters at a level just shy of outright vandalism. if anyone has insight into turning polystyrene scrap into a coating suitable for thermally-controlled plural component spray equipment I would be happy to compensate their efforts
Styrofoam is extruded polystyrene (XPS) made by DuPont but originally by Dow. All the foam you showed was expanded polystyrene (EPS). They’re both made of polystyrene but not the same. XPS is mainly used in insulation and EPS is used for just about everything else.
Styrofoam isn’t foamed with air - it’s foamed with butane or propane. The beads are foamed by applying heat to polystyrene beads saturated in propane under high pressure and temperature.
@@integral_chemistry Believe me - styrofoam burns horribly… You are also looking at gas pressure to foam the styrene at about 120C with a steam heated mould. PS softens at 100C (glass transition) but only fully melts at 210 to 249C. At ambient conditions the actual pressure in the bubbles is a pretty close match to a hard vacuum (which is why polystyrene foam is such a good thermal insulator).
Thank you! That's the biggest thing I'm trying to work on tbh. I'm fine lecturing or presenting to groups but it's so weird to me speaking into a lifeless microphone 😅 definitely improve with time
Inhibitor = hydroquinone or derivatives 1-2% w/w. Use it or polymerisation will occur, often with disastrous results. Renew the inhibitor at frequent intervals as it does degrade with time - 6 monthly or so.
this is an interesting way of disposing of / recycling styrofoam but what are the environmental effects of evaporating acetone into the atmosphere? Would it not be possible to re-condense the acetone so that can also be recycled?
So if you take normal craft polystyrene foam balls and heat them up in a craft oven to 275°F. Which I have done they shrink down to about 15% of the original size. Is styrene being released, I’ve tried to research the dangers of using this method in my crafting, but can’t really get any definitive answers. It’s either total toxic hazardous mess or no not a problem. Update question also in doing more research I see craft videos for kids shrinking Styrofoam. Also shrink plastic is also polystyrene which they put in the oven at 325°F But I can’t specifically find out at what temperature does the Styrofoam start releasing harmful substances. This is not for something I’m going to eat like heating up food in the microwave it’s just for crafting purposes.
275°F is well below even the melting point of polystyrene, so you'd basically just be softening it so it compresses. That will accelerate its natural decomposition (and release any toxic gasses it contains) but it wouldn't force-depolymerize it. Point is yeah as long as you have good ventilation that shouldn't be a problem at all!
@@integral_chemistry thank you for your input, that’s pretty much what I believe if you have any links to any legitimate factual data, please forward it to me. I’m trying to create a craft class, but I want to be prepared for the environmentalist extremist. It’s amazing when you go to websites to look stuff upand it takes you to an activist page and the misinformation they spew for scare tactics. It’s just amazing.
I don't know why I've never thought about this as a way to recycle my styrofoam! I have access to all the equipment/reagents/ppe necessary, plus I can try to convince my lab supervisor that it's a way to get some styrene for "free". (We use styrene somewhat regularly, but not much at all, so a few times our bottles have 'gone bad' and autopolymerized or something.)
It looks spongey bc of all the micro-bubbles that formed together into bigger bubbles as it dried. Best way to get a crystal-clear plastic you could put in a mould would be by putting it under a vacuum for a few minutes to suck the air out.
I don't have enough experience with 3D printers to really say, but if polystyrene is compatible with the 3D printers then yeah you could definitely extrude this stuff into wires and use it. May want to melt it under reduced pressure though first to get All the bubbles out first
yeah pretty much. The vast majority of the waste comes from styrofoam packaging and single-use plates/cups which there are plenty of alternatives for. However, styrofoam has plenty of industrial uses where it is more difficult to replace. It's also in a ton of appliances (Air conditioners, refridgerators, etc.) and I've got no problem with that.. Its more the single use crap that's a problem.
Hi and thank you so much for this video. After you dissolve the polystyrene in the acetone, howyou make sure the mix-mass you get will not stick to the metal..? I saw in another video it got stuck 🤷🏽♂️
I now remember that there's an "easy" method for this.... Not by breaking down, but styrene can be oxidised, just like toluene, to benzoic acid, using KMnO4/sulfuric acid.... The mixture is refluxed for a few hours, and the benzoic acid is crystallized from it... Then, benzoic acid is either converted to sodium benzoate, or used directly in a decarboxylation reaction with Ca(OH)2/NaOH, by dry distillation of the mixture, and benzene comes off as the main product... Imagine how useful it would be to get benzene from styrofoam, making nitrobenzene, aniline, chlorobenzene....
Percent yield for depolymerization is just product weight over SM weight. For weighing low density styrofoam, remember your buoyancy correction from analytical chem :P
Considering the price of acetone (reagent grade approx. $90/gal or $24/litre), dissolving PS waste in acetone is a rather expensive way of "limiting the amount of landfill space it would take". Probably solvent-grade acetone would be somewhat cheaper, but not that much I reckon, as even among solvents it ranks as pretty pricey. And at any rate that would make it "the cure worse than the disease". If you think that this would, or could make any impact (apart from the warm feeling of being a goody-goody chap) just place id (PS) in an oven set at 150-200°C (300-390°F), which is hot enough to make it colapse as softening point for PS starts at around 100°C/ 212°F (and it melts completely at ca 240°C/ 464°F - but you don't have to "melt it", all you need to do is to soften it to the point where cells would pop - the hotter, the faster it'll happen). Also, "dissolving styrofoam as the first step of de-polimerisation" is totally unnecessary, it only adds cost (acetone), and adds some unwanted reagent to the mix, as you can never remove (evaporate) 100% of the acetone used. (Also, it rises the risk of fire when you start heating that "PS cum leftover acetone" mixture - acetone will evaporate first.) Granted, ketones are not extremely reactive, but why add unnecessary step AND unneeded substance if you can just use heat to collapse the styrofoam cells? Me no understand... How to calculate yield? Geez, that's no brainer - it's the "most basic 101" of lab chemistry! Weight the styrofoam you start with (or better still, the "thermally collapsed" PS - cuz if you use acetone you'd need to calculate how much of it was left in collapsed PS), then weigh the product (distilled styrene - 54.19 grams, I reckon?), then divide the latter number by the former one, times 100%, and presto! (Or "voila!", if you want to sound sophisticated.) Frankly, I'm underwhelmed...
That's fair, I think maybe you just missed the point of the video. It's meant as a proof of concept rather than a perfected process. I buy acetone for $10/gallon where I live, I actually never considered it could be so expensive.. I think given the low cost of acetone and the high cost of the flack I'd catch trying to melt Styrofoam in our oven made it a good alternative for my situation 😅 As for percent yield yeah obviously I know HOW to calculate it (I generally do for my videos). I have an issue where I just kinda talk and post the first take rather than actually write a script.. in reality I just didn't get the initial weight of the bulk Styrofoam which would likely have been a better thing to say.. probably start actually writing scripts at a certain point.
@@integral_chemistry I might have missed "the point of the video" but I still think it's pointless to "prove the concept" that's been already proved beyond any doubts, but then again it's your channel and you can shoot as you please. And then there's this "comments section" when individuals like me can voice their opinion... Fair enough, I guess...? ;-) But then I also understand that, well, you gotta make SOME video every now and then good subjects don't grow on trees.... and then there's this thing called general populace and its lowest common denominator... Oh well, such is life, and let us not degrees unnecessarily and get back to the main issue instead, shall we? Good ;-) That price of acetone you are buying is very low indeed, so I guess its purity is "not that much", but it doesn't matter much in applications like this, and at any rate styrofoam can be dissolved by many other solvents - in fact, if memory serves me, it's soluble in styrene too. Still, I'd stick to the opinion that heating it is the better option, but yes, add the missus to the mix and things suddenly start becoming kinda... volatile, shall I say - or outright explosive. Speaking of which, it's "flak", as the original name, Fliegerabwehrkanone (aviator-defence gun) has no "c" in it. (I know, everyone does insert that "c" in flak, but it shouldn't be there; also, I'm a natural born knocker but then you probably realised that yourself already ;-) But then you can get some second hand old electric oven for few bucks, either at some garage sale or at Salvation Army store (or such). I mean, you can use acetone if it tickles your fancy and suits your budget better, but it's the omission of the other, more suitable for large scale true recycling process method that bugged me. I have no qualms about using acetone, but presenting it (in a sense) as "no-alternative available" method did rise my brows and made my keyboard itchy. Still, this miscommunication (of sort) highlights a rather common underlying issue, which is that people often don't realise that others can't see their thoughts, they can only hear and listen to their words (ladies do excel at this skill, I'd say...). Should you mention in the video "it can be also done using heat - you could place it in an oven at so many degrees for an hour or so, but I'm not going to do that because of the fear of invoking the wrath of the Goddess of the Kitchen, ...", or "I'm not going to calculate the yield cuz I forgot to weight that styrofoam before I started" (or "I should calculate the yield now but somehow I just don't feel like doing so so take my word for it that this process is pretty efficient") I wouldn't bat an eyelid - "fine, who am I to tell this guy what to do and what do not" - but when I see a clearly seasoned chemist saying something along the lines "gee, shoud'ev calculate it but dunno hawto" then it's instant "Whisky Tango Foxtrot" reaction on my side... Never mind, and to finish this little rambling of mine ("little", heh heh... ;-) I will add that packaging styrofoam can be upcycled by crushing it into small pieces and re-made into styrofoam sheets used for insulating buildings, but it seems no-one is interested in doing it - just as is the case with up-/recycling polystyrene in general. Cheers!
Hello, thank you for the video! You mentioned that you believe it's beneficial to use acetone to 'compress' styrofoam waste. Are you sure that the benefit of doing this outweighs the cost of releasing acetone vapours into the atmosphere? If so, how? :) Pierre
