A close look at supercritical carbon dioxide CO2

[@TheKingofRandom]

This is awesome

[@frogz]

i wonder what seeing this video produced....

[@realreseller3102]

Its crazy that im the second like to a comment from 7 years ago

[@magichobo]

Rip Grant

[@deathrobloxian]

Wow never expected to stumble upon this comment.

[@N.M.E.]

F

[@TheCammerhammer]

This is an old video, but I still feel compelled to compliment you on practicing both safe science and overengineering of the design. I've seen too many instances where poorly-designed equipment failed catastrophically on the first try and the person was standing right next to the equipment. It makes me happy to see that you tested your pressure chamber at a safe distance, watching remotely.

[@kreynolds1123]

It was a really good job. I was wondering if he would use cement blocks to surround it, just in case.

[@rojaarkezor7185]

"poorly-designed equipment failed catastrophically" makes for better KZbin videos... If you want more views, just sayin.. lol

[@yzScott]

@@rojaarkezor7185 That is ElectroBOOM's bag.

[@SpadeNya]

"This is an old video..."

[@vaedkamat484]

@@SpadeNya lol

[@jaceshigh1]

A possible solution to your O-ring problem would be to loosen your gauge off so that it bleeds off CO2 gas until you have it all together and then tighten gauge up last.

[@pieterbezuidenhout2741]

My thinking as well but also cooling off the aluminium section before closing it up.

[@ynotwebb1408]

Good idea. Let it bleed . Or c clamp , then tighten bolts.

[@paulbiggs90]

@@ynotwebb1408 Don't you want the have high pressure inside though, as Co2 has to be above 75 psi to be a liquid? If you let the pressure out aren't you just letting out Co2 which is the equivalent of putting less in?

[@andyman8630]

cryo-freeze the entire apparatus, leave the gauge ever so slightly loose, fit a solid piece of dry ice which fits perfectly, g-clamp it and bolt it down! those few seconds of CO2 venting will expel the remaining air

[@skadi7654]

@@paulbiggs90 need to be fast.... it let the gas leak a bit to make the sealing more perfect

[@jkobain]

Hi! Thank you for creating this chamber and this video, and also for helping BlueNile with his project. You're awesome!

[@complexobjects]

Beautiful design and such an amazing demonstration of phase transitions. Its awesome that it's stable and safe to handel because that type of behavior is so rare to witness. I hope to see this in real life some day!

[@95TurboSol]

I would buy one of these

[@sang1025com]

me too

[@nozumihishimatchi1880]

Its practically a bomb though

[@turbo2ltr]

@@nozumihishimatchi1880 no more so than a CO2 welding tank... Except this one has a lot less CO2.

[@mikedavis7065]

@@nozumihishimatchi1880 nah I've worked with enough pressure vessels. The failure mode will be deformed plastic, oring failure and leaking CO2. You might get a freezer burn at worst, but explosion is not likely.

[@shonaoneill5151]

@@nozumihishimatchi1880 not even close!

[@FungusyHam]

"how i built it and what i plan to do with it" ..sounds really ominous, like you're a chill supervillain

[@bretmaverick9117]

You can also extracted the the essential oils from cannabis with supercritical co2.

[@omenakookos]

I like bananas

[@97skinnyboyswag]

"Essential oils" ;)

[@kleavenae]

Actually this is the only way to make THC e-liquid for e-cigarettes. So if you can do it, you could get rich

[@bretmaverick9117]

its not the only way. its just a common way. an even more common way is to isolate the THC fraction by molecular distillation with a shortpath distillation apparatus. 95%-99.9% thc is the same consistency as winterized co2 oil. a lot of people distill co2 oil to isolate the thc fraction. bho, pho, and ethanol extracted oil are commonly used also. the distilled thc fraction is 100% solventfree. The most well known brand of this is called "clear concentrate". The easiest way to make Eliquid is to mix bho with a thinning agent like PEG, PG, VG or naturally derived terpenes. Most co2 oil pens are co2 oil diluted with PEG. Open vape is the most well known and its half winterized co2 oil and half PEG.

[@bretmaverick9117]

I have been since 2009. ive been making it since 2010. its vaporized, not smoked. Meaning the oils are applied to a heated surface that they boil on and the vapor is inhaled. Im not sure what youre dabbing that would burn your lungs. Yes, i am after the essential oils. The oils in the resin glands are what gives cannabis its effect, smell and flavor.

[@sixpooI]

my wife is also supercritical, and she can also be used for drycleaning, but i dont think she would fit in this thing. suggestions?

[@ricktruman1416]

sixpooI were going to need a bigger boat.

[@resistortoresist5607]

what is the highest temperature ur superwife can carry out?

[@askhowiknow5527]

sixpool Here’s a suggestion: try brushing your teeth

[@ChiTownTino]

My wife can’t be used for anything....any suggestions?

[@SpudLab]

idk go to codys lab he has a pressure chamber for her

[@allenro1]

I would like to see something floating on the liquid co2 at the time it changes...😕

[@electric_photon4660]

I would guess it would stay suspended or sink to the bottom

[@pedrop1985]

Great video! Consider installing a safety relief valve on it, just in case you do place more CO2 than you should.

[@Plexiate]

I would really like to buy one of these.

[@Citizen-of-theworld]

Just don’t tell the delivery company you are shipping a home-made plastic cylinder under extremely high pressure! :-P

[@DrEnzyme]

That is the coolest looking thing I have seen.

[@AppliedScience]

The pressure in the chamber is over 1000 psia, as shown by the gauge in the video.

[@RadicalCaveman]

Extract the caffeine, eat it, then use the resulting energy boost to do more experiments.

[@rogueanuerz]

you would be died afterthat

[@pseudomemes5267]

or THC

[@ucid5363]

or psilicin 😌

[@ryans3074]

Sounds like the beginning of a vicious circle

[@AppliedScience]

Good question. As long as the CO2 is above the critical temperature and pressure, it is by definition a supercritical fluid.This implies that the chamber contain a certain amount of liquid before heating or else there will not be enough mass to raise the pressure high enough to reach criticality upon heating. If the chamber starts with only 5% liquid, no amount of heating will create a supercritical fluid. It needs to be *appx* 50% liquid to create enough pressure on heating to pass criticality.

[@YPOC]

The o-ring is not supposed to be pressed radially, the groove should be wide enough to allow the o-ring to expand when compressed into it's groove.

[@kaleu66]

Hey Ben, thank you for helping Nile with the pressure chamber. You are awesome!

[@ZeroMass]

Perhaps a small needle valve which could stand the pressure used as a temporary relief during assembly?

[@EwePoop]

Certainly! Adding a T fitting at the gauge will allow a needle or ball valve to be connected. Small high-pressure stainless steel ball valves are not terribly expensive. This also would make it possible to fill from a CO2 storage tank.

[@crocodile2006]

What did you do this weekend? Oh I mowed the grass and emptied the trash. What about you? Oh, I built a super critical CO2 Canister

[@archangel20031]

How about a 3 way valve between the chamber and the gauge so you can vent it?

[@AppliedScience]

Drill: Cheap Harbor Freight drill press - check online for price. Lathe: search my channel for a full review. Check Grizzly online for current price.

[@danielstjean9458]

When you were machining the aluminium body on the lathe why dident you just machine the o ring grooves after the facing cuts? Then make your bolt circle on thr mill. Easy peasy

[@AppliedScience]

In some ways, it's easier on the CNC mill because I don't have to measure anything, and the part will come out very close to spec'd dimensions. It would probably take me longer to measure and cut it on the lathe, even though I agree that lathe-cutting the gland would leave a better finish.

[@Hansengineering]

@@AppliedScience You've gotta go watch This Old Tony for a bit!

[@sisimig]

I found this video when I was trying to find a visualization of how the atmosphere of Venus with 96.5% Carbon Dioxide, a surface temperature of 740 K (467 °C or 872 °F) and a surface pressure of 95 bars would look like, since it is expected in these conditions that the CO2 would exist in its supercritical state. I was impressed to observe the phase change when the liquid phase mixed with the gas phase to create a light impenetrable mist that looked (to me at least) as a very Venus atmosphere-like. I think that simulating Venus atmosphere is an excellent use for your fine construction!

[@lqr824]

I love this thing! You could have kept the O-ring in place by freezing the components down to -20C, then cooling further with dry ice. If you did the final assembly in an open-top styrofoam cooler, the dry ice used for cooling components and filling the resevoir would also displace the air, I think, giving you nothing but CO2 in there. There's also got to be some amount of CO2 (maybe you have to measure to the 1/10g or something?) that would let it reach the triple-point?

[@NickMoore]

You have balls of steel. That thing is both scary as hell but infinitely intriguing, I would love to make one as a coffee table conversation starter. Keep up the awesome work!

[@scuffieduffie]

Just put the meter in last. O ring problem solved.

[@nickr4923]

aye

[@houseofwonders1]

good luck getting the dry ice through that little hole

[@GRBtutorials]

Felix Q Or do everything in a freezer. The only problem, though, is that it would have to be at a very low temperature, so his hands would freeze, but well, it’s a minor inconvenience (I’m obviously joking)

[@apexmike849]

Venting is a good idea. Also, preassemble the device as much as you can and use a jig if necessary and use a driver to zip those nuts up to torque very quickly. Alternatively, assemble the whole thing in a bath of liquid CO2. [joke]

[@AVBsLichtspielhaus]

Hello, a few tipps: - o-ring grooves are easier to produce on a lathe. - you can turn your aluminum ring, screw one acrylic disc onto it. then clamp the aluminum disc in the cuck and turn the acrylic.same procedure for the second one. - if you screw in the barometer AFTER you mounted the discs together, your o-rings will fit perfect. the overpressure will be able to flow out while you are tightening the screws. but however: its an amazing effect, i didn't expect. thanks for the video.

[@illumiNOTme326]

The acrylic should not be placed directly in contact with the liquid Co2. You should use a thin glass barrier along that is cut just a hair smaller than the diameter of the acrylic opening. Purchase a large O ring that is on the thinner side as opposed to the thicker bulky ones. In an ideal conditions the O ring should fit in the small gap between the glass outer diameter and the acrylics. When you join both sides together the pieces should be designed to press against the large O ring causing it to compress within the small space between glass and Acrylic. You may want to look into using some sort of Burst disc rated at a PSI that would in theory be below the estimated rating for the acrylic. When handling Cryogenics it can be very unforgiving. A leak or a tiny rupture won't really do much. If the acrylic becomes brittle and fails over large surface area then it will basically be a bomb.

[@anatolesokol]

1. Use turning to cut the o-ring groove. 4:50 2. "No valve on that chamber" - there was one. the gauge on top. you could close the chamber before installing the gauge. 3. "installed that in a corner" - at 6:43 we can see that you could do that danger test outside instead...

[@Sarge92]

i would love one of those on my desk

[@EwePoop]

Nicely done. Your chamber is much more elegant in appearance than one I built about 10 years ago. A layer of transparent fluropolymer film on the inside of the window can help avoid solvent attack of the acrylic. I had used one inch polycarbonate for the window. Supercritical fluids are fun. :)

[@MrWorld-hc5rs]

psi to bar conversion on screen would be nice.

[@bengr71]

To preserve the integrity of the o-ring, you could try pre-cooling the aluminum ring in dry ice prior to attempting assembly. Leaving the pressure gauge loose and tightening it last could also work.

[@shodanxx]

But then won't the o-ring shrink and also become rigid so that it won't comply to the mating surfaces properly ? ala challenger disaster !

[@A1Skeptic]

shodanxx But in this case the O-ring isn't being compromised by a large volume of high pressure burning fuel.

[@shodanxx]

A1Skeptic You mean the flow of matter past in contact with the o-ring would abrade it but not the very high pressures in this container ?

[@A1Skeptic]

The Challenger disaster involved a solid fuel rocket booster O-ring failure leading to a burn through that torched the main tank while traveling several miles per second in a near vacuum. What part of that scenario matches the conditions of this experiment beyond them both having O-rings?

[@voltare2amstereo]

applied and cody's colab?

[@robmckennie4203]

cody's science? applied lab? copplied scab? apody's lience? applied cody science lab, nailed it.

[@joshuapatrick682]

It can also be used for heating pipes..he says as he wraps it around a very thin section of pipe…

[@FieroFats]

Laundry? I don't think you can get a load in there. But in all seriousness, I haul C02 for a living, and I need this vessel in my life. :)

[@allenro1]

😂 Beverly Hills Doll Apparel Dry Cleaning...hmmm🤔i feel like it could be a thing if someone wanted it to be a thing...lol🖒

[@JesusCruz-my3ob]

I semi calculate the tensil force those bolts were holding. And the numbers are very tight. Thanks that they manufacture them with a safety margin.

[@bpark10001]

You should have aluminum rings on the outsides of the plastic windows to support them all around at these pressures!

[@vietho251]

Your tool look very nice, this is the first time I see a real super critical state of CO2, beyond of what described on books, thanks for your very interesting experiment

[@EpzilonZ]

Is this dry water now?

[@texasdeeslinglead2401]

It appears to be confused and slightly moody water now . Very dry sense of humor though.

[@whatshappenedhere1784]

Dry ice literally means ice with no water content

[@whatshappenedhere1784]

@@justotalkalottashit8392 Read my comment again pls, ty

[@purplemutantas]

Super critical CO2 is also used for making extracts of kava kava. The kava paste sold by iamshaman is made this way. I am sure you could do other plant extracts as well.

[@geodeaholicm4889]

have you considered repeating this adding a quantity of water & algae to it to see if the algae wood survive & metabolize the carbon dioxide into a significant amount of oxygen ?

[@akkupackage]

plants need oxygen too...

[@the-_-2145]

Akkupack thatis true but there still is some oxigen in the chamber to start with, you fill the chamber with water dryice and the remaining space is filled with air. After the alges start growing they will produce more oxigen then they consume with simple fotosynthetis: 6 CO2 + 6 H2O -> C6H12O6 + 6 O2

[@kreynolds1123]

My guess is the CO2 would act as a solvent that would kill algae.

[@onetrickhorse]

@@kreynolds1123 100% correct. The CO2 would dry the algae out within seconds, killing it rapidly.

[@DunkelStern]

to make it more easy to close it, you can try first cool down all your acrylic and then put dry ice inside, this will give you more time to close it

[@JustinHallPlus]

Could this be used to create a non-mechanical lens? I realize the applications would be limited (you can't control the temperature well enough for small applications). It seems like if the density changes with temperature, an adjustable lens with no moving parts could be formed by creating an enclosure with a gas reservoir, and a convex portion containing the liquid and then simply changing the temperature would change the density and focus of the lens. Or maybe I'm an idiot.

[@AppliedScience]

+Justin Hall Actually, liquid lenses are a real product. I'm not sure about using liquid CO2, but most liquid lenses use a combination of oil and water and a technique called electrowetting. I have a couple videos on the topic, just search for liquid lens.

[@JustinHallPlus]

Thanks, that was enlightening!

[@amirecospb]

+Applied Science can you give for us the plan of construction for this chamber please?

[@21Wakeup]

actually I was thinking along the same lines. like using a phase change like that with a laser passed through and measure the wavelength change as the phases change.

[@tellurium3754]

I can make a 3d model + DWGs within one week for 10$.

[@vincentandrew4717]

Yo, you have a truly amazing and unique channel, and for what it's worth, I'd like you to know that at least one person really appreciates these. Rock on.

[@Staremperor]

Great stuff. I'd just like to see metric units too. I (as well as most of the World) don't do PSI and °F, rather N and K. Of course, I converted the units, but scientific video should use SI units, don't you think?

[@Warhawk76]

Staremperor I am a scientist here in the US and I'm fine with either standard or metric. Conversions are so easy now it's not really an issue. I can see your point though.

[@onetrickhorse]

F is absurd for sure, it was invented using what I can only describe as arbitrary reference points like the freezing point of brine and the average human body temperature... it appeals only as a convenient measure for ambient atmospheric air temperature at sea level, with a general public-friendly range between -40 and perhaps 130 at the extremes. C is far better and logical, and K is of course essential, but less easily grasped by those without a background in science. PSI is also a bit awkward, I just tend to use the 14.5:1 bar approximation for quick calcs. Bar, although not an SI unit technically, is handy as it is a multiple of the SI unit Pa, but tends to reflect better the kinds of pressures used in most applications as 1 Pa is very small. I'm not quite sure what you meant by N, since it isn't a measure of pressure, rather 1 N/m^2 is equal to 1 Pa, which is what I assume you meant. But I do agree with you, SI units on a science-related video should be standard in my opinion.

[@pcorf]

6:45 to 6:53 is a good example of the liquid and gas phases merging as the temperature rises. The air on the surface of Venus is also a supercritical fluid because the pressure is 92 bars (460-480 degrees C or 860-900F) and its 96% co2 and the rest is mainly Nitrogen (also supercritical at 92 bars). Despite the supercritical phase on Venus, its still like a gas but the air also dissolves smoke, it floats. You cannot light a fire on Venus.

[@dany1398ify]

Is the liquid still there even though we can see it?.. and if so .. would i. "feel" it if i Shake this thing ( like when you feel that there is water inside a bottle when you shake it)

[@kreynolds1123]

In its super critical state CO2 takes on the properties of both a gas and liquid. Will it slosh like a bottle of water. Not really. A rough analog might be like shaking a bottle of soapy water. Slosh a little at first, then all the water is suds and doesnt feel the same. 3:07 the phase are completly blended together leaving no density variation to feel any sloshing.

[@onetrickhorse]

@@kreynolds1123 A nice analogy, I may steal it for future explanations!

[@kreynolds1123]

@@onetrickhorse its a pleasure to know i contributed in a way that is appreciated.

[@harriehausenman8623]

Just saw NileBlue's "Going supercritical." and realized I somehow missed this one from you. Glad you helped him :-) Many thanks!

[@alexpowers3697]

Not sure I can fit my suit in there for cleaning... hahahaha

[@aeriumsoft]

haha right

[@chiraldude]

You can buy CO2 in gas bottles with a head gas added (usually Helium). The bottle is filled about half way with CO2 then the head gas is added to raise the pressure well over 1200 psi. That way you can add CO2 as a liquid and fill the chamber completely with liquid. Of course you would need to buy hoses, valves, and fittings to hook it all together but having a super critical extractor setup could be useful.

[@davidmorris6439]

Couldn't you have installed the gauge after torquing the bolts to prevent the o-ring from deforming?

[@mrfnk]

Use a big c-clamp when you start to tighten the bolts to keep the o-ring from deforming.

[@AKU-zn3bl]

sir can you do these experiment with liquid nitrogen

[@snozzmcberry2366]

It would probably freeze the o-ring & render it too brittle to hold the seal. It would just shatter and release the pressure.

[@DominoSixO]

Build one in square or triangle shape and use "Peltiers" to heat it up or cool it down with a small regulator so you can just plug it in the wall or a power bank / usb. That would be cool/nice.

[@ybaggi]

sorry for the noobs question.but isn't the whole (heated) thing just all gaseous? How do you figuret it's supercritical? thanks

[@DaffyDaffyDaffy33322]

Yves Baggi The gas and the liquid are at the same (or very close to the same) density. Just as a helium balloon floats in air, the liquid floats in the gas and they mix and become essentially the same thing.

[@Nick_Tag]

That's not the right answer, because anything that you can read in a book should be measurable directly through an experiment (It is 35-36 Degrees C for CO2 I Believe). This is the answer: If you look at a P-T phase diagram the Critical point is basically where there is no distinction between Gas and Liquid, it is both. As in the structure of the arranged molecules are the same. To show that it is the critical point you can perform tiny changes in the environment around the point to reduce your uncertainty and show that it is the Critical Point i.e. T+ΔT, P=Const, then P + ΔP, T+ΔT, then P-ΔP, T = Const, then finally P=Const, T-ΔT. Keep doing that with smaller and smaller ΔT, ΔP and while ensuring the Mass / Volume are still const, to narrow down the exact the Super Critical point.

[@arturfilc9726]

Carbon dioxide supercritical state parameters are 87.98 °F (31.1 °C) and 1071 psi (7.39 MPa). At 700 psi liquid gas when heated from liquid state turns into gas state.

[@realcygnus]

this is cool as all hell ! ....btw... from the simple way you filled it...theres prob just as much N & O2 in there as CO2 ....which surly effects the critical Lambda point/phase transition temps & pressures....& 2 valves would be ideal.....also I wonder how energetic the explosion would be if it failed ?

[@dougguest6454]

realcygnusHe spent a fair bit of time showing the deformation of the O-rings from escaping CO2 as he was torquing the bolts. That amount of CO2 should have been enough to purge any atmosphere out of the space.

[@pyrokaren]

Thank you for making the transition to supercritical visible. I first learned of this effect when filling a sodastream canister from a large CO2 tank used for MIG welding. I mistakenly thought that if I heated the large tank and cooled the small one that I would get a better transfer. I warmed the large tank in my car in the sun and when it was uncomfortably warm did the transfer, and noticed got worse results than when just using room temperature. I assume supercritical CO2 was created with a lower density than liquid.

[@tellurium3754]

How are you going to open it?

[@mrbenjiboy9527]

unscrew it

[@dan8t669]

good luck what that

[@theopatimano3]

cool it down in dry ice so the pressure gets down. then open the screws

[@dan8t669]

it‘ll most likely crack and blow up

[@Terkinstein]

You could have placed the chamber under a hydraulic press. Immediately after dropping the dry ice inside, put it together quickly and then as fast as possible, apply a great amount of force while you install the hardware and torque it.

[@STONEDay]

Green coffee beans. That's not what we use CO2 extraction for in Canada. lol

[@BruceNitroxpro]

STONEDay, OMG, you really SAID that? ROFLMAO

[@STONEDay]

@@BruceNitroxpro Truth. Check out this video I shot of a commercial scale C02 extraction plant for cannabis [only]. kzbin.info/www/bejne/pXzOhmWFo9Z0hJI

[@treatb09]

from the performance specs i found online. acrylic pmma should need to be about .12-.2" thick to tolerate 850 psi of pressure.

[@gnome_farmer]

thc extraction

[@rickmorenojr]

My understanding is that supercritical CO2 can be used in high efficiency turbine generators.

[@RonJohn63]

Your electricity bill must be outrageous...

[@KallePihlajasaari]

You could pre-chill the parts in your super chiller to below dry-ice temperature before assembly. There would be very little sublimation while assembling.

[@henningerhenningstone691]

Anyone else here from Cody's video on Supercritical CO2 in a Glass Tube? :D

[@aeiouy2887]

no but i

[@MrHeuvaladao]

No. I came from Periodic Table of Videos channel.

[@ThaOGBabyOfficial]

nope, never watched, i watch legit science

[@jort93z]

Cody is pretty "legit" lol. What is "non-legit" science anyway?

[@jort93z]

Lol, fair enough. I dont think cody is a scientologist though XD.

[@PACstove]

Also, freeze everything as much as possible while assembling. It may reduce that pressure build up. You can get plastics to machine better when frozen also and even do cool press fits with a hot and cold piece. My tips.

[@dog5333]

Молодец! Нам нравятся твои видео! Продолжай в том же духе, дорогой друг 8))

[@bpark10001]

You can use supercritical CO2 to extract alcohol from silica jell to make aerojel (without collapsing the jel).

[@StingrayOfficial]

This thing looks so dangerous!

[@rustblade5021]

+Stingray my buddies tried to make a supercritical co2 extractor for plant oils... it exploded and blew a hole though a cinderblock wall

[@StingrayOfficial]

+rust blade Haha wow. Also, plant oils huh? Sounds fun!

[@jonathanreynolds7886]

Danger is 10% material, 90% moron.

[@onetrickhorse]

@@rustblade5021 Pressure vessels in general can be so dangerous, but with supercritical fluids the danger is magnified because of the way it reacts to most types of seals and soft components. If your buddies try it in future, my advice is to use already tested and rated pressure vessels (such as industrial pressure cookers, they can be easily sourced cheaply), get the pipework welded where possible using pipes rated to a safety factor of 2 for the pressure they're aiming for), and if they must use seals, make sure they're made of Nylon or similar polymer material with a decent thickness flange on the connections. I've helped design a supercritical CO2 research rig, and the flanges we used were nearly two inches thick. I would also make sure they test it first using air so they know it's capable, air isn't quite so bad if the thing decides it's had enough. During testing, we deliberately attempted to cross the critical point using an expansion valve (it was a closed loop waste heat recovery system, a bit like a Brayton cycle), and I can't go into details, but lets just say some very scary things happened when crossing the critical point. I can see why most engineers tend to avoid it at all costs!

[@onetrickhorse]

@@jonathanreynolds7886 Absolutely spot on!

[@mikafoxx2717]

I know this is an old video, but as CO2 is used as a refridgerant i just want to mention that no matter how much is in the system, it'll be the same pressure at the same temperature due to the vapor pressure phase change balance.

[@TheKevinGames]

Who came here from Nile give a like xD

[@IngeniousOutdoors]

so inlamens terms, its so close to being both a gas and a liquid, that thats why any disruption like you moving it around is the reason its jostles loose into a gas and settles back into a liquid? idk -_-

[@scowell]

Hash oil!

[@anthonylepore2088]

+scowell underrated comment.

[@jayb8056]

Water vs Dry Ice: its because water has a much larger heat capacity and can therefore absorb a greater amount of energy per unit of mass of water vs co2. Loved the video by the way!

[@DANGJOS]

I definitely have a suggestion for you. They say that the density of supercritical CO2 is about 464 kg/m^3 (according to Wikipedia) but I've wondered what would happen if you forced a substance to have a higher density than that. What would happen. In other words, you stuff just a little more dry ice in there, such that the density of the CO2 would have to be significantly higher than 500 kg/m^3. Check the pressure first of course, I don't know if it would just blow up in order to reach that density.

[@finalio]

For EOR purposes we use CO2 at super-critical conditions and we get around 5-15% incremental oil recovery

[@MrSunrise1961]

Thank you! That is totally awesome! Should be required viewing for all mechanical engineering students.

[@jasonmann42]

Someone may have already mentioned this, but you define the critical point as a pressure dependent property. This is a commonly mistaken concept. The critical point is dependent upon temperature only. Above 31.1 °C, no matter how much compression you apply, liquid CO2 will not form, you simply form dense phase CO2. The critical pressure you quote corresponds to the pressure at the maximum of the two phase dome within the P-H diagram (Mollier diagram) and is only significant if you compress adiabatically at temperatures below the critical pressure. Great video nonetheless. Might want to change those O-rings to Kalrez though.

[@yellowmetalcyborg]

Aside from extracting caffeine, you could extract essential oils from flowers with a supercritical CO2 chamber to make perfumes.

[@qweqwe700]

It's also used for extracting essences and perfume compounds from plants.

[@slevinshafel9395]

7:50 11 years later i have sugestion. Can you make close loop generator with Brayton principle? insteam of steam. Thank you. i am interested in presure and temp and state of CO2 in cold side versus hot side.

[@lorez201]

I noticed that, too. It looks even less viscous than water. Probably because carbon dioxide molecules are non-polar and don't form hydrogen bonds between one another, or any other type of intermolecular bonds, for that matter.

[@abmbarry]

Excellent experiment! ... Possible solution to the rapid pressure increase during closure is mount the chamber into an arbor press with a corresponding plate fitted to it. Rack the press down quickly to limit the "O" ring creep? I expect that you would have thought of many similar solutions? ...... I like this type of work, ..... always interesting. .....

[@chancedizzled]

Coolest video ever exposing what Supercritical is!!

[@firstnamesecondname5341]

I want this as a desk ointment, it will freak the heck out of anyone whom pops in and asks stupid questions 😁 Great video 👍👍👍👍👍

[@AppliedScience]

Good points. In this case, the supercritical CO2 made life especially bad for the buna-n, but the gland could have been better to begin with.

[@AflacMan13]

Apparently super critical CO2 at high enough temperatures is used for completely dissolving plant matter so as to be able to distill said plant matter and then filter it and get essential oils. This is also apparently THE best method for getting out THE most oils from said plant matter. :-)

[@AdorjanVas]

I don't know how many times have you heard, but this is awesome! 🤓

[@grimwulff]

Easily... relieve pressure on some bolts and slowly release pressure... at room temp, it won't do anything besides turn to cold vapor or go through the slight separation between the window and the body. It might freeze the two, but that is all.

[@icekk007]

To make the setup safer, I would add a Tee connection off the pressure gauge and add a pressure relief valve rated to your designed pressure.

[@carnivalwrestler]

You can extract essential oils from plants with this. Can be used for different purposes (I think perfumes, etc.), but be careful: I read that a woman had put just four drops of essential cinnamon oil in her bath, and she went to the ER with 2nd degree chemical burns. Essential oils can be dangerous.

[@Macmillium]

Like your meter, BK test bench 390, have one that unfortunately does not works anymore due to what I believe is a voltage regulator that went bad but can not find a replacement part. You are a great teacher, thanks for the video.

[@DmitryKiktenko]

You can screw out pressure gauge to make it leak pressure while your ohring is crushing. Then you can screw gauge to stop leaking. Very nice work anyway! It looks so nice and simple, i want to make the same one! ) Thanks for this video!

[@flailios]

To get the maximum dry ice in there, can you use a hole saw and cut a round shape? It may take some playing around with, but if the load is shaped ahead of time you could get a lot more inside. Also, perhaps a jig is required to hold the lid down while you fasten the bolts.

[@marty7922]

Put the chamber in dry ice before putting dry ice in it. Maybe this will prevent PSI buildup & not distort the O-rings. Just don't freeze the O-rings.

[@petersmythe6462]

I just realized.. 5.1 atmospheres is at least marginally within the capabilities of a soda bottle to survive. So as long as it's very cold, you could probably hold liquid CO2 in a soda bottle. It needs to be probably below -40 C or it would definitely burst, and below -50 C or it would probably eventually burst.