Supercritical fluids

[@zman97211]

I would love to see a new upload of this with better quality, or a new periodic video with the prof and his apparatus.

[@MrVeryfrost]

agreed

[@RabanyMedo]

Better quality 8 years ago is bad quality rn lol.

[@PopeLando]

Little did the Professor know that after this video, he would now be on the path to worldwide fame and a knighthood!

[@drkdsz]

Would really love to see a much more clearer version of this process

[@SSJ9000Broly]

There are so many discussions about the toxicity of CO2 that people are forgetting the actual application of CO2 as a solvent. After it is used and the temperature and pressure return to normal the CO2 reverts to a gaseous state and leaves the material. That is why it would be totally non-toxic for use in the production of medicine for example.

[@Arycke]

It is used extensively in the extraction process involving marijuana b.

[@DANGJOS]

And even if traces were left behind, it still wouldn't do anything to you

[@RadicalCaveman]

@@DANGJOS Exactly, there would only be traces. It takes a large amount of CO2 to cause a human being any problems.

[@aparnavellala624]

CO2 is non-toxic,although it traps heat

[@holomurphy22]

Drinks with bubble are full of co2, co2 is in the air too. It's not toxic

[@patrickmcleod111]

Science aside, that's the coolest interview/recruitment strategy I've heard in a long time. Why would you want someone who appears to have no real interest or passion for the subject and the job?

[@nolansykinsley3734]

It would be cool to see an updated HD video revisiting this device, I would love to be able to see it clearer!

[@klausolekristiansen2960]

What a striking demonstration! I never understood what supercritical means until I saw this video (which was many years ago).

[@poulanker]

I first saw this demonstrated by my physics teacher at the University of Aalborg, Denmark in 1983 and I haven't seen it since - until now. Thank you for sharing. I remember how I was amazed and touched by the beauty of this tiny experiment. We didn't have cameras back, but some lenses and a light source prjected the image on a big screen, It was very fascinating to see these phaseshifts.

[@SamOperchuck]

THIS IS FREAKING AWESOME.

[@Nexus2Eden]

I suppose I should be working with the Professor - my immediate response was, "Wow! That is truly amazing!" lol More please.

[@mrbluenun]

Hi Sir Martyn, Not forgetting you Brady, thank you for your work together, and the upload of this really interesting video, great stuff! I realise this is just after you started your collaboration, for which I am so grateful, and is history now, but it is the first time I have seen this.

[@AMRnycmusic]

awesome demonstration. thank you!

[@Biotektan]

i had an interview today at professor Poliakoffs office! fortunately i allready knew this video ;) i totally freaked out when he showed me the machine

[@futureshock382]

This is actually a good representation of the ocean of chaos in the mythic traditions of most world cultures: There was first the Chaos of the Void and it was later seperated in two, to form the tranquility of the Seas and peace of the Sky

[@laserfloyd]

I could probably watch that all day long.

[@Sparrow420]

"just ignore the blurriness" Kinda hard to do in a cropped 240p video.

[@omegahunter9]

This is an absolutely fascinating effect. It would be even more interesting if we tried this as a plasma in this kind of environment, it's stuff like this that makes me want to be a chemist O_o

[@Sanngot]

I just learned about supercritical fluids today in chem class. But actually seeing how it looked is even more awesome!

[@ChrisBclips]

i was never interested in chemestry (more biology) till i watched these videos. i find it so facinating

[@gore14]

I'm fascinated! I wish I was over there to work with Professor Poliakoff. :(

[@nodariel]

Supercritical fluids are awesome. Nice demonstration!

[@carlosm-mcmxm]

I'm just studying this right now and I find this video very educational, besides the teacher (I imagine he's got a PhD or many) explains himself in a very understandable way. Thanks a lot!

[@klogdogger]

the pressure and temperature go below the Tc and Pc. This causes the liquid droplets to condense because there energy is low and the gas to bubble out because the molecules making the gas have a higher energy. This make a phase boundary quite rapidly and produces the storm ( the separation of the supercritical fluid into liquid and gas phases)

[@ChrisBclips]

this is absolutly FASCINATING!

[@GenericCoder]

That video is so cool thanks alot for this educational video. I find this really fascinating aswell.

[@ApolloWasReal]

@starked1 Supercritical fluids are already used in some spacecraft. The Apollo Service Module stored hydrogen and oxygen for its fuel cells in supercritical form. The tanks held much more than they could with compressed gases at room temperature but took less heat to vaporize than LH2 or LOX.

[@johnlebl]

The significance is from 3:43 to the end. Since you can use the supercritical fluid as a solvent instead of an inorganic solvent, it would be useful in medicine where an inorganic solvent introduced into an organism might be harmful, for example.

[@flozzalozza]

Very interesting! I was studying isothermal curves of a real gas, but I didn't understand them very much. I couldn't imagine a supercritical fluid and on my book there was written that it's impossible to see it. Thanks to my favourite chemist!

[@GOODBOY-vt1cf]

thank you so much

[@sporkafife]

I said wow when I saw that... in fact, I wanted to be there and ask some questions about it. I am more of a physicist but this just looks so cool!

[@jonnyreverb]

It would be neat to see the same thing, only with one of the windows at an angle, so you see the spectrum from refraction.

[@dcyanoura]

Since you have mentioned solid-liquid phase equilibrium of water (you talked about ice), we have to say that in this case we also observe an interesting behavior. This interesting behavior is that the P-T solid-liquid coexistence curve has a negative slope (whereas in other fluids is positive) and this has to do with the fact that the density of ice is lower than this of liquid water. Due to this fact, increasing the pressure drives the water into the higher density phase, which causes melting.

[@Direkin]

That's the same monitor I use :) Interesting effect too.

[@dondude69]

Fascinating!

[@Branhawk]

Oh man that blew my mind! 👍🏼👍🏼

[@stijn3113]

Very interesting demonstration, i like it

[@Melthornal]

What has amazed me ever since I first saw it is the water droplets that fall out of the air when an airplane breaks the sound barrier. It goes from air to water INSTANTLY. Its like alchemy or something.

[@volodyanarchist]

I'd definitely go "Wow!"

[@9Patroclus]

Hahaha!

[@jareddkearns]

You're hired!

[@TheUnPlayable]

Saw it a week ago and it's beautiful !

[@Slarti]

@DubIDubblix You said - "The surface tension disappears. I have no degree and was able to grasp it." - I just skimmed through the wiki on surface tension and am most impressed that you understand this area given the molecular and mathematical complexity of surface tension. It does not answer how when surface tension disappears that a liquid will flow up vertically though.I don't think you understand the slightest thing about this area which is why you have fobbed me off with visiting the wiki

[@ApolloWasReal]

@starked1 Oh, and the Apollo Lunar Module stored supercritical helium in its descent stage to pressurize its propellants. In the Service Module the supercritical O2 and H2 could become non-uniform or "stratified" in zero gravity so fans were added to stir them occasionally for more accurate quantity readings. On one flight, damaged electrical insulation on the fan in one O2 tank caught fire, resulting in the Apollo 13 emergency.

[@jaksn]

has this experiment been done in Space (in a 0 gravity environment) already? or are there any predictions on how the condensation process will occur?

[@jaksn]

i mean in the video you can see how the supercritical fluid liquidizes again at the bottom of the container, which one could expect in a gravitational environment. i would be interested, whether it will form one big sphere or many tiny ones, or just randomly/chaotically condensate in a 0g environment...I am not quite sure if you understand what i mean..

[@adampe9103]

I think when cooling, water should form a big drop (after some time) with gas around it.

[@ilikepi55]

Well, supposedly, the process of separation would instead show the liquid material not actually falling, but rather gathering from individual particles, into droplets, into tiny balls, and then, in a perfect environment, a single unified sphere of the liquid surrounded by the gas.

[@bozo5632]

In freefall I bet the water would stick to the wall of the container cuzza adhesion, and the vapor would be the the ball in the center.

[@Slarti]

@DubIDubblix Thank you so much for your explanation! Can you please now explain what surface tension is? Why when surface tension present a liquid behaves the way it does and why when it is not present the liquid behaves differently? "Seeing something happen" is a whole order of magnitude in difference to understanding and being able to explain why it happens!

[@social3ngin33rin]

Can we do an updated video on this using a higher quality camera? :)

[@guitar23man23]

Martyn is my scientific idol.

[@safibn1]

Does surface tension play a role in the "storm"? I did see more water stayed up on the sides of the container before "raining" down.

[@ForsakenForWhat]

There are so many discussions about the toxicity of CO2 that people are forgetting the actual application of CO2 as a solvent. After it is used and the temperature and pressure return to normal the CO2 reverts to a gaseous state and leaves the material. That is why it would be totally non-toxic for use in the production of medicine for example. copy pasted for reference

[@decent.mughal8466]

Wow 🤩… it’s so amazing to watch this

[@ib9rt]

@Defonthana Yes, providing it is stable and does not decompose at the critical temperature and pressure, every substance can be made supercritical. For instance, some of the very efficient power generation plants use supercritical steam.

[@edgajam]

Nice to meet you, Timmy McMouthfull.

[@roshanakmofidi]

awesome! i love him!

[@laroete]

i learned more from this video then a whole hour in school

[@baguazhang2]

There are a ton of other applications as well. Like I just mentioned in my mast post, you can run wastewater through a supercritical fluid to destroy the bad things and get clean water. Supercritical water forms an extremely, extremely harsh environment.

[@MarkShannonroad_videos]

That was cool!

[@ApolloWasReal]

I wonder which demonstration he saw 20 years ago. I saw it done with CO2 in the British Science Museum in London about 10 years ago, and I was also fascinated. I think he uses SF6 here because CO2's critical temp is only 31.1C and can be reached on a warm day. SF6 has a critical temp of 45.5C, well above room temperature, so his demo is guaranteed to work even on a warm day.

[@eboueboy1122]

its kind of cool how you can have the liquid and gaseous co2 under the same pressure... If I could ask, what is the pressure in the containing vessel professor..?

[@marekmokwinski44]

c) treatment of a supercritical reactor tube without flow - to work periodical - the disposal of the body (cremation supercritical water), disposal of medical waste. d) a dosing and bleed into the reactors.

[@Fish12002]

@Ducky1138 You appear to be unclear on the definition of fluid. In common speach they are often used interchangably but there is technically a difference. Simply put, a fluid can be any material which can flow, which includes gasses as well as liquids. The critical point is the point on a pressure/temperature graph at which the transition from two distinct phases (liquid and gas) to a single phase (as shown in the video) occurs. As this exists above that point it is called super-critical.

[@tom_something]

I know some people might be concerned because CO2 is a greenhouse gas, and I'd like to put those concerns to rest. There is no shortage of CO2 for experimentation. There is an abundance of CO2 from other chemical processes. This is a chemical compound that was going to go into the atmosphere anyway, but was captured on a brief layaway to accomplish some other tasks first. Whereas many of the organic solvents that are toxic and used in chemistry are deliberately manufactured. So if no one used CO2 for this purpose, we'd be making more of these toxic compounds, and at the end of the day, there would still be the same amount of CO2 being released into the atmosphere. Imagine finding a way to use toxic waste for a while before dumping it into the ocean, rather than dumping all of that toxic waste into the ocean directly AND also making some other more specific toxic waste for some other brief purpose. That would be bad. It's not a perfect analogy. Unlike toxic waste, CO2 is a necessary part of the ecosystem. But there's a balance we should be aware of, or nature herself will simply shrug humanity off to make room for some other organism to take over..

[@nokbient]

@danx033 Supercritical fluids are basically one state f matter that doesn't know what to be because it's under alot of pressure so the molecules can spread out

[@marekmokwinski44]

b) pyrolysis or combustion of hydrogen with oxygen plasma stream with an aqueous suspension of power supply 2) technologies, over-, sub and sub-critical - four patents: a) rendering supercritical reactor pipe-Field-flow-modified type II - mobile technology for continuous operation b) treatment of a supercritical reactor flow tube combined targeted - mobile technology for continuous operation

[@akashashen]

Carbon dioxide is totally non-poisonous. I love that line. I think he's one of the 16 Concerned Scientists.

[@marekmokwinski44]

These patent applications: P.403320 - The method of disposal of mixtures and suspensions of the hydrated 27.03.2013 P.403322 - Disposal of mixtures, suspensions and solutions in the states of: sub-, and supercritical 27.03.2013

[@tutentDotCom]

Very cool stuff!

[@starked1]

Professor Poliakoff - I think this would be an amazing apparatus to put on the ISS! What would be your thoughts of what might happen when the material is alternately heated and cooled without the effects of gravity?

[@marekmokwinski44]

P.403323 - The way of the pyrolysis 27.03.2013 P.403744 - Disposal Mobile mixtures, suspensions and solutions in the states of: sub-, and supercritical 29/04/2013 P.403784 - Mobile as periodic disposal of mixtures, suspensions and solutions, especially in the states of: sub-, sub-and supercritical 05/06/2013 P.403785 - Dosage and bleed flow, the pressure reactors 06/05/2013 I expect to have two numbers of applications.

[@dnas2]

Wow, very neat.

[@johnchj]

Now, this is cool.

[@yoduh99]

Carbon dioxide is not considered toxic but at high enough concentrations it can displace enough oxygen in the air where you would simply suffocate. Carbon monoxide however is toxic.

[@iambiggus]

I'm not interested in a degree, or a change of occupation, but I would seriously pay admission to come hang out with you guys while you work =).

[@pcorf]

45 degrees so its Sulfur Hexafluoride. SF6 only requires half the pressure of CO2.

[@CarpeMetus]

So awesome!

[@DougPoston]

Depends on your definition of a pollutant. It fits the common definition: "Pollution: introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem" But other groups only consider elements toxic to humans (such as Carbon Monoxide) to be pollutants. But all this detracts from the main issue, large amounts of man-made CO2 (mostly from burning coal, oil, etc.) is causing the planet to heat up at an accelerated rate.

[@raiccoon13]

Nearly 9 years from now, awesome.

[@keghnfeem1479]

If you put a tiny sealed drum inside and was spun like a car tire and it had a small hole one side and a axle on the other to spin it. Would a phase bounder form from hole to the spinning inside tangent edge be formed? A gas to super critical from the centrifugal force. The inside would have fin to help the gas get moving.

[@Flachzange1337]

@threejchapman The maximum pressure in this experiment is not higher than 75bar. I have build such an apparatus and it gets supercritical at 31°C.

[@khilorn]

Whats the difference between a super critical fluid and plasma. My chem teacher never taught me?

[@wnderer4365]

can you please upload a high quality version

[@SamuelSilva-t8m]

so, I don't think that a video from 13 years ago would be any better than this

[@SkyBlue222222]

Does this apply to the weather? The reason why there are storms.

[@DevilMaster]

@Fusurugi No. Plasma is ionized gas.

[@rinsedpie]

in laparoscopic surgery, u need to expand eg the abdominal cavity temporarily; you use CO2 there n plenty more other uses

[@itshelpa]

Marty, we gotta get back to the future!

[@omega7arts]

could you re-make this video in better quality? :)

[@killernat]

@wannabeers oh right i think he mentioned its SF6 at some point so yah the pressure would be decently low

[@jhyland87]

So i get this got you hooked, but WHY did it get you hooked? What about this was so fascinating to you?

[@Roddyoneeye]

Can lower temperature supercritical fluids be used as lubricants, or as a suspension matrix for industries ? It would appear that they have a greater measure of "slipperiness"

[@Ducky1138]

I would have expected this as part of a physics demonstration, we're seeing physical properties of phase-changes that are done and undone by physical means.. Was this experiment initially discovered performed by a physicist? Why is it called a Super-critical Fluid, rather than a Super-dense Gas? Does the Super-critical Fluid have more properties related to fluids than gases? Is CO2 condensed to make this since at room temperature it's a gas already?

[@DazIOM1140]

Is this what led to the Periodic Table of Videos?

[@bruceliu1657]

this might explain some weather effects!

[@Trifu22]

Can I use liquid butane or methane?

[@BubbaHoggit]

Thank you for calling me on that. But it doesn't explain the problem of infrared light carrying too little energy to greatly warm the climate.

[@paulflute]

would it be possible to colour the liquid to make the change visually clearer.?

[@DubIDubblix]

@jagara1 You misunderstand. I don't care if you understand it. I learned surface tension in high school and while the math is complex, I didn't have problems understanding it. Its not my problem that you don't get it.

[@TheSeaFour]

That was interesting.

[@Crystalh321]

the cameraman likes zooming in and out too much XD

[@rubikfan1]

what if you have a supercritical fluid container, but force more water/steam into it? until it reach a denity above that of the original water. can it be considerd a fluid again?

[@klogdogger]

They don't "almost meld" They do become one there is no phase boundary.... That is what happens above the critical point. Look on a phase diagram for Carbon dioxide sometime and you will see what I mean.

[@bigtrippy]

i am interested how many chemicals have this been dun with and have u ever tried mixing chemicals this way

[@captkirkconnell]

great qualification gage. "whats that?" It is an interest gage.

[@heavendissection]

But it's not really a closed vessel, isn't it? I mean, you have the phase boundary so you don't really have the liquid filling the whole volume of the container.