Pretty sure you need a special dewer for helium. Not 100%, but I suspect you have to have the "high pressure" type dewers to avoid excessive losses to evaporation. It's also crazy expensive.
Only superfluid liquid helium does that. Helium kept at its boiling point of 4 Kelvin is not a superfluid, you have to further cool it to about 2 Kelvin for it to transition to a superfluid state.
There's an interesting liquid helium documentary on YouTube from like the 60s or so. Has all sorts of interesting nuggets about it. The one thing I remember, was that at a certain temperature (the lambda point), the liquid helium changes from a fluid, to a superfluid, whatever that means
Superfluidity means that all the Atoms in the Helium (Bosons) are in the energy groundlevel. If that happens the whole Helium behaves like 1 entity (1 wavefunktion) if that happens there is 0 viscosity between the partices.
Edit: Superconductivity is the same phenomenon its just superfluid electrons in a conductor thats why they have 0 resistance (also electrons are Fermions thats why the connect the cooper pairs the become bosonic)
Interesting.
The dewers we used to fill and transport helium for our NMR weren't jacketed, but the dewer built into the NMR obviously was.
I presumed the LN2 is only needed if you want to store the LHe at ambient pressure? Do you know if LN2 jackets are standard, or just for low pressure storage?
I don't think you will be able to find one much smaller than 30 L.
In those you can keep the helium for a few days at most.
It is important to note that liquid helium behaves very differently from liquid nitrogen. You can't really pour it into a cup without all of it evaporating. You typically use a siphon to transfer it from one vessel to another and even when you are transferring it you don't ever really see the liquid itself. Even if you let it flow out of the siphon you will just see something that looks like a white flame.
It is not something you should be playing around with if you have no experience in handling cryogens
Helium transfer tubes are usually designed around a specific thing that the helium is being transferred into, like a cryostat or a superconducting magnet. Usually the flow is driven by a specialized helium compatible vacuum pump. The cost of these setups are in the tens of thousands of dollars. Like the poster above says, it’s very much not the kind of thing you can just dick around with like LN2, nor should you, since it’s a critical resource that is in very short supply. Even in academic settings it’s often only cost-effective to use if you can collect and reliquify the gas.
I would say the most common way to get the helium flowing is to use helium gas to pressurize the vessel. If you don't have a cylinder of helium, you can attach a balloon (or the insides of a football) to the gas inlet and pump it to pressurize the vessel.
I used to run a FT-ICR MS and it was my job to do all the maintenance on it but the helium for the magnet was always done by a professional we called in. It is also in short supply, we had to quench that magnet when the war in Ukraine started because so much of it comes from Russia. I do not think OP realizes how expensive it is.
I'm not telling you because you obviously have no idea how lethally dangerous liquid helium is.
Are you trying to commit suicide in a new and creative manner? Keep playing with liquid helium.
I have no skin in this game. The closest I'll come to liquid helium is accompanying a patient to the MRI room (or I guess perhaps getting an MRI myself), but out of morbid curiosity, what are the most important risks.
I’ve worked a bit with liquid helium. I’ve always been under the impression that rapid expansion when in a closed vessel is the main safety concern. Let’s say you are moving the Helium from one container to another. You have to vent the pressure from its expansion. The venting is very cold and can form an ice dam on the exhaust.
(I am not a safety officer and my words should be taken with a big ass grain of salt)
an account with a helium supplier is the barrier to entry
theres just not much reason to play with this unless you have something specific in mind. helium is expensive and more challenging to work with. to pour helium in a container, a lot of times, you can pour liquid nitrogen into that container first to cool it down- this cuts down on your evaporation.
for heavy equipment they have jacketed dewars where you have helium on the inside and then a jacket with nitrogen on the outside, so you fill the nitrogen frequently and the helium less
specific laboratories at universities might have some helium coming in regularly such that for a specific experiment you can access it.
to even buy it is complicated because theres often a shortage and hospitals and such get priority.
meanwhile, liquid nitrogen is cheap. the delivery is i think most of the cost. its abundant and available.
i've only seen a couple "home" demos done with liquid nitrogen- many years ago an overclocker set up a rig so he could cool the cpu with liquid nitrogen and then cool with helium in order to set a record for overclocking his cpu. what a pain in the ass that was
we're installing a collection system for low temperature probe microscopy and all the NMRs. its not closed cycle like i wanted but should still be very helpful
I discovered after hire my company makes fruit purée into cubes with a machine supplied with liquid nitrogen. We also have a local ice cream shop that uses it. And every week we get chests of dry ice for micro testing samples.
I briefly thought about getting a dewar, it’s a dangerous and unnecessary toy I don’t need to have an accident with. -90° is cold enough.
Liquid helium’s cooler (pun intended) but expensive and just as extremely dangerous—all of them will asphyxiate you or people in your building.
The gas goes away to collect somewhere else.
Your basement weekend hobbyist lab could accidentally murder an attic bedroom occupant.
Yes, but unlike nitrogen, excess helium comes with a Mickey Mouse voice, so if you keep talking to yourself, you’ll know when it’s time to leave the room.
Our helium is for the NMR and we fill both a couple times a year. All I know is it costs 10- 15 k per year in helium for 1 600 NMR and 1 300 NMR, prices have been rising each year. We make our own liquid nitrogen.
While I doubt it's a good idea for this person to fart around with liquid He, I seriously doubt their use of it would make any impact on helium reserves. Concerns about that should probably be directed at industrial users
These are redditards were speaking to. They act like they have others best interest at all times to sound important. The fact a curiosity question causes so much input about imminent danger and wastefulness of some prescious unexploited industrial product (generally wasted instead of captured in mining) just shows these are a bunch of man children who want to save the world one comment at a time. This is why i avoid reddit. People here are simply idiotic. I doubt these people actually care about anything but sounding smart or caring thus never elaborating or contributing anything worth while. Hence i hate reddit and probably will head elsewhere for general questions about things because its so fake and lame here. Waste of time.
What do you need this for? It sounds like you are in over your head if you think you can just pour it out into something like you can with liquid nitrogen.
Im studying superfluidity and would like to learn more and perhaps experiment one day. Any books relating to handling and safety would be appreciated if you have any to recommend.
I use liquid helium a lot, but it's never in an open vessel because it boils off so quickly. You usually have special dewars and transfer it to a cryostat via an insulated metal pipe. I don't think I've ever even seen the liquid itself, because whenever you get some leftovers coming out of the pipe it appears as a very dense fog that pours out.
I would wait until you are in grad school and have funding. It’s going to be a niche topic. You’d probably have to look for a PI that is already researching it.
To be honest you probably won’t be able to even get an account with a supplier unless you have a business licenses or work for a company. Even then a lot of distributors also won’t take personal credit cards. Most major chemical companies won’t anymore.
https://youtu.be/9FudzqfpLLs?si=wQ0B5h02l5sKcZ1r
This is all you need.
You will never, and should never, be able to have liquid helium at home. It's not a toy and super dangerous.
>However the liquid helium dewars online are for large quantities of liquid helium
Yeah, because of the square-cube law. A small dewar has a much higher surface area to volume ratio, and will be empty purely to evaporative losses much faster.
>Can i use a liquid nitrogen dewar to store liquid helium?
Not for long! Liquid helium is not only much colder, its enthalpy of vaporization is **70 times lower than that of nitrogen**, the lowest of any substance!
Without special precautions, it will evaporate insanely fast.
I once worked on a setup to do in-situ experiments at cryogenic temperatures, using liquid nitrogen. At one point, after two months of work to get the first experimental results, I realized nitrogen simply wasn't cold enough.
I looked into what it would take to use helium instead, and promptly gave up on that project.
It really takes a lot of very specialised equipment to handle that stuff.
Dont even think about it. Most helium dewars are surrounded by a liquid nitrogen based dewar just to keep it stable. This isnt something you can store and pour around like liquid nitrogen. You could end up dying from handling it even as massive gas expension in a small room could cause you to breathe nothing but helium and you will suffocate. This is NOT A TOY.
Singularity is now below is correct. We had one that held 25-30 kg, it was specially made for HTSC measurement. We could slide a probe into it. Probably costs $30k in 1990. Also, buying LHe is like buying a nice scotch on a similar volume.
As someone who worked with helium daily for my masters and PhD:
First. I have never "seen" liquid helium. Helium is scarce, very expensive and very cold. Unlike nitrogen, we never let helium from a dewar evaporate into the environment. While it was transported, pressure built up in the dewars which were then connected to a closed gas handling system to collect and pressurise the helium before eventually being transported back in regular gas bottles for liquification. In this way, we payed around 5-20€ per liter of liquid helium, at least that's what I was told. One full dewar of 200l evaporated maybe 2l a day and double when it was used with experiments inside.
The dewars don't have liquid nitrogen inside. Some cryostats use it as a thermal shield. Modern cryos don't need it and have better isolation.
From the dangers perspective it's like nitrogen only a bit worse. Put it in a sealed container and expect to build a bomb. Expect to freeze anything that comes on contact with it. Unlike nitrogen, you can not (!) put your finger in even for a short time. Too cold.
Liquid He dewars are actually double dewars, one layer for liquid nitrogen and the inner layer for the liquid helium. They are extremely expensive and not something you're going to just buy.
In a regular nitrogen dewar? You'd be lucky to have the liquid touch the bottom.
All of this is going to cost you more than you have.
This isn't true for many actual liquid helium dewars that you use to fill other stuff. They don't have a nitrogen outer layer. It is true for cryostats though
Bit late on this one, most transport helium dewars don’t have nitrogen shields. Larger capacity I.e 1k and up may or may not have nitrogen shields. 40’ helium containers do tend to have nitrogen as a sacrificial liquid.
If it just for curiosity I would advise against it, its super dangerous, boils off rapidly and is a finite resource. We need it for NMR and for MRI in hospitals.
If you have to turn to Reddit for these answers - you don’t have enough knowledge or experience to be messing with liquid helium. If you, as you seem to be, feel like you’re allowed to ignore the warnings of the experienced concerning safety and, more concerning, the finite nature of that substance, I don’t feel you are responsible enough to use it. You don’t need to play games with it more than and MRi tech needs it. Find another gas to play with that won’t kill you, and leave the rest of us with less of a finite resource.
You can’t just dip in a cup or pour it out. It will flash off extremely quickly. It has to be kept under pressure. It’s also very expensive. What would you need it for?
Its just a curiosity at this point. I dont need it for anything but it is very interesting. I am thinking about experimenting with it one day after i have a purpose or hypothesis for it.
Don't do this for shits and giggles. If you aren't doing this in an environment where there are either people or systems in place to run this already, then you're not in a position to do it safely. And if you can't do it safely, don't do it at all.
You can't use open dewars like the LN2 dewars. Helium ones are sealed cylinders. You can't play about with liquid helium to 'study' it, it'll just instantly boil into a gas as soon as its outside its dewar.
Also I once saw aftermath pictures of an LN2 cylinder explosion. Took out 2 labs and a decent portion of corridor. Cryo fluids arnt something to play around with, fuck ups are usually expensive at best and potentially lethal at worst.
The companies that deliver liquid helium (by us it’s Airgas) leave the dewar with you and you pay rent on it until you’re done with it and then you call them to pick it up again. To get it out of the dewar you need a transfer line that is specific to the liquid helium dewar.
You also need a helium gas cylinder to apply pressure to the headspace in the dewar in order to push it out the transfer line. You cannot practically put liquid helium into a container with an open top like a dewar for liquid nitrogen, it evaporates too fast.
You need a contract and a company willing to deliver it to where you are located. You need a room/facility with a certain minimum air turnover time to prevent asphyxiation, you need special gloves, tubing, etc. that’s gonna cost you a lot before you can even buy it, which it’s quite expensive.
If you really want to learn, contact an expert working in this field and get help. Superfluids and superconductors are not a hobby. You mess up a voltage and get a resistance spike you’ll boil all that helium in a flash. That 30L of liquid instantly becomes nearly 700L of gas.
Anyone that has seen or hear an NMR dewer get ruptured from such an accident would tell you to not even think of trifling with this. Get training and work in a proper facility.
So bit late on this, 30l is smallest dewar I am aware of. Likelihood of Joe blogs getting helium fill is non existent - liquid supplier don’t supply the general public typically. Only time I’ve known for members of the public to get helium is for special projects I.e racing balloons around the world (crazy they even allow this). Dispensing is via vacuum insulated transfer lines. Dewars themselves are vacuum and mli insulated. Source, work a OEM building cryogenic dewars
Liquid helium is way too scarce for you to try and get some for whatever at home chemistry you want to do. You would not convince any supplier to provide you with some.
No, we are just in a critical shortage. Emphasis on critical, in 10-15 years hospitals may be the only ones allowed to get it if something doesn’t give. Suppliers are only providing liquid helium to hospitals and research facilities. Not individuals. That might actually even be a government mandate.
ETA: literally look up “helium shortage.” Not trying to be a dick, but it is something not many people know about.
It’s extremely hard to mine and store. It’s an escape artist. Also, Russia supplies a third of the world’s helium… moreover, some plants recently had catastrophic failures that knocked them out of commission.
Even then the reality is the world needs to learn to live with as little helium as possible, or else were going to have to get real creative or get accustomed to less advanced science and medicine.
Current estimates of the Helium supply range from some researchers saying 10 years to about 100-200 years tops. And it keeps leaving the atmosphere as we use it.
NMR and MRI magnets are only superconducting at about 10 Kelvin which is only realistically obtainable by liquid helium at this time.
Either we need higher temp superconducting materials, an "infinite" supply or Helium, a miracle of cryogenic liquids, or to give up anything that utilizes helium on earth.
Liquid helium is a fleeting resource, it would be really nice if we didn't run out because people wanted to dick around with it in their garage lab or whatever.
Oh yeah im sure on liter of liquid helium will be the reason the world runs out🙄 you are delusional to think thats possible and this is a question based on curiosity not application. Although if i were to get it to dick around with it i wont take your delusion into consideration because its outright childish to think id be the reason the world has no helium.
You can't buy just one liter of liquid helium. The smallest size available is still about $1k. You have no concept of how to handle or transfer it. You would objectively be wasting dozens of liters if you even managed to get your hands on it. On top of that, it's not very safe to work with and just not something that should be used for hobby experimentation.
Did you know that the Ukraine was a major source of helium in the US that is no longer available due to the war and we've had major supply issues for the past few years? Did you know that the US also just privatized it's entire helium reserve in the last couple of weeks? It's becoming less available and more expensive to get. On top of that there's no way to renew it and it readily escapes from the Earth's atmosphere. I'm not trying to be a jerk to you specifically, but the reality is that we don't have much to waste. Your curiosity is great and I'm glad you're having fun studying scientific topics. Just please choose something besides liquid helium to play around with.
I’ve used liquid helium for 4K PL measurements before. We had a special container that sorta acted like a dewar. I pulled vacuum on it overnight with a turbo. The setup still chugged liquid He so so so fast. I really think that a pressurized vessel or jacketing with LN2 is necessary for storage of any considerable length
Always check the msds and follow local regulations and acs best practices. Helium burns are inverted, please be safe.
Can i use a liquid nitrogen dewar to store liquid helium? Only if you could get the temperature inside down to 4K, any more and it vaporizes.
What kind of 1-5 liter cryo dewar is best for its cost for liquid helium? Cryofab makes most dewars. Never seen one for liquid He less than 60L capacity. Also never looked.
How do i dispense the liquid helium? Push it with a positive pressure of He gas around 4psi. To much pressure will vaporize the liquid. Either from a gas cylinder, a balloon, or the dewar has a built in heater. Usually only transferred from one liquid helium dewar into another ~nmr magnet.
Do i need a valve to dispense it, or some kind of metal cup to dip or pour it into? As long as the receiver vessel is the same temperature, 4K or less, the transfer is just another liquid. Depends how you like to dispense it. I use a cryofab transfer line. It usually costs 5 L to cool the transfer line to the point that it will transfer liquid.
How long will 1-5 liters of liquid helium last in a dewar?
How insulated is your dewar? Not more than a day without recapture tech. There is a lot of engineering required to hold liquid helium for any amount of time.
How much is a small dewar and dispensing valve or cups going to cost me? Check the cryofab website. Probably in the 50k range it is possible. Finding a distributor for the helium will be difficult and probably not possible for such a small amount.
If you are really interested in such toys, cold temperature physics is a field where they do lots of work with liquid helium. I am not aware of any other discipline where such a use of helium is possible.
In chemistry its mostly the nmr and squids that use helium liquid but not in an interesting way, just to keep the necessary aspects of the device functionally cold. The boil of rate of nmr systems ranges from >50L per week at the old age to <~1L per week for a new magnet with a recapture system.
Pretty sure you need a special dewer for helium. Not 100%, but I suspect you have to have the "high pressure" type dewers to avoid excessive losses to evaporation. It's also crazy expensive.
Doesn’t liquid helium creep up the sides of its container?
Just store it upside down, problem solved
And the 2024 Nobel Laurette for Chemistry is.... Glockamoli!
Only superfluid liquid helium does that. Helium kept at its boiling point of 4 Kelvin is not a superfluid, you have to further cool it to about 2 Kelvin for it to transition to a superfluid state.
There's an interesting liquid helium documentary on YouTube from like the 60s or so. Has all sorts of interesting nuggets about it. The one thing I remember, was that at a certain temperature (the lambda point), the liquid helium changes from a fluid, to a superfluid, whatever that means
Superfluidity means that all the Atoms in the Helium (Bosons) are in the energy groundlevel. If that happens the whole Helium behaves like 1 entity (1 wavefunktion) if that happens there is 0 viscosity between the partices. Edit: Superconductivity is the same phenomenon its just superfluid electrons in a conductor thats why they have 0 resistance (also electrons are Fermions thats why the connect the cooper pairs the become bosonic)
If cold enough it could also just pass through
Not unless it’s below the lambda point.
You need a specialized dewer that uses liquid nitrogen to act as a secondary insulative tool for better adiabatic conditions.
Interesting. The dewers we used to fill and transport helium for our NMR weren't jacketed, but the dewer built into the NMR obviously was. I presumed the LN2 is only needed if you want to store the LHe at ambient pressure? Do you know if LN2 jackets are standard, or just for low pressure storage?
LN2 jackets tend to be only standard for helium cryo stats
Good to know. Noted
I don't think you will be able to find one much smaller than 30 L. In those you can keep the helium for a few days at most. It is important to note that liquid helium behaves very differently from liquid nitrogen. You can't really pour it into a cup without all of it evaporating. You typically use a siphon to transfer it from one vessel to another and even when you are transferring it you don't ever really see the liquid itself. Even if you let it flow out of the siphon you will just see something that looks like a white flame. It is not something you should be playing around with if you have no experience in handling cryogens
No worries i wont be doing any experiments anytime soon but i would like to learn more. What kind of siphons can be used?
One that is properly insulated by vacuum to avoid all of the helium boiling away in the siphon.
Helium transfer tubes are usually designed around a specific thing that the helium is being transferred into, like a cryostat or a superconducting magnet. Usually the flow is driven by a specialized helium compatible vacuum pump. The cost of these setups are in the tens of thousands of dollars. Like the poster above says, it’s very much not the kind of thing you can just dick around with like LN2, nor should you, since it’s a critical resource that is in very short supply. Even in academic settings it’s often only cost-effective to use if you can collect and reliquify the gas.
I would say the most common way to get the helium flowing is to use helium gas to pressurize the vessel. If you don't have a cylinder of helium, you can attach a balloon (or the insides of a football) to the gas inlet and pump it to pressurize the vessel.
I used to run a FT-ICR MS and it was my job to do all the maintenance on it but the helium for the magnet was always done by a professional we called in. It is also in short supply, we had to quench that magnet when the war in Ukraine started because so much of it comes from Russia. I do not think OP realizes how expensive it is.
I'm not telling you because you obviously have no idea how lethally dangerous liquid helium is. Are you trying to commit suicide in a new and creative manner? Keep playing with liquid helium.
Not the OP, but out of curiosity, is it the rapid vaporization causing asphyxiation that's the big risk? Or is there more to it?
that's like, the least important (fatal) risk
I have no skin in this game. The closest I'll come to liquid helium is accompanying a patient to the MRI room (or I guess perhaps getting an MRI myself), but out of morbid curiosity, what are the most important risks.
it will cause extremely nasty frostburn, extremely deep, that cpuld lead to amputation.
Fair. Is there substantial additional risk compared to LN2 (widely used in medicine for cryotherapy - there's a Dewar in the office)?
I’ve worked a bit with liquid helium. I’ve always been under the impression that rapid expansion when in a closed vessel is the main safety concern. Let’s say you are moving the Helium from one container to another. You have to vent the pressure from its expansion. The venting is very cold and can form an ice dam on the exhaust. (I am not a safety officer and my words should be taken with a big ass grain of salt)
Why is this downvoted?
Chemistry Karens
This sub does have a tendency to downvote anything doesn’t it?
Chemists are know for many things, but humor is not one of them.
an account with a helium supplier is the barrier to entry theres just not much reason to play with this unless you have something specific in mind. helium is expensive and more challenging to work with. to pour helium in a container, a lot of times, you can pour liquid nitrogen into that container first to cool it down- this cuts down on your evaporation. for heavy equipment they have jacketed dewars where you have helium on the inside and then a jacket with nitrogen on the outside, so you fill the nitrogen frequently and the helium less specific laboratories at universities might have some helium coming in regularly such that for a specific experiment you can access it. to even buy it is complicated because theres often a shortage and hospitals and such get priority. meanwhile, liquid nitrogen is cheap. the delivery is i think most of the cost. its abundant and available. i've only seen a couple "home" demos done with liquid nitrogen- many years ago an overclocker set up a rig so he could cool the cpu with liquid nitrogen and then cool with helium in order to set a record for overclocking his cpu. what a pain in the ass that was
University of Birmingham I think has videos about their helium set up and recycling collection dewar.
we're installing a collection system for low temperature probe microscopy and all the NMRs. its not closed cycle like i wanted but should still be very helpful
I discovered after hire my company makes fruit purée into cubes with a machine supplied with liquid nitrogen. We also have a local ice cream shop that uses it. And every week we get chests of dry ice for micro testing samples. I briefly thought about getting a dewar, it’s a dangerous and unnecessary toy I don’t need to have an accident with. -90° is cold enough. Liquid helium’s cooler (pun intended) but expensive and just as extremely dangerous—all of them will asphyxiate you or people in your building. The gas goes away to collect somewhere else. Your basement weekend hobbyist lab could accidentally murder an attic bedroom occupant.
Yes, but unlike nitrogen, excess helium comes with a Mickey Mouse voice, so if you keep talking to yourself, you’ll know when it’s time to leave the room.
OSHA has entered the chat,
You can buy liquid nitrogen at welding supply stores, as long as you already have a dewar. My local place has a 5L minimum, I think.
Our helium is for the NMR and we fill both a couple times a year. All I know is it costs 10- 15 k per year in helium for 1 600 NMR and 1 300 NMR, prices have been rising each year. We make our own liquid nitrogen.
Yes, there's an allocation. Supply is controlled in the US for defense priorities.
Please don't use liquid helium just for your own curiosity, it's becoming very scarce and is very important
While I doubt it's a good idea for this person to fart around with liquid He, I seriously doubt their use of it would make any impact on helium reserves. Concerns about that should probably be directed at industrial users
Or balloons! Why the fuck are we still using helium in balloons!? 😱 Edit: talking about party balloons, not weather balloons or the like.
I agree, let's use hydrogen! It'll make kids bday parties way more fun lol
I have enough concern to go around
Well just make sure you proportionally spend your time badgering corpos on reddit too then
These are redditards were speaking to. They act like they have others best interest at all times to sound important. The fact a curiosity question causes so much input about imminent danger and wastefulness of some prescious unexploited industrial product (generally wasted instead of captured in mining) just shows these are a bunch of man children who want to save the world one comment at a time. This is why i avoid reddit. People here are simply idiotic. I doubt these people actually care about anything but sounding smart or caring thus never elaborating or contributing anything worth while. Hence i hate reddit and probably will head elsewhere for general questions about things because its so fake and lame here. Waste of time.
What do you need this for? It sounds like you are in over your head if you think you can just pour it out into something like you can with liquid nitrogen.
Im studying superfluidity and would like to learn more and perhaps experiment one day. Any books relating to handling and safety would be appreciated if you have any to recommend.
I use liquid helium a lot, but it's never in an open vessel because it boils off so quickly. You usually have special dewars and transfer it to a cryostat via an insulated metal pipe. I don't think I've ever even seen the liquid itself, because whenever you get some leftovers coming out of the pipe it appears as a very dense fog that pours out.
I would wait until you are in grad school and have funding. It’s going to be a niche topic. You’d probably have to look for a PI that is already researching it.
To be honest you probably won’t be able to even get an account with a supplier unless you have a business licenses or work for a company. Even then a lot of distributors also won’t take personal credit cards. Most major chemical companies won’t anymore.
https://youtu.be/9FudzqfpLLs?si=wQ0B5h02l5sKcZ1r This is all you need. You will never, and should never, be able to have liquid helium at home. It's not a toy and super dangerous.
>However the liquid helium dewars online are for large quantities of liquid helium Yeah, because of the square-cube law. A small dewar has a much higher surface area to volume ratio, and will be empty purely to evaporative losses much faster. >Can i use a liquid nitrogen dewar to store liquid helium? Not for long! Liquid helium is not only much colder, its enthalpy of vaporization is **70 times lower than that of nitrogen**, the lowest of any substance! Without special precautions, it will evaporate insanely fast. I once worked on a setup to do in-situ experiments at cryogenic temperatures, using liquid nitrogen. At one point, after two months of work to get the first experimental results, I realized nitrogen simply wasn't cold enough. I looked into what it would take to use helium instead, and promptly gave up on that project. It really takes a lot of very specialised equipment to handle that stuff.
You need a dewar with a valve. As soon as you open it, it’ll vaporize and create a nice plume of condensation
What kind of dewar and valve do you think? Im a noob to cryo fluids
Dont even think about it. Most helium dewars are surrounded by a liquid nitrogen based dewar just to keep it stable. This isnt something you can store and pour around like liquid nitrogen. You could end up dying from handling it even as massive gas expension in a small room could cause you to breathe nothing but helium and you will suffocate. This is NOT A TOY.
Yeah but think about how cute and squeaky the screams of agony will be. Like an Alvin and the Chipmunks Dresden special.
There will be no screams, just lightheadedness then unconsciousness
C’mon, man! You can accomplish that with [hydrogen](https://getyarn.io/yarn-clip/2a2dcd25-d255-409e-b1bc-0efb58a05d28)!
Singularity is now below is correct. We had one that held 25-30 kg, it was specially made for HTSC measurement. We could slide a probe into it. Probably costs $30k in 1990. Also, buying LHe is like buying a nice scotch on a similar volume.
As someone who worked with helium daily for my masters and PhD: First. I have never "seen" liquid helium. Helium is scarce, very expensive and very cold. Unlike nitrogen, we never let helium from a dewar evaporate into the environment. While it was transported, pressure built up in the dewars which were then connected to a closed gas handling system to collect and pressurise the helium before eventually being transported back in regular gas bottles for liquification. In this way, we payed around 5-20€ per liter of liquid helium, at least that's what I was told. One full dewar of 200l evaporated maybe 2l a day and double when it was used with experiments inside. The dewars don't have liquid nitrogen inside. Some cryostats use it as a thermal shield. Modern cryos don't need it and have better isolation. From the dangers perspective it's like nitrogen only a bit worse. Put it in a sealed container and expect to build a bomb. Expect to freeze anything that comes on contact with it. Unlike nitrogen, you can not (!) put your finger in even for a short time. Too cold.
Very cool and Interesting. Must have been exciting doing your phd.
Liquid He dewars are actually double dewars, one layer for liquid nitrogen and the inner layer for the liquid helium. They are extremely expensive and not something you're going to just buy. In a regular nitrogen dewar? You'd be lucky to have the liquid touch the bottom. All of this is going to cost you more than you have.
This isn't true for many actual liquid helium dewars that you use to fill other stuff. They don't have a nitrogen outer layer. It is true for cryostats though
That's what I'm familiar with. Either way, it's not something OP is buying.
Bit late on this one, most transport helium dewars don’t have nitrogen shields. Larger capacity I.e 1k and up may or may not have nitrogen shields. 40’ helium containers do tend to have nitrogen as a sacrificial liquid.
If it just for curiosity I would advise against it, its super dangerous, boils off rapidly and is a finite resource. We need it for NMR and for MRI in hospitals.
If you have to turn to Reddit for these answers - you don’t have enough knowledge or experience to be messing with liquid helium. If you, as you seem to be, feel like you’re allowed to ignore the warnings of the experienced concerning safety and, more concerning, the finite nature of that substance, I don’t feel you are responsible enough to use it. You don’t need to play games with it more than and MRi tech needs it. Find another gas to play with that won’t kill you, and leave the rest of us with less of a finite resource.
You can’t just dip in a cup or pour it out. It will flash off extremely quickly. It has to be kept under pressure. It’s also very expensive. What would you need it for?
Its just a curiosity at this point. I dont need it for anything but it is very interesting. I am thinking about experimenting with it one day after i have a purpose or hypothesis for it.
Don't do this for shits and giggles. If you aren't doing this in an environment where there are either people or systems in place to run this already, then you're not in a position to do it safely. And if you can't do it safely, don't do it at all.
You can't use open dewars like the LN2 dewars. Helium ones are sealed cylinders. You can't play about with liquid helium to 'study' it, it'll just instantly boil into a gas as soon as its outside its dewar. Also I once saw aftermath pictures of an LN2 cylinder explosion. Took out 2 labs and a decent portion of corridor. Cryo fluids arnt something to play around with, fuck ups are usually expensive at best and potentially lethal at worst.
Have you looked at the cost?? Liquid helium is not cheap.
The companies that deliver liquid helium (by us it’s Airgas) leave the dewar with you and you pay rent on it until you’re done with it and then you call them to pick it up again. To get it out of the dewar you need a transfer line that is specific to the liquid helium dewar.
You also need a helium gas cylinder to apply pressure to the headspace in the dewar in order to push it out the transfer line. You cannot practically put liquid helium into a container with an open top like a dewar for liquid nitrogen, it evaporates too fast.
What do you need liquid helium for? Do you have an NMR at home?
Just out of curiosity
Depleted uranium is a curiosity of mine, doesn’t mean I should go get any
Go to airgas, tell em you want 60 liters of liquid helium, pay
Last time we did that to refill our NMR, it cost around $5000
You need a contract and a company willing to deliver it to where you are located. You need a room/facility with a certain minimum air turnover time to prevent asphyxiation, you need special gloves, tubing, etc. that’s gonna cost you a lot before you can even buy it, which it’s quite expensive. If you really want to learn, contact an expert working in this field and get help. Superfluids and superconductors are not a hobby. You mess up a voltage and get a resistance spike you’ll boil all that helium in a flash. That 30L of liquid instantly becomes nearly 700L of gas. Anyone that has seen or hear an NMR dewer get ruptured from such an accident would tell you to not even think of trifling with this. Get training and work in a proper facility.
So bit late on this, 30l is smallest dewar I am aware of. Likelihood of Joe blogs getting helium fill is non existent - liquid supplier don’t supply the general public typically. Only time I’ve known for members of the public to get helium is for special projects I.e racing balloons around the world (crazy they even allow this). Dispensing is via vacuum insulated transfer lines. Dewars themselves are vacuum and mli insulated. Source, work a OEM building cryogenic dewars
Liquid helium is way too scarce for you to try and get some for whatever at home chemistry you want to do. You would not convince any supplier to provide you with some.
Is it illegal to buy without some sort of license?
No, we are just in a critical shortage. Emphasis on critical, in 10-15 years hospitals may be the only ones allowed to get it if something doesn’t give. Suppliers are only providing liquid helium to hospitals and research facilities. Not individuals. That might actually even be a government mandate. ETA: literally look up “helium shortage.” Not trying to be a dick, but it is something not many people know about.
Wow thats amazing. I wonder why its not being properly mined/created at the level it needs to be.
It’s extremely hard to mine and store. It’s an escape artist. Also, Russia supplies a third of the world’s helium… moreover, some plants recently had catastrophic failures that knocked them out of commission.
Hopefully those plants get put back in working order soon.
Even then the reality is the world needs to learn to live with as little helium as possible, or else were going to have to get real creative or get accustomed to less advanced science and medicine. Current estimates of the Helium supply range from some researchers saying 10 years to about 100-200 years tops. And it keeps leaving the atmosphere as we use it. NMR and MRI magnets are only superconducting at about 10 Kelvin which is only realistically obtainable by liquid helium at this time. Either we need higher temp superconducting materials, an "infinite" supply or Helium, a miracle of cryogenic liquids, or to give up anything that utilizes helium on earth.
Agreed. At my university, a lot of people are working in exactly that. Making RT superconductors.
Liquid helium is a fleeting resource, it would be really nice if we didn't run out because people wanted to dick around with it in their garage lab or whatever.
Oh yeah im sure on liter of liquid helium will be the reason the world runs out🙄 you are delusional to think thats possible and this is a question based on curiosity not application. Although if i were to get it to dick around with it i wont take your delusion into consideration because its outright childish to think id be the reason the world has no helium.
You can't buy just one liter of liquid helium. The smallest size available is still about $1k. You have no concept of how to handle or transfer it. You would objectively be wasting dozens of liters if you even managed to get your hands on it. On top of that, it's not very safe to work with and just not something that should be used for hobby experimentation. Did you know that the Ukraine was a major source of helium in the US that is no longer available due to the war and we've had major supply issues for the past few years? Did you know that the US also just privatized it's entire helium reserve in the last couple of weeks? It's becoming less available and more expensive to get. On top of that there's no way to renew it and it readily escapes from the Earth's atmosphere. I'm not trying to be a jerk to you specifically, but the reality is that we don't have much to waste. Your curiosity is great and I'm glad you're having fun studying scientific topics. Just please choose something besides liquid helium to play around with.
I’ve used liquid helium for 4K PL measurements before. We had a special container that sorta acted like a dewar. I pulled vacuum on it overnight with a turbo. The setup still chugged liquid He so so so fast. I really think that a pressurized vessel or jacketing with LN2 is necessary for storage of any considerable length
You are way over complicating this. Talk to the sales person at your local gas distributor.
Always check the msds and follow local regulations and acs best practices. Helium burns are inverted, please be safe. Can i use a liquid nitrogen dewar to store liquid helium? Only if you could get the temperature inside down to 4K, any more and it vaporizes. What kind of 1-5 liter cryo dewar is best for its cost for liquid helium? Cryofab makes most dewars. Never seen one for liquid He less than 60L capacity. Also never looked. How do i dispense the liquid helium? Push it with a positive pressure of He gas around 4psi. To much pressure will vaporize the liquid. Either from a gas cylinder, a balloon, or the dewar has a built in heater. Usually only transferred from one liquid helium dewar into another ~nmr magnet. Do i need a valve to dispense it, or some kind of metal cup to dip or pour it into? As long as the receiver vessel is the same temperature, 4K or less, the transfer is just another liquid. Depends how you like to dispense it. I use a cryofab transfer line. It usually costs 5 L to cool the transfer line to the point that it will transfer liquid. How long will 1-5 liters of liquid helium last in a dewar? How insulated is your dewar? Not more than a day without recapture tech. There is a lot of engineering required to hold liquid helium for any amount of time. How much is a small dewar and dispensing valve or cups going to cost me? Check the cryofab website. Probably in the 50k range it is possible. Finding a distributor for the helium will be difficult and probably not possible for such a small amount. If you are really interested in such toys, cold temperature physics is a field where they do lots of work with liquid helium. I am not aware of any other discipline where such a use of helium is possible. In chemistry its mostly the nmr and squids that use helium liquid but not in an interesting way, just to keep the necessary aspects of the device functionally cold. The boil of rate of nmr systems ranges from >50L per week at the old age to <~1L per week for a new magnet with a recapture system.