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I need some kind of propellant gas for an experiment

  1. May 22, 2015 #1
    For the past year or so, I've been experimenting with Isobutane. I used to get it in relatively cheap canisters of r600a from amazon.co.uk and AliExpress, and that worked fine. Now, however, AliExpress has NO purchase options for r600a, and amazon.co.uk will not ship it to the US, even though they used to do it for me. This is really bugging me. I cannot find any information about the laws of isobutane in the US, at all. Has it been banned? I don't know. Either way, I need something to replace it for my experiments if I can't find a place that sells it.

    The kind of gas I'm looking for is one that can be sold in small canisters at a relatively cheap price, not big cylinders. I want it to have a vapor pressure of at least 30 psi (~200 kpa) and have a boiling point of around 0°-30°F (not near room temperature). As you can see from these conditions, Isobutane was absolutely perfect. But, now that I can't get it anymore, so these are the gases I've looked at.

    HFC-227ea - Looks promising. It is not very toxic. I'm not using high temperatures, so is it a big issue that it can turn into hydrogen fluoride at high temperatures? Another problem is I can't find it sold in small canisters. I think it is the propellant in some Inhaler cartridges? But if I get it in the inhaler cartridges, it would also have the medicine in it too, right? That might be a problem.

    Butane - Looks equally great. It has a boiling point of about 32°F, a little high but I'm willing to look past it if its my last option. It is sold in canisters (as fuel, kinda iffy). I don't plan on lighting it on fire, but theres always the risk. Then again, there was that risk with isobutane also. Its easy to get, and I doubt it'll disappear like r600a. Two questions: Is the inhalation risk bigger than it was with isobutane? And should I be worried that If it did catch on fire, nitrogen dioxide would be created?

    Isobutane/Propane Blend - This is also very available. It is fuel of course, and it is a blend, so I can't find any information on what temperature and pressure it condenses at, but I'm willing to try if someone else says it might work. I don't like the propane part, but in some cases thats only 20%, but it does have a bigger health hazard than isobutane.

    This is just a compilation of facts that I've put together. I thank anyone who took the time to read all that stuff, and especially thank those who have something to add (and if anyone knows a way to get back to buying isobutane like I used to, it would be much appreciated).
  2. jcsd
  3. May 23, 2015 #2


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    Did you try mountaineering shops or the store locator of gas providers like campingaz?
  4. May 23, 2015 #3
    I checked it out. It has something called isobutane mix which I'm guessing is the isobutane/propane stuff, but it doesn't look like they sell from their website and the nearest store is two states away.
  5. May 23, 2015 #4


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    The properties of R600a are here:



    Isobutane is supplied by companies like Linde and others who are in the business of industrial gas supply.


    If you are in the States, IDK why you went all the way to the UK to get this stuff.
  6. May 23, 2015 #5
    How do I buy from Linde? I don't see how.

    EDIT: They have 0 locations in the US
  7. May 23, 2015 #6


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    Linde is one of the biggest suppliers of industrial gases in the US. You see their trucks hauling product all over the roads.

    Here is the website for their US subsidiary:


    You may not be able to buy from Linde directly, but odds are they will supply local distributors and retailers. It might take a bit of detective work, maybe even a trip through the yellow pages, but if you live near any reasonably sized city in the US, someone is going to be using oxygen, acetylene, nitrogen, etc.

    R600a was once used as a refrigerant. If there are any businesses which sell or service air conditioners or industrial refrigeration systems in your area, call them. They may be able to furnish you with a supplier contact if they can't help you directly.
  8. May 23, 2015 #7
    Hm, okay, thanks. I'll see what I can find!
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