Sciencemadness Discussion Board

compressed Nitrogen

Domo_Kun - 17-11-2011 at 11:51

I was wondering how people flushed their aparatuses with inert gases at home. Where does one get compressed nitrogen?

Magpie - 17-11-2011 at 18:37

Check the compressed gas dealers in your area. You should be able to buy or rent either argon or nitrogen cylinders of various capacities. I bought a 40 ft^3 cylinder of argon which I can get refilled anytime. You will also need a pressure regulator, which you can get for around $50.

fledarmus - 18-11-2011 at 05:29

Almost anybody that sells welding gases will also sell inert gases. In most places (at least in the US) there are enough garage mechanics that the welding stores don't have a problem selling the gases to private citizens, although I have known outfits that refuse to deal with anybody that doesn't have a contractor's license. Basically you pay a deposit and rental fee on the cylinder and buy the gas inside it - you return the cylinder when it's empty and they give you a fresh one.

Be sure you have a safe way to transport the cylinder.

EDITED to add the following demonstration:

Mythbusters - gas cylinder

because it was cool

[Edited on 18-11-2011 by fledarmus]

Domo_Kun - 18-11-2011 at 13:16

Thank you for your answers
cool video indeed, fledarmus :)

Takron - 19-11-2011 at 00:01

Paintball also uses nitrogen for some of the systems. You can look into getting a paintball tank of nitrogen if you don't want a large cylinder hanging around. Depending on how much you use. You can get them filled anywhere that handles nitrogen.

Mr. Wizard - 19-11-2011 at 15:45

Quote: Originally posted by Takron  
Paintball also uses nitrogen for some of the systems. You can look into getting a paintball tank of nitrogen if you don't want a large cylinder hanging around. Depending on how much you use. You can get them filled anywhere that handles nitrogen.


Most older paintball systems I've seen use CO2. Is there a newer system that uses N2?I have filled my son's paintball cylinders from an inverted CO2 tank. Typically the pressure is lower in a CO2 tank at normal temperatures , while N2 tanks are 2 or 3 times as high, requiring a stronger tank. The technology might have improved, just asking.

Takron - 19-11-2011 at 21:43

Quote: Originally posted by Mr. Wizard  
Quote: Originally posted by Takron  
Paintball also uses nitrogen for some of the systems. You can look into getting a paintball tank of nitrogen if you don't want a large cylinder hanging around. Depending on how much you use. You can get them filled anywhere that handles nitrogen.


Most older paintball systems I've seen use CO2. Is there a newer system that uses N2?I have filled my son's paintball cylinders from an inverted CO2 tank. Typically the pressure is lower in a CO2 tank at normal temperatures , while N2 tanks are 2 or 3 times as high, requiring a stronger tank. The technology might have improved, just asking.


Yeah, it is the preferred method for most professional players and serious hobby players. The higher pressure keeps a more stable shooting velocity for more accurate firing over time. the tanks are really round compared to CO2 tanks.

zoombafu - 22-11-2011 at 00:39

Im interested as well in maintaining an inert atmosphere for reactions, so if someone could point me somewhere useful it would be greatly appreciated.

edgecase - 22-11-2011 at 18:38

I've been considering CO2 for less demanding "inert" applications, purging water and oxygen before nitric acid synthesis for example. I have access to both argon and CO2 cylinders already, which I use for welding, as well as an adjustable regulator. Why not just go for the argon then? Price. the CO2 is liquid, thus more "moles" fit in the cylinder. For welding it's certainly cheaper, so I assume it is also cheaper for chemistry.

How do you get nitrogen cylinders?

thebean - 13-2-2014 at 14:29

I have been wondering for some time now how I can get my hands on nitrogen for the purpose of flooding vessels during syntheses that require inert atmosphere. I figure that some people buy it. I'm located in the USA if that helps to narrow things down.

cyanureeves - 13-2-2014 at 15:21

dude they should have them at your local welding supply store.helium also acetylene and oxygen.

thebean - 13-2-2014 at 15:34

Your "Dude" would suggest that you think I'm an idiot or something. I've never been to a welding store before so I wouldn't know that. None the less your help is appreciated.

[Edited on 13-2-2014 by thebean]

bfesser - 13-2-2014 at 15:47

Quote: Originally posted by thebean  
Your "Dude" would suggest that you think I'm an idiot or something. I've never been to a welding store before so I wouldn't know that.
Well, if you had tried the search function, you <em>would</em> have known that. (That's my polite way of saying UTFSE.)

thebean - 13-2-2014 at 16:04

I Googled it and didn't find a whole lot. I didn't know that nitrogen was used for welding and thus didn't think of that. I'm sorry I don't know everything.

cyanureeves - 13-2-2014 at 16:36

sorry the bean i had no idea you could surmise all that off one tiny word but you are welcome.what really matters is that you get your nitrogen and from now on i will use "hombre" instead of dude:D.Naw! i'll just use thebean instead.

Magpie - 13-2-2014 at 16:40

http://www.sciencemadness.org/talk/viewthread.php?tid=18034#...

http://www.sciencemadness.org/talk/viewthread.php?tid=10366#...

thebean - 13-2-2014 at 18:30

I'm sorry that I jump to conclusions like that, I'll try to correct the behavior, and while I'm at it UTFSE more often.

alive&kickin - 16-2-2014 at 18:09

Bean, for what it's worth, you can get the nitrogen in welding supply shops in different size cylinders as long as moisture isn't a problem in your experiment. If you need dry nitrogen, go to one of the specialty gas places, Airgas etc, as they contain little to no moisture. That's where I go for my work, maintaining buried lead lined cable that has copper wire that is paper insulated, we keep it pressurized with dry nitrogen to keep the ground water out.

Zyklon-A - 16-2-2014 at 19:04

Or you could just hook up a CaCl2 tube to the N2 output, bubble through concentrated sulfuric acid, or use one of many other ways to rid you N2 of H2O vapor.

[Edited on 17-2-2014 by Zyklonb]

Refinery - 17-2-2014 at 12:15

Technically you can inert the apparatus with any gas that does not react with the reactants and is not an oxiziser. Propane gas would work for most part.

Metacelsus - 17-2-2014 at 15:22

The thing with propane is that is causes explosions if you are not VERY careful (and even then accidents happen).

Refinery - 17-2-2014 at 22:43

The good thing about propane is that it's lower and upper explosive limit is 2.3-9.5%, so you will enrich the air composition inside the container very quickly, and therefore render it unable to sustain fire. Naturally, the apparatus needs to be somewhat air-tight, but in my case this is a lot easier - and cheaper - to come by than to buy nitrogen cylinders. Actually, I can buy at least two full sets of glassware with the price of one nitrogen cylinder. As long as the pressure difference is ~0 inside the app, or you flow in a slight amount of propane and lead the fumes to burner or outside with tubing, the risk is very low. Propane gas is very cheap and readily available in many different sizes.

Of course, if you were in need of inert gas, eg. welding - like argon I do - you can use it "for free" for this purpose. :D Argon is yet better, because it suits for *everything*, where nitrogen likes too much of some compounds, like alkali metals. :P

yobbo II - 23-3-2017 at 12:13

When you buy a tank (bottle) of CO2/Argon mix from you welding supply is the CO2 in liquid form and the Argon a gas? all in the one bottle?

How do the two gases end up being equally mixed as they come out. Would all or at least a gas with a higher concentration of Ar not come out first and leave the CO2 to come out last.


Lastly is is safe to take a new bottle of Argon/CO2 welding gas and transfer all the contents into another (suitable) bottle by joining up the bottles with a suitable pipe + connectors and inverting the new full bottle and placing it on top of the empty bottle thus allowing the contents to flow or move (liquid + gas or whatever) into the lower bottle.

TFYT

Yobbo II

adk - 23-3-2017 at 20:30

I have been using Nitrogen in the past but found a supplier for relatively inexpensive 5N Argon, so I'll be using Argon now that my Nitrogen cylinder is empty.

For about two years I was using a hose connected to a 29/32 gas inlet adapter, now i'm using balloons with a cut off syringe, needle and rubber septa. It's much more efficient to use this method rather than just pump gas into the flask continuously. Once it is flushed and the solvent degassed, you don't actually need much inert gas flow - just enough to displace air from the system.

Next time I run a reaction, i'll take a photo