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Topic: How to turn LN2 into N  (Read 9660 times)

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Offline DevaDevil

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Re: How to turn LN2 into N
« Reply #15 on: March 31, 2011, 09:45:40 AM »
Why would you keep it closed? and how could i add volume to the bag without wasting the N inside of it? ill be using it anyways but im a bit worried about spending all the N inside the bag, and when i need more ill have to wait for it to evaporate and i dont know how much time could it take to fill the bag again....

it evaporates VERY quickly, so little time to wait to fill it up, so you want to keep it closed in order not to waste much of it.


and even easier, as found on wiki (did not check to see if this is right, you may want to do that yourself): "the liquid to gas expansion ratio of nitrogen is 1:694"

Offline DoubleWhopper

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Re: How to turn LN2 into N
« Reply #16 on: March 31, 2011, 12:50:22 PM »
So in one Thermos of 1L filled with LN2 i have 694L of Pure N in gas state?  :D

Thats awesome, then probably 1L will be enough for my experiment :)

I was wondering how much time will take to evaporate all the LN2 into N if i have 1L and its inside the Thermos, i need a steady supply of pure N gas for half an hour or more, and i need to know at what speed it will be converted and how to make it last for 30+ minutes.

Offline DevaDevil

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Re: How to turn LN2 into N
« Reply #17 on: March 31, 2011, 01:32:31 PM »
liquid N2 to gaseous N2 is fast. How fast when you open the top? no idea, sorry.

Offline DoubleWhopper

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Re: How to turn LN2 into N
« Reply #18 on: March 31, 2011, 03:14:05 PM »
No problem, thank you for helping me out with my experiment  :)

Still have to make some tweaks to the final design but i think its going to work as intended  ;)

This would be so easy if i had $1k to get the required equipment.. ::)

Offline DoubleWhopper

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Re: How to turn LN2 into N
« Reply #19 on: April 08, 2011, 06:32:28 PM »
Well everything went out pretty good with the first experiment.

Now i need to spend/turn 1L of LN2 into N2 in 1/2hr-1hr, ive thought about making something like what i've drawn in the first post, but instead of fire, i could put the thermos in a container filled with boiling water or something like a water bath, then attach a valve to the top of it? the thing is i need some pressure now..   ::)
« Last Edit: April 08, 2011, 07:09:38 PM by DoubleWhopper »

Offline Honclbrif

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Re: How to turn LN2 into N
« Reply #20 on: April 09, 2011, 08:17:58 AM »
Do not put the liquid nitrogen in boiling water; see the above comments about bombs.
Individual results may vary

Offline DoubleWhopper

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Re: How to turn LN2 into N
« Reply #21 on: April 09, 2011, 04:19:28 PM »
Well finally as i didnt get any answers yesterday and i was very... excited with the experiment i did it anyways, i submerged the thermos in boiling water for a long time, i needed some pressure but it was a big failure, i didnt get any constant pressure, only intermittent and very low, while i needed a good constant flow of N2.

Im considering to buy one of those tanks, they are around $400, do you think they will provide a constant supply of N2 if i fill them with LN2?

Do i have to put pressure in them? I really dont know how this works at all...

Offline nj_bartel

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Re: How to turn LN2 into N
« Reply #22 on: April 11, 2011, 07:59:50 PM »
You're going to kill yourself.  LN2 is going to take a fairly long time to go to gas while in a thermos... because it's in a thermos.  To increase the rate at which the LN2 becomes gas, experiment by changing to various less insulating containers, not putting your insulating container in boiling water.  Listen to the experienced chemists here (not myself, but the other three posters in this thread).

Offline DevaDevil

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Re: How to turn LN2 into N
« Reply #23 on: April 12, 2011, 10:18:17 AM »
if you are going to spend money, it is probably better to just buy a regulator and compressed nitrogen gas cylinder.

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