evil_lurker
National Hazard
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Mood: On the wagon again.
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Converting paintball tanks for willgerodt and other interesting things...
Well after 4 loong years, I have officially found out what kind of thread is on those cheap 9 oz steel paintball tanks.
Its a National Pipe Thread Straight size 9/16"-18 (threads per inch), which just so happens coinkydinkly to be the same size thread on mose muzzle
loader breech plugs.
But that won't do me much good, so I managed to find a compatable plug made by Parker, part number 6P5ON found on page 12 of their catalog here:
http://www.parker.com/icd/pdf/Pipe%20ISO%20Catalog%204260.pd...
Now then, the question is, what kind of corrosion resistance will the cylinders have in the ammonia/sulfur/pyridine reaction mixture?
I'm thinking that since the 9 oz cylinders are made out of chrome-moly steel, they will be somewhat prone to getting eat up by the ammonia, and will
need some sort of coating on the inner cylinder to provide chemical resistance and/or prvent side reactions.
I'm thinking that perhaps a gold or platinum plating would work, or perhaps teflon.
Any suggestions?
Not all chemicals are bad. Without chemicals such as hydrogen and oxygen, for example, there would be no way to make water, a vital ingredient in
beer.
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Mr. Wizard
International Hazard
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Ammonia and ammonia in water do not corrode steel or iron to any extent when not exposed to oxygen. I say this because propane tank trucks are made of
steel and they are used in the summer time to deliver anhydrous ammonia to farms. Not all propane truck can do this, only those with no copper or
brass fittings or valves, which ammonia DOES attack. Ammonia refrigerators that run on heat from a propane flame are all steel and are full of a
concentrated ammonia solution.
Sulfur also quickly attacks copper and brass as well. I don't know about steel, but I expect it does, especially at elevated temperatures.
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Fleaker
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I'd get a teflon bottle and run it in that. I have some 2L ETFE bottles that are good to 3 bar. I know I posted photos somewhere...
Anyways, you can get them for 50-100 each (or 370 ea from VWR) and they last forever.
Neither flask nor beaker.
"Kid, you don't even know just what you don't know. "
--The Dark Lord Sauron
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evil_lurker
National Hazard
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Yeah I was looking at those... they appear to be made out of some tuff stuff... don't know how they would handle under pressure though.
There was a seller on Ebay that had some 250ml ones for $50 plus shipping.
Another thought is to run the reaction in a stainless tri-clover setup.
I figure a 2" tee would work well, with caps and PTFE seals on all the ends... if not I can still use them on my moonshine still.
Judging by some scematics I've seen, the apparatus would hold approx 300-350ml with 100-150ml of headspace in the middle tee.
I think it woud seal up OK.. I know you can take one of those tri-clover fittings and really screw down on that PTFE seal.. plus when it heats up it
will swell some more making an even tighter seal... worse case scenario add a little paste type PTFE pipe sealant on it.
Heating could be as easy as a small cheap tabletop convection toaster ovens set @ 325ºF for 4-5 hours. That way it could be set up outdoors so that
in case of explosion nothing much would damaged other than the oven itself.
[Edited on 26-1-2008 by evil_lurker]
Not all chemicals are bad. Without chemicals such as hydrogen and oxygen, for example, there would be no way to make water, a vital ingredient in
beer.
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evil_lurker
National Hazard
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And what it looks like when its all put together...
Well what do ya'll think?
[Edited on 1-2-2008 by evil_lurker]
Not all chemicals are bad. Without chemicals such as hydrogen and oxygen, for example, there would be no way to make water, a vital ingredient in
beer.
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Magpie
lab constructor
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Mood: Chemistry: the subtle science.
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That's a nice looking piece of equipment. At first I was wondering why the tee shape. I suppose that is so that gas can collect in the upright
branch and be drawn off there if required. It would also be a good spot for a pressure guage and a thermocouple port. What is the material of
construction? And what do they want for this little beauty?
The single most important condition for a successful synthesis is good mixing - Nicodem
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not_important
International Hazard
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While that certainly is shiny and has a nice industrial feel, I'm going to toss out an idea related to the origins of this thread.
You can get fluorocarbon coating mixtures, and powdered Teflon for lubricating purposes. It might be practical to coat the interior of a paintball
tank to increase its chemical resistance.
To get a full coating you'll likely have to apply and fuse the coating using three different orientations for the bottom, top, and sidewall of the
tank. Surface preparation will be needed, perhaps to the point of abrading the surface. You'll want good ventilation during the sinter heating
phase, unless you seal the tank, as fluorocarbon vapours are somewhat toxic.
I don't know enough about this to say how practical it might be, could be totally outside of what could be done in a home workshop setting.
http://www2.dupont.com/Teflon_Industrial/en_US/products/prod...
[Edited on 2-2-2008 by not_important]
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evil_lurker
National Hazard
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The entire thing is made from 304 stainless, except for the two "U" bolt assemblies that make up the stand. I think the fitting is rated as being
150psi at room temp, who knows how it will perform under pressure and corrosive chemicals.
Total cost of the apparatus is about $80 including shipping. I already had several fittings for use on my moonshine still so it wasn't too bad. A
replacement tee will set ya back about $20-25.
I really wanted one made out of 316 and a solid coupler, but those are about as common as frog hairs.
Not all chemicals are bad. Without chemicals such as hydrogen and oxygen, for example, there would be no way to make water, a vital ingredient in
beer.
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bio2
Hazard to Others
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This is the type of Teflon coating that will cure at home oven temps.
http://www2.dupont.com/Teflon_Industrial/en_US/products/sele...
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