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Author: Subject: Birkeland-Eyde reactor for making nitric acid.
Hermes_Trismegistus
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[*] posted on 23-2-2004 at 22:44
It's been explained to him......


how he could quantitatively measure the amount of acid produced by going out and getting a packet of rolaids and head of purple cabbage.

It seems he's just insane,

He's resourceful, intelligent and dedicated.....but utterly lacking in the sense God gave the common dog.




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[*] posted on 23-2-2004 at 23:45


Quote:

It's been explained to him......

how he could quantitatively measure the amount of acid produced by going out and getting a packet of rolaids and head of purple cabbage.
It seems he's just insane,

He's resourceful, intelligent and dedicated.....but utterly lacking in the sense God gave the common dog.


I do have litmus paper. Lots of it.

And come on, the gas wasn't even brown.....

Besides, human lungs can take a lot more than one would think. I feel fine. Honestly.

And having had 2 dogs, I can vouch for the fact that I do have at least some more common sense than a dog. And if sense is so common, why do we see so little of it?

Edit: Btw, the reactor bottom is cooling now. Once the oven hits 80C, I'll pick it out and take some shots.

Edit2: And I'm not suffering from insanity, I'm enjoying every minute of it!


[Edited on 2004-2-24 by axehandle]

[Edited on 2004-2-24 by axehandle]

[Edited on 2004-2-24 by axehandle]




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[*] posted on 24-2-2004 at 01:45


Hahahaa.

But you really should treat your lungs with a bit more respect. I respect mine ALOT more now, after having gone through over a week of pain from HCl/Cl2 poisoning feeling like I continuously could not get enough air :D

EDIT: No, I was not disrespecting them before *cough* like axehandle *cough* (j/k j/k), it was an accident :P

[Edited on 24-2-2004 by Saerynide]
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[*] posted on 24-2-2004 at 02:09
Site updated.


NOW

The new page is under construction and there are some nice pictures *cough* *cough*.

http://species8472.dyndns.org/no2/no2_2.html


Quote:

But you really should treat your lungs with a bit more respect. I respect mine ALOT more now, after having gone through over a week of pain from HCl/Cl2 poisoning feeling like I continuously could not get enough air


I took the pictures with a window open. The smell of NO2 only allowed for 18 shots before I had to stop the reactor.... :o

I respect my lungs much more now, I have seen how much of a beating they can take without killing me. :)

Seriously though, I've implemented some new security protocols:

1) Window open.

2) No sniffing.

3) No tasting.

4) No electrocution.

Edit: 5) No drinking of HNO3, even if dilute.


[Edited on 2004-2-24 by axehandle]




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[*] posted on 24-2-2004 at 05:39


"Besides, human lungs can take a lot more than one would think"

axehandle you are without doubt a fucking idiot.

Its very easy to get blase about NO2. Familiarity breeds complacency, particually when you havnt read the safety data.

You can breathe in NO2 and feel as if youve got away with it, normal, undamaged. Then 8 hours later, up to a day or two, you can drop dead of pulmonary edema. At lesser doses NO2 does largely unnoticed but long term damage to the rather fragile lung tissue. This is not simply caused by the acid NO2 forms as it dissolves with water, its a very reactive free radical - also why its paramagnetic and dark brown.

10+ years ago when I did my arc chamber/nitric acid experiments I didnt know this. MSDS sheets were not just a few clicks away, the information in the good books from the 40's was pretty lax on safety. I assumed a little NO2 in the air was no really bad thing and was a bit surprised one day after an accidental exposure I contracted chronic pneumonia, and which lasted long enough to give me a a decent scare. I thought, ok, what must have happened is that 'little bit' of NO2 knocked out the immune system in my lungs and I got an infection. I was completely wrong. What happens is the NO2 does so much damage in the lungs that the immune system assumes you have a major infection. It brings out the full 'pneumonia arsenal' to combat an infection that doesnt exist and for damage that was done up to days earlier.

Unfortunatly, the human body hasnt evolved to judge how nasty lab chemicals are, and since we dont know better we assume that some minor irritation in the mucus lining is just that. What you actually experience are just symptoms and we rely on our badly adapted biology to be giving us symptoms related to the damage being done by the gas so we can judge risk properly.

The thing about people that taste chemicals or test for high voltages with their fingers or hang around neer lit fuses, when everything goes fine people say 'hes, crazy' 'he must be insane' and then grin, and when things go wrong they say 'Oh shit, that was unlucky' or 'he shouldnt have done that' when what they really mean in both cases is 'what a fucking idiot'.

While in the long run it makes no difference if you kill yourself or when, there will be a lot of other people reading this thread that will assume you know what you are talking about. If you adopt a lax attitude to NO2, they will assume this is acceptable. It isnt.

"I know why the arc "rises". That's high school physics. "
Maybe you would like to explain why you think it will cause the arc to contact more air then?
"Because the airflow through the reactor vessel is very slow, close to stand-still. Hence a moving arc will contact more of it in a given time. "

Aparently high school physics is letting you down. An arc is a low conductivity path through the air, its low conductivity becuase its hot and (partially) ionised which the current maintains. Hot air rises becuase its less dense than the surrounding air and when it rises it pulls the arc with it since this is the path of least resistance. The arc is rising with the air, not through it. Trimming the ladder until the arc does not break solves a lot of problems, and combined with a static vertical magnetic field should increase yeild substantially (particually concentration in air making it easier to produce better nitric).

"I AM going to "recycle" some of the NO2 by feedback. "
No, dont do this, it would be bad.
"Why?"

Air passing into the arc comes out with a concentration of nitrogen oxides that does not depend on the amount going in. Its wasted NO2. Aditionally people seem to get better results if the air going into the arc chamber is dry.

You might want to take heed from the death of a NST in jacobs ladder config particually.
"The company manufacturing this particular NST gave me their word that it would work in a jocob's ladder config."

Read the thread on roguesci. While it will certainly work, how long it will live is more the question. I came to the conclusion that the constant sparking might well be generating fast voltage spikes (eg from inductive kick) that degraded the insulation over time. Its also possible it simply overheated from the neer short current.


"I'm not intending to make explosives. I'm very afraid of explosives. I AM, however, very interested in rocket fuels."

There is not so much of a difference. What fuel/oxidiser are you planning to make with the nitric acid?

For the record, I do not have a 'problem' with your project. I hope it succeeds. You are quite entitled to tread your own path, make your own mistakes and we will learn from it either way. I will try to help, you can listen to my suggestions or not, if something is covered well elsewhere I do reserve the right to simply point you to it rather than type it all in myself. If you state as facts things I know to be wrong I do reserve the right to correct them and last but by no means least, if you tell people things are safe when they arnt, if you tell people something is doing less damage to them than they think - when you havnt read the information and very particually when it relates to NO2 - then I do reserve the right to call you a fucking idiot.
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[*] posted on 24-2-2004 at 08:55


Quote:

"Besides, human lungs can take a lot more than one would think"

axehandle you are without doubt a fucking idiot.


Can you spell "humor" and "irony"?

Quote:

Its very easy to get blase about NO2. Familiarity breeds complacency, particually when you havnt read the safety data.

You can breathe in NO2 and feel as if youve got away with it, normal, undamaged. Then 8 hours later, up to a day or two, you can drop dead of pulmonary edema. At lesser doses NO2 does largely unnoticed but long term damage to the rather fragile lung tissue. This is not simply caused by the acid NO2 forms as it dissolves with water, its a very reactive free radical - also why its paramagnetic and dark brown.


Well, I've read up on it now, after a very nice person warned me without calling me "a fucking idiot". Apparently it is much more dangerous than I previously thought. I know that now. I'm not senile yet.

You might want to save on you "fucking idiot"s's. People tend to stop reading what you write after you start the childish name-calling.

[...snip...]

Quote:

The thing about people that taste chemicals or test for high voltages with their fingers or hang around neer lit fuses, when everything goes fine people say 'hes, crazy' 'he must be insane' and then grin, and when things go wrong they say 'Oh shit, that was unlucky' or 'he shouldnt have done that' when what they really mean in both cases is 'what a fucking idiot'.


I don't test for high voltages with my fingers, nor do I use fuses at all. I always (fior my rocket engine tests) use electrical ignition with a very long cable hooked up to an apparatus with TWO safety switches.

Nor will I ever "taste test" nitric acid again. Have you heard about learning from one's mistakes?

Quote:

While in the long run it makes no difference if you kill yourself or when, there will be a lot of other people reading this thread that will assume you know what you are talking about. If you adopt a lax attitude to NO2, they will assume this is acceptable. It isnt.


It's not my responsibility what other people think. And my "lax" attitude is part of my humor, which you obviously don't get. You must be a very boring person, OR there's something wrong with my humor.

[...snip...]

Quote:

Aparently high school physics is letting you down. An arc is a low conductivity path through the air, its low conductivity becuase its hot and (partially) ionised which the current maintains. Hot air rises becuase its less dense than the surrounding air and when it rises it pulls the arc with it since this is the path of least resistance. The arc is rising with the air, not through it. Trimming the ladder until the arc does not break solves a lot of problems, and combined with a static vertical magnetic field should increase yeild substantially (particually concentration in air making it easier to produce better nitric).


That's why the air is pumped in TANGENTIALLY, so that the arc will contact more (turbulent) air than if it where intruduced AXIALLY (w.r.t. the ladder).

I have already discarded, dumped, ditched a static arc, since it would require electrode cooling.


Quote:

"I AM going to "recycle" some of the NO2 by feedback. "
No, dont do this, it would be bad.
"Why?"

Air passing into the arc comes out with a concentration of nitrogen oxides that does not depend on the amount going in. Its wasted NO2. Aditionally people seem to get better results if the air going into the arc chamber is dry.


Fine. Won't do it then. No problem. Actually, one less problem.

Quote:

You might want to take heed from the death of a NST in jacobs ladder config particually.
"The company manufacturing this particular NST gave me their word that it would work in a jocob's ladder config."

Read the thread on roguesci. While it will certainly work, how long it will live is more the question. I came to the conclusion that the constant sparking might well be generating fast voltage spikes (eg from inductive kick) that degraded the insulation over time. Its also possible it simply overheated from the neer short current.


Time will tell.

Quote:

"I'm not intending to make explosives. I'm very afraid of explosives. I AM, however, very interested in rocket fuels."

There is not so much of a difference. What fuel/oxidiser are you planning to make with the nitric acid?


There is a very large difference. Rocket fuels deflagrate, explosives detonate. I was planning on trying out NC to start with.

Quote:

For the record, I do not have a 'problem' with your project. I hope it succeeds. You are quite entitled to tread your own path, make your own mistakes and we will learn from it either way. I will try to help, you can listen to my suggestions or not, if something is covered well elsewhere I do reserve the right to simply point you to it rather than type it all in myself. If you state as facts things I know to be wrong I do reserve the right to correct them and last but by no means least, if you tell people things are safe when they arnt, if you tell people something is doing less damage to them than they think - when you havnt read the information and very particually when it relates to NO2 - then I do reserve the right to call you a fucking idiot.


Everyone states as fact things that are wrong. It's the listeners responsibility to determine the truth of the statements. I could state that it's safe to jump out a window --- that does not make my fault if someone tries it.

And if you care to point out exactly where I've stated that NO2 is absolutely harmless, I'll accept the ad hominem title "fucking idiot". Mostly because sometimes I'm an idiot, everyone are, but also because I have a girlfriend, which means I'm occasionally fucking.

Does you hardware not support the concept of irony? And why are you so fond of the expression "fucking idiot"? Is there something Mr. Freud would find interesting here?


[Edited on 2004-2-24 by axehandle]

[Edited on 2004-2-24 by axehandle]

[Edited on 2004-2-24 by axehandle]




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[*] posted on 24-2-2004 at 09:25
stop now, please


I am sure Marvin could come back with another point-by-point discussion of your post, just like you did of his. I will ask him (or anyone else) to refrain though, unless it is to discuss technical points such as the efficiency of various arc configurations, or to clarify health aspects of the problem (without any further insults or wounded defensiveness from any party).

This discussion board covers many potentially dangerous topics. Nobody likes a dead or damaged experimentalist, least of all the experimentalist. You can learn from experience, but learning from experience alone carries too high a price.

I appreciate that you have a sense of humor, but please refrain from making jokes about hazardous activities outside of Whimsy. It is very difficult to discern tone from a text-only medium, and far more lurking "guests" than registered members visit this site. They can't ask for clarification. I would say that anyone who imitates what they read on a web discussion board shouldn't be surprised if things go badly. However, I would like this to be a web discussion board of high quality that doesn't injure the curiously-imitative.




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[*] posted on 24-2-2004 at 09:30


I'll gladly stop. Wasn't me who started it anyway.....

I'll just go away and sulk for a while now.




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[*] posted on 24-2-2004 at 17:53
OSHA Gas Concentration Limits


I notice the following from MSDS:
NO2 5ppm
Cl2 1ppm
I2 0.1ppm

Why are the limits for chlorine and especially iodine so much lower than for nitrogen dioxide? Also, does anyone know whether limits in ppm (parts per million) are by volume? Or by weight? If by volume I can see why I2 would be so low given that it is a solid.

Most toxic gases have OSHA limits of 1ppm. If volume, this is 1ml/m^3. Now, I figure there is 75 m^3 in the room I do my experiments in. Thus I always try to keep any reaction small enough that a maximum of 75ml of gas would be produced in a "worst case" (i.e. it all goes into the room) scenario. Obviously this is not foolproof - the concentration may be higher nearby, or I may miscalculate - but at least my goal is to stay under 1ppm.
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[*] posted on 25-2-2004 at 02:12


"There is a very large difference. Rocket fuels deflagrate, explosives detonate. I was planning on trying out NC to start with."
Ever heard of DDT (deflagration-to-detonation transition)?
Fully-nitrated nitrocellulose undergoes DDT under ANY confinement (even if ignited in an open jar).
Additives (such as AN, for example) change that.
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[*] posted on 25-2-2004 at 02:45


Quote:
Originally posted by hodges
I notice the following from MSDS:
NO2 5ppm
Cl2 1ppm
I2 0.1ppm

Why are the limits for chlorine and especially iodine so much lower than for nitrogen dioxide? Also, does anyone know whether limits in ppm (parts per million) are by volume? Or by weight? If by volume I can see why I2 would be so low given that it is a solid.


Doesnt I2 sublime?

Im surprised that the limit for Cl2 is less than that of NO2. I thought NO2 was more harmful than Cl2....
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[*] posted on 25-2-2004 at 03:51


Quote:

"There is a very large difference. Rocket fuels deflagrate, explosives detonate. I was planning on trying out NC to start with."
Ever heard of DDT (deflagration-to-detonation transition)?
Fully-nitrated nitrocellulose undergoes DDT under ANY confinement (even if ignited in an open jar).
Additives (such as AN, for example) change that.


I know, but thanks for pointing it out. I was planning to construct an end-burner fuel grain consisting of nitrated sawdust or similar with some sort of binder+inhibitor; dextrine or something similar. I haven't given it much though really, it's far into the future.




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[*] posted on 25-2-2004 at 03:54


Quote:

Doesnt I2 sublime?

Im surprised that the limit for Cl2 is less than that of NO2. I thought NO2 was more harmful than Cl2....


The value for I2 is probably for very fine dust.

And the lower value for NO2 might be because (this is speculation) NO2 damage accumulates, whereas Cl2 damage does not? I know not.

It's quite interesting though. Pity I like animals too much to do some tests :o

Btw, I conduct my experiments in a room that's about 25 square meters with a roof height of approx. 2.8m. That gives 70 cubic meters. Now, if I only had a way to determine the production of NO2 in kg/s, I could do some serious calculations, but I'll have to estimate that by using the apparatus, recording the time, and titrating the product. Then I can (assuming 100% absorption) calculate the time to reach the safety limit in case of worst case scenario: Leak between reactor and buffer jar. Very interesting, this.

Whoha! Just found out a way to rig an alarm. The airflow should be constant throughout the system right? If it differs between the pump output and the hole-through-wall-outlet, then there's a leak! This should be possible to do in a not too complex way, perhaps using two units that average the pressure over discrete time periods, say 1 minute.... but now I'm ranting.

[Edited on 2004-2-25 by axehandle]




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[*] posted on 25-2-2004 at 05:29


Quote:
Originally posted by axehandle
Quote:

Doesnt I2 sublime?

Im surprised that the limit for Cl2 is less than that of NO2. I thought NO2 was more harmful than Cl2....


The value for I2 is probably for very fine dust.

And the lower value for NO2 might be because (this is speculation) NO2 damage accumulates, whereas Cl2 damage does not? I know not.


They gave NO2 a higher limit than Cl2, which would be saying that more NO2 can be tolerated than Cl2... which I do not understand. Btw, I read somewhere that Cl2 poisoning is also cumulative :o
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[*] posted on 25-2-2004 at 05:36


Quote:

They gave NO2 a higher limit than Cl2, which would be saying that more NO2 can be tolerated than Cl2... which I do not understand. Btw, I read somewhere that Cl2 poisoning is also cumulative


Ah, I typed "lower" when I should have typed "higher". I must have been thinking of the human body's tolerance. Cl2 also cumulative? Hmm, I don't know. This needs further research. I'm not a physician, nor an expertise in poisons....

FWIW, before I fully understood the peril of NO2 sniffing, I probably got a lungful over time, so to speak. Haven't dropped dead yet though, but I'll make damned sure I'm not exposed again....

[Edited on 2004-2-25 by axehandle]




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[*] posted on 25-2-2004 at 21:25


Iodine does sublime fairly readily so perhaps those levels are for the gaeous state.

At one time I worked in a paper pulp mill that used CaSO3 to digest wood. They made this on-site by burning sulfur to SO2. I used to have to occaisionally calibrate the operators' Orsat analysis equipment. They used this to measure the strength of their SO2 gas stream. It would almost gag me just being in the room where the operators worked 8 hr/day for decades. They claimed that they were quite healthy.

Elemental chlorine was also used there as a pulp bleach. Occaisionally there would be a gas leak. When I got a whiff of this I always turned right around and left the area. It amazes me that there were no alarms or warnings by management. It would probably be different today.
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[*] posted on 27-2-2004 at 04:57
Interesting setback / development


Seems that dehydrated gypsum is hygroscopic. No arc. I measured the resistance between the electrode connections. It was 2.62 kOhm.

So I said to myself: If I feed a high voltage high current through this overnight the water should evaporate.

Said and done. Connected to the 220V AC mains overnight. The resistance is now up to 3.06kOhm.

Now I'm running the reactor using the NST. The internal temperature is up to 49C so far, which could indicate either water evaporation or an arc. I won't test-sniff it this time though. I'm just going to let it run until all those pesky water molecules have been obliterated.

The NST is getting very hot. I don't know if that's normal. It's supposed to be short circuit protected. I'm going with the assumption that it's normal. Probably should fetch the fan just in case....

I can't find my book of constants, so now I'm going to google for the conductivity of air.

If all else fails, I'm not out of luck. There are two bolts protruding from the reactor, both immersed in the gypsum very close to the electrodes. If I heat those using a hot-plate or a propane burner, they should heat up the gypsum inside the vessel.....




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[*] posted on 27-2-2004 at 05:09


I suppose you can always go back to the old one.
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[*] posted on 27-2-2004 at 05:24


No way, no way. The new reactor has tormented me for two-three weeks now, and I'll never give up until it works.



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[*] posted on 27-2-2004 at 06:23


Hehehehe.. Stubborness is the way to success. I never give up on good ideas :D
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[*] posted on 27-2-2004 at 06:24


Come to think of it, I don't give up on bad ideas either....



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[*] posted on 27-2-2004 at 10:57


I would be bothered the plaster of paris would dehydrate during the arcing. Have you thought about using sparkplug feeds to the arc chamber?

Insulation (mainly the air gaps might not strictly handle the voltage but if you use 2 it might provide enough if the arc gap start is close enough together.
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[*] posted on 27-2-2004 at 11:43


I hope you mean Mohms, because if your insulation is down to 3 kohms, you sure have a problem.

Instead of plaster of paris think of
Dental casting investment. This is what dentists and artists use to make molds for casted metals.

Is one of my favorite materials, you mix with water like plaster of paris (sometimes with microsilica emultion), but when it hardens, it resist VERY high temperatures. It does not contract or expand much. I use it to make refractary pieces. Take a look at the heating unit in my "versatile glassware" thread, it´s made of it.

Anyway, once it is refractary, I suppose the heating will drive away all the water, leaving a dehydratated cement with high eletrical resistance.

I used to know the chemistry of its hardening. The word "phosphate" comes to my mind.

You can find it at any destist supply shop.

I sugest you do a little search on this material, since you may find many uses for it.
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[*] posted on 27-2-2004 at 17:46


We shall see. I think I have driven out almost all of the water now. Otherwise, I'll find an alternative "place-holder".



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axehandle
Free Radical
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Posts: 1065
Registered: 30-12-2003
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[*] posted on 1-3-2004 at 03:53
GAK


:mad: The gypsum method didn't work... the dehydrated gypsum is hygroscopic... so I tried clay (which cracked) (and has considerable shrinkage). For the moment, I'm a bit out of ideas. The dental filling thing seems promising, but I doubt I could get hold of any.

I think I'm going to make an experiment using bentonite mixed with distilled water. That little bugger shouldn't conduct much. But it's still clay, and hence a pain to work with.

This is SO frustrating. I know the design works, and then I have problems for a month keeping the electrodes in place. Time which could be used making nitric is wasted on waiting for clay to dry out etc.... :(




My PGP key, Fingerprint 5D96 E09E 365D 1867 2DF5 C2FE 4269 9C19 E079 CD35

\"Verbing nouns weirds the language!\"
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