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Author: Subject: nitric acid preparation
food
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[*] posted on 29-4-2011 at 17:07
nitric acid preparation


General question regarding producing nitric acid by bubbling NO2 through chilled hydrogen peroxide. I followed the procedure as described in various places. Ok, mostly youtube. Combining about 32g of copper tube sections, 80g of 'ammonium nitrate' from cold packs, 50ml of tap water, and 100ml of muriatic acid in a 250ml vacuum flask and leading a tube from the flask barb to a chunk of glass pipette (seated in a wad of angel hair that I'd pushed into the cylinder base to help diffuse the gas) in about 35ml of 29% H2O2 in a graduated cylinder.


no2.jpg - 105kB

The reaction didn't 'do anything' right away; I'd been expecting a cloud of red fumes, so I slipped a container of hot water under the flask. After around an hour the flask was fizzing away quite vigorously and now a deep green. I wasn't seeing much action in the cylinder, the cylinder walls were clouding with condensate, the white background made evaluating what was going on difficult, but there was some fine buubles. Further down the road the fizzing had all but ceased. I decanted the green liquid, all that remained of the copper were some thing fingernails of copper, the liquid had no characteristics of the original HCl according to my nose.

Upon cooling and further chilling the green liquid I got two crops of nice green crystals.


xtal.jpg - 205kB

The resulting acid that I saw on the videos appeared much more concentrated than what I've obtained. And the crystals that I harvested don't look much like the CuCl2 crystals that I can find illustrations of. CuCl2 images that I've found all look like long needles and fine. If anyone else has tried this does it look par for the course?

have to run, tia




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Hades_Foundation
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[*] posted on 30-4-2011 at 13:10


You can get different crystals due to the conditions in which they were formed.
Crystal structure is the pattern in which the atoms or molecules are arranged, while the crystal habit is the visible form. You can get needles, platelets or other forms depending on the growth rate of the different surfaces.
http://en.wikipedia.org/wiki/Crystal_habit
http://en.wikipedia.org/wiki/Crystal_structure

As for the strength of the acid, I looked at a few of the videos, only the nurdrage one show a decent reaction when testing on copper.

Those youtube vids show an almost black mixture at the end. Sure your reaction finished completely?

Sorry I can't be more helpful, I'm only a beginner.
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[*] posted on 30-4-2011 at 20:20


Hey. Thanks for the input. I think that the reaction ran it's course. I'm curious to read that crystal stuff.

I did use more H2O2 than nurdrage did, about 50% more.

I've been reading about coordination complexes. That may explain what I'm seeing. It's interesting, and I'm not too disappointed. It's a bit of putting the cart before the horse, but now I have something to apply it to digesting the theory will be that much more palatable. Cheers!




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LanthanumK
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[*] posted on 20-5-2011 at 16:29


Did your cold pack state that it contained ammonium nitrate, or did you just guess?
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Rogeryermaw
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[*] posted on 22-5-2011 at 06:56


NH4NO3 and H2SO4 ammonium nitrate and sulfuric acid (conc.) distill mixture through an ice chilled condenser and chill the receiver as well. keeping things cold on the receiving side will help reduce oxides of nitrogen to give a fairly clean and highly concentrated product.

nitric.jpg - 60kB




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[*] posted on 22-5-2011 at 12:14


Quote: Originally posted by LanthanumK  
Did your cold pack state that it contained ammonium nitrate, or did you just guess?


did I just guess ? :)

not only did I read the contents of the package, but, skeptic that I am, I put some of the clean, white prills into a teaspoon with some water and a bit of NaOH. The smell of ammonia was there in short order. This fact and the printing on the label led me to the idea that there's a reasonable possibility that the product is actually ammonium nitrate. And I'm not being entirely sarcastic either; I'm talking, after all, about items from a dollar store, I could imagine mislabeling.

Quote: Originally posted by Rogeryermaw  
NH4NO3 and H2SO4 ammonium nitrate and sulfuric acid (conc.) distill mixture through an ice chilled condenser and chill the receiver as well. keeping things cold on the receiving side will help reduce oxides of nitrogen to give a fairly clean and highly concentrated product.


I may try that at some point. Was the yield decent? And is this fairly exothermic at the start?




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Rogeryermaw
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[*] posted on 22-5-2011 at 12:51


Quote: Originally posted by food  


I may try that at some point. Was the yield decent? And is this fairly exothermic at the start?


actually the process requires heating to drive off the HNO3. it also helps to insulate your distillation setup up to the condenser. the yield is fair and i could have gotten quite a bit more out of my distillation but i was outside, it was night, and i didn't want to leave the system unattended. if you plan to nitrate glycerin, WEAR GLOVES!!!!! i let the nitrated product touch my skin by accident and paid for it in the worst migraine i ever experienced.

http://en.wikipedia.org/wiki/Nitroglycerin#Side_effects




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[*] posted on 22-5-2011 at 17:26


Quote: Originally posted by Rogeryermaw  
if you plan to nitrate glycerin, WEAR GLOVES!!!!! i let the nitrated product touch my skin by accident and paid for it in the worst migraine i ever experienced.

http://en.wikipedia.org/wiki/Nitroglycerin#Side_effects


hmmmm "The side effects of nitroglycerin include lack of sexual desire, headache ..."

not tonight dear and I have a headache

that does sound unpleasant though, a good solid headache can really drain away the good times, that's for sure; I hadn't been aware that it could be a problem through absorption on the skin like that

I've been reading about that reaction, nitrating glycerin that is. Kind of on the want to try out list. I've been reviewing old threads here, the Davis book, and (brace yourselves) uncle fester, whose write-up seems to be in line with the other material. But no hurry for that.




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[*] posted on 28-5-2011 at 14:29


I did a small test run today using the H2SO4/KNO3 method in a 1:2 ratio respectively... Heated 10g KNO3 with 5g H2SO4 in a small glass retort, the end of which was all the way in the bottom of a 600ml beaker full of ice slush... This was heated over a Bunsen flame with a wire screen/asbestos in between, I held the heat until the mixture started to bubble, as soon as this happened I removed the flame and allowed it to boil lightly until it slowed, at which point I would repeat the heating to avoid producing nitric oxides at a higher temperatures. It was easy to see the nitric acid condensing, it Has a noticeably thicker or "oily" look to it and it wets the glass, eventually the distillate stopped being produced after about 15 minutes.

There wasn't much waste coming from the iced test tube where the acid collected, the end product is very clear and fumes heavily. it looks like that this gave me about 4-5 ml (meant to weigh the tube before and after but forgot, either way, this was just a rough test to see how worthwhile this method is..) It surely can be improved on, I'm wondering if I trickle fed H2SO4 at a very slow rate onto a larger quantity of KNO3 over lower heat would allow for more continuous production?

[Edited on 28-5-2011 by Mailinmypocket]
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[*] posted on 28-5-2011 at 15:06


Quote:
"The side effects of nitroglycerin include lack of sexual desire, headache ..."

Lack of sexual desire?
You obviously treated the 'wrong area' - again, it's; location, location, location . . .

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