krazypunk50
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Nitric Acid Distillation Chemical Cleanup
(if the answer to this question was already stated in an old topic, please delete this. I've looked all over and cannot find an answer)
Nitric acid distillation is an easy process once you get distillation glass. I thought so after the 3 or 4 times i tried it in my 24/40 glassware.
After these tries, though, I noticed a problem. My 1 liter RBF reaction vessel (after cleaning) had a layer of what I assume to be KHSO4 or K2SO4.
I've tried boiling water in it and pouring it out, but this still does not get rid of the tiny layer and so, this is my question: Is it possible to
get rid of this layer through chemical cleaning? i.e. something like pouring HCL acid or sulfuric acid or some type of reagent that I have to turn
this layer into a soluble after-product by means of chemical reaction and easily pour it out and wash with water. If there is, your help would be
greatly appreciated.
[Edited on 16-9-2010 by krazypunk50]
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crazyboy
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Hot water should get rid of it but if it doesn't I usually put some sand or dirt in there with water and shake it around. Either that or a large
bottle brush. Acids won't do anything if it is an ionic salt like potassium sulfate.
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Contrabasso
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Hot water from the tap and half an hour usually sees all the residue dissolved and pourable.
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cyanureeves
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 be careful and wait until it is dissolved completely before swishing
around.ive broke a flask before with the hard salt.
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hissingnoise
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| Quote: | | My 1 liter RBF reaction vessel (after cleaning) had a layer of what I assume to be KHSO4 or K2SO4. |
The insoluble residue in the flask might be due to calcium contamination of your KNO3. . .
It should brush out fairly easily - sand isn't something I'd put into a RBF because of the possibility of scratching.
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mr.crow
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I don't have any first hand experience, but you could try something like CLR or other scale removers. Seemed to work well in the commercials 
Double, double toil and trouble; Fire burn, and caldron bubble
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rrkss
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Try a little vinegar. Does a great job making things like this soluble.
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krazypunk50
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hissingnoise, if this is a calcium based contaminant, would it be a nitrate since it has gone through a synthesis in which FNA was produced? i dont
have a brush big enough to reach it so is there something i can do to remove it chemically? I do like the scale remover idea mr crow but i dont have
access to such a thing. but I have many misc. chemicals!
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hissingnoise
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I'm just guessing that you have a film of CaSO4 in the flask.
A thin-handled, stiff-bristled artist's brush (fan shaped) might work!
If it doesn't, just get some canvas, paint 'n stuff and you'll be several steps closer to getting your own nubile artist's model. . .
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crazyboy
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If the deposit is a calcium salt HCl should make quick work of it, calcium chloride is very water soluble.
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Jimbo Jones
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Just use ordinary vinegar.
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krazypunk50
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Neither hydrochloric acid nor acetic acid worked. And i also tried acetone and ethanol just in case but nothing went away. It looked wonderful once i
poured acetone into it like it took the layer away, but when it evaporated, the layer came back. Any thoughts?
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Jimbo Jones
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Did you heat the vinegar (yep, vinegar, not acetic acid) in your reaction vessel? 
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Chainhit222
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I had that problem too after HNO3 manufacture, I think I might have used NaOH, but I do not remember.
Oh, I remember now. Cut yourself a piece of brillo pad (or some other shit for scrubbing dishes) and put it inside the flask, then take a steel wire
and press the pad against the flask surface and scrub it. I used soap and warm water with the brillo pad.
I would still try NaOH, its easier then dicking around with a wire.
[Edited on 18-9-2010 by Chainhit222]
The practice of storing bottles of milk or beer in laboratory refrigerators is to be strongly condemned encouraged
-Vogels Textbook of Practical Organic Chemistry
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Magpie
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Yes, I've been wondering why no one has suggested an alcohol/NaOH solution.
The single most important condition for a successful synthesis is good mixing - Nicodem
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rrkss
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Another easy way is to take some table salt, pour it in and add some ice. Then shake it around. The Ice + Salt work like a mild abrasive.
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krazypunk50
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The last time i tried acetic acid (and i did use vinegar 5%) nothing happened but this time I boiled it. nothing happened, so I tried sodium
hydroxide. i poured some into my flask (i did not weigh the amount) and added water afterward. I noticed after a while that the layer dissipated but a
ring was left where the sodium hydroxide didnt touch. i also noted that there was a part of that ring that was cleaned. I assume that the acetic acid
had some part in this because I boiled it in the flask at an angle. whatever the acetic acid didnt touch was not cleaned by the NaOH hence the ring.
but anyways, my flask is clean!
[Edited on 19-9-2010 by krazypunk50]
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