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garage chemist
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I meant solid NaNO2 with 20% HCl dropped on it, this way the HNO2 decomposes to NO and makes a brown cloud.
I have pure NaNO2 at hand, I'll test if I can make a blue solution of HNO2, because I think that a rather strong solution of NaNO2 is required for
this!
Another thing:
Magpie, it is possible that some soluble lead compounds have formed during the Pb reduction of the NaNO2. I have a preparation where this is mentioned
and the lead is removed with a special process.
To a solution of your substance add a solution of sodium sulfate, white insoluble PbSO4 will precipitate if there are lead compounds in it.
And the pH value says NOTHING about the identity and purity of your product! Every tiny contamination, like decomposition of the NaNO3 or NaNO2 with
loss of nitrogen (a bit of this always happens) can strongly raise the pH.
The color is also worthless as an indicator of purity. I have fertilizer grade NaNO3 that is yellowish when powdered and might be mistaken for NaNO2.
During the reduction of NaNO3 with lead, efficient stirring is of utmost imortance, as is strong heating. Some preparations call for lead powder, as
this gives a better reaction rate.
Purification of NaNO2 can be achieved by making some isopropyl nitrite with it (nitrate doesn't react here), isolating and purifying the ester and
saponifying it by refluxing with alcoholic NaOH solution. NaNO2 separates right out, as its solubility in alcohol is small (3g/100ml in anhydrous
ethanol).
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chemoleo
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Yes, putting some NaNO2 into 20%HCl shold work best, because of NOx evolution.
Having made some organic nitrite recently, the blue colour is evident by dripping HCl into NaNO2(aq), but at least in the presence alcohol it
disappears wihtin seconds. A faint blue hue should be seen right away, even at lower concentrations, and the smell is very NOx like.
Anyway, Magpie, I'd probably repeat the whole thing, but this time with a large excess of Pb!
GC- I like your alkylnitrite-based purification!
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Magpie
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Garage chemist I placed a spatula of NaNO2 in a small beaker and dropped one drop of 6N (20%) HCl on it. There was an immediate and strong reaction
giving a brown gas. A control test on NaNO3 gave no reaction. So I do indeed have NaNO2. The only question is of what purity.
I will test for Pb. I will also do more testing for HNO2 blue color and report back. Thanks to all for all the help. It really is an interesting
compound.
The single most important condition for a successful synthesis is good mixing - Nicodem
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chochu3
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I know that every one should know the following reaction:
Pb + KNO3 -> KNO2 + PbO
the reaction was done using 100 ml crucible, all reagents put inside and melted . Once it started to melt it was stirred then allowed to react one
more minute and after stirring it was covered with a lid. It was allowed to raect for five minutes until reaction was stopped. Some of the substance
was put into HCl acid and fumes of brown NO and NO2 was given off.
The next method I will try will be ammonium nitrate with spongy coppper to form ammoinuim nitrite.
heres a pic of the substance it was moslty yellow from lead oxide and some of the lead turned a redish color from over oxidation with air.
[Edited on 14-1-2006 by chochu3]
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woelen
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Quote: | Originally posted by chochu3
The next method I will try will be ammonium nitrate with spongy coppper to form ammoinuim nitrite. |
Forget about that, it will not work. Ammonium nitrite is very unstable and in the solid state it quickly decomposes to water and nitrogen gas. When
heated, I can even imagine that it decomposes very violently. In aqueous solution, NH4NO2 also is quite unstable. In previous posts it was pointed out
already that ammonium and nitrite ions react quantitatively to form N2 gas.
It might be that mixing KNO3 and Cu metal gives KNO2 and CuO, but that should be a matter of trying. Of course, there also will be side reactions and
you get Cu(2+) ions in your final product. Cu(2+) ions form a green complex with nitrite and I can imagine that it is hard to separate this, harder
than lead.
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chochu3
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yes woelen but if the nitrite is formed add sodium hydroxide to precipitate sodium nitrite.
Basset, H. and R. G. Durrant. 1922. J. Chem. Soc., 121, 2631
This is the original article where ammonium nitrate was reduced by spongy copper to ammonium nitrite. It should be done in the absence of air and
spongy copper as copper wire will not reduce the substance to the nitrite ion.
\"Abiding in the midst of ignorance, thinking themselves wise and learned, fools go aimlessly hither and thither, like blind led by the blind.\" -
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unionised
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I saw a reference today to spongy cadmium as a reductant for NO3- to NO2-
http://www.hc-sc.gc.ca/fn-an/res-rech/analy-meth/chem/lpfc-1...
Given the toxicity of Cd I'm not sure this is useful but it sugests that there may be other selective reductants that work well in solution.
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woelen
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Quote: | Originally posted by chochu3
yes woelen but if the nitrite is formed add sodium hydroxide to precipitate sodium nitrite.
Basset, H. and R. G. Durrant. 1922. J. Chem. Soc., 121, 2631
This is the original article where ammonium nitrate was reduced by spongy copper to ammonium nitrite. It should be done in the absence of air and
spongy copper as copper wire will not reduce the substance to the nitrite ion. |
Ah, that sounds interesting. I did not know this. I once tried the combination ammonium/nitrite and that does decompose quickly on heating, but under
the special conditions you mention, of course things may turn out different.
Even then, however, I think it will be quite hard to do this in practice, with materials, available for the general public. If you obtain any results,
I would be pleased if you post them here, just out of curiousity.
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It seems that there is an OTC way of reducing nitrate in solution
http://www.jce.divched.org/cgi-bin/JCE/jce-idx.pl?type=turn&...
Not sure it's a lot of use, perhaps best for purification of nitrite made by a more conventianal pathway.
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garage chemist
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Sounds interesting, but I doubt that the reduction to nitrite will be clean at higher concentrations. Reduction of nitrates mostly gives several
different products.
Also, the method introduces Zn ions into the solution. In neutral pH, Zn(OH)2 will be produced and stay in the reducing column, clogging it.
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guy
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Can KNO3 decomposotion be catalysed by MnO2 similarly to KClO3 decomposition?
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Aqua_Fortis_100%
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hello
I used to prepare some DDNP and works, but still never tried to CTMTNA or other nitrosamine synthesis...maybe in next holidays!
My nitrite is very impure (theses days i no have ..i need make more) , because is made from "purified" double nitrates(50% NaNO3 ,50% KNO3 with
sulfates ,carbonates and others impurities as coating,leaving the fertilizer looks as small pinkish "prills" from fertilizer called here "salitre do
chile , sal duplo de sódio e potássio") which i only "purified", withdrawning the coating by dissolution/filtration (the coating isn't soluble or
then weak soluble), and evaporation of filtrated liquid, leaving a white powder composed of KNO3 , NaNO3 and some impurities... but i no realized the
fractional crystalization because for my homemade chemistry, i think, is sufficient ... ![:D](./images/smilies/biggrin.gif)
well,aprox. 2 months ago i tried 4 methods :
conventional nitrate/Pb
heating nitrate alone
sugar/nitrate
Ca(OH)2/graphite/nitrate
i'm away from heating nitrate alone and Ca(OH)2 methods because all times which i tried ,i failled...
first the Pb/nitrate.. my favorite method for make nitrite at the moment..
using heat resistent gloves, put 25g of double nitrates in improvised crucible (a tomato can with wire support), then added 65g of lead (excess
caulated of aprox. 15g.. and this Pb is from fishing weights). heat on improvised alcohol burner and constantly stired with a old and useless spoon
by 1 hour... tired for the heat, wait the melt mix turns a "cake" and breaking this cake in pieces first with own spoon after with a clear hammer..
dissolved and washed this yellow/brown granules/powder in 2 portions of 150ml of hot water each , and then filtered this.. remains in filter white
powder of lead oxides and unreacted Pb in "drops" or balls formates.. evaporated the solution in a enameled iron pan, (when almost all of the liquid
evaporated the solution turned yellow INTENSE and i haved problems when drying the nitrites ...)... ready! my calculated theoretical yield was
20,1g of "double nitrites" , but i got aprox. 15g of crude product.. for me isn't to bad...
heating alone the nitrate is a very BAD method, because after which i just looked in some books and ,of course, web, the temperature needed for
decomposing nitrate into nitrite and O2, is almost the temp. to decomposing also the nitrite..but i'm not totally sure of this..maybe has any secret
in procedures.. ![:P](./images/smilies/tongue.gif)
i put 100g of pure expensive NaNO3 (from food store), in same improvised crucible and heating on same improvised alcohol burner by 90 minutes..BAH!
only some small bubbles in melt NaNO3 and no visible change of colour(stays white), but when i keep the white cake becomes solid and crushing small
pieces and put in HCl nothing happens!!!! what about?
the sugar/nitrate ,firts i observed which when i burned unmeasured nitrates/sucrose (for some smoke ..)in a metal can , after burns , stays in can
small amounts of yellow cake. i always asked me what is this.. then when i searched more for nitrites i looked in E&W ,some things and looked
the following comment in a topic created by kingspaz:
Quote: | I've always mixed a small amount of sugar with KNO3, without melting or even powdering them. The amount of sugar must be more then what is used for
cheap rocket fuel...
Then ignite. It won't exactly burn, it'll smoke alot, boil, and produce sparks and heat.
If it fails to sustain itself, use more sugar. If it ends up with alot of black crud, use less sugar.
It's crude, but it works, it's always done the job for me.
meselfs, E&W member... topic there
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so i to find the reason which turns yellow! the nitrite! actually i find which several reductible substances can forms nitrites if oxodized by
nitrates.. this info procced?
well, the fact was which i put some piece of the yellow cake after burn in a glass cup with common muriatic acid, then the piece instantly starts to
bubble and give brown/red gas! i think which is good method for amateurs as i, but should has a lot of impurities..(maybe oxalic acid, etc)..
finally, the Ca(OH)2/nitrate/graphite method...( also discussed in same topic by Polverone and kingspaz which tried also and have success with the synthesis..)
from the equation:
2NaNO3 + Ca(OH)2 + C ---> 2NaNO2 + CaCO3 + H2O
2 KNO3 + Ca(OH)2 + C ---> 2 KNO2 + CaCO3 + H2O ..(CaCO3 insoluble)
i tried 3 times, in similar attempts..
in all attemps i used same amounts:
60g of (Na,K)NO3 (excess) , 5g of graphite powder (bought in hardware store as lock lubrificant) (excess) and 20g of Ca(OH)2 (also from hardware
store in cheap 7Kg bags containig Mg(OH)2 and others impurities)..
i started putting the double nitrate in improvised crucible on burner and wait a while for melt the nitrates, then i added slowly the Ca(OH)2 (which
is difficult to handle in synthesis due the big volume of small amounts ,compared with the others substances used (C, (Na,K)NO3) ), then i put also
slowly the graphite and aparentlly released SMALL amounts of water vapour.... the BIG problem mine is with Ca(OH)2: when i add the Ca(OH)2 ,it make
the melted nitrates more hard to maintain in this state(more Ca(OH)2, more difficult to melt the mixture), and even on the burner it's becomes solid!!
what i must to modify??? maybe mixing first the Ca(OH)2 and graphite, but my afraid is which the nitrate oxodizes the graphite before reacting with
Ca(OH)2!!!(??) adding water!?!?
well, if i to get found a place which sell me diluted HNO3 , i will try the HNO3/starch/NaOH method... others interestings things which i wish try:
nitrate/NaOH/C method (the advantage which not has the problems of calcium hydroxide, but the disadvantage is which formed Na2SO4 should be quite hard
to remove by crystalization and reduces the nitrite yield ..)
--------
frogfrot , you tried to remove KNO2 from your Potassium dichromate synthesis ???
( just: Cr2O3 + 3KNO3 + 4KOH --> 2K2CrO4 + 3KNO2 + 2H2O ) is much hard separate acetates and the "other compounds in negligible
concentrations"(extracted from link) from KNO3 ???
Thanks....
[Editado em 2-1-2007 por Aqua_Fortis_100%]
[Editado em 2-1-2007 por Aqua_Fortis_100%]
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guy
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36g KNO3 mixed with 9.8g of sucrose and roughly mixed togther. This was put in an steel bowl and heated, and lots of H2O vapor came off and all
carbon reacted and gave a yellowish-greenish liquid which forms a yellow solid. About a gram of the solid gives a medium brown color but had a lot of
CO2 bubbling.
Conclusion: not a good way to make very good yields of nitrate. However the reaction is very fast (about 1 minute).
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obsessed_chemist
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Quote: | Originally posted by chochu3The next method I will try will be ammonium nitrate with spongy coppper to form ammoinuim nitrite.
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I have read that ammonium nitrite can be acheived by reacting hydrogen peroxide with ammonia. I will try to find the reference.
If the solutions were pre-chilled, and added slowly with much stirring, and tempature closely monitored, perhaps the yield would be decent. This could
then be reacted with sodium hydroxide to yield sodium nitrite and ammonium-water, which could be mostly boiled off, and then the sodium nitrite
solution chilled and mixed with alchol to precipitate it. Any thoughts?
[Edited on 3/23/2007 by obsessed_chemist]
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obsessed_chemist
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quick update; just as an experiement I tried slowly mixing portions of both room temperature household ammonia (3%) and hydrogen peroxide (3%). I
figured that the reaction stoichiometry is approximately a 1:2 ratio (for the solutions) of ammonia:peroxide, assuming that a reaction would proceed
as follows:
4NH4OH + 7H2O2 ---> 2NH3NO2 + 14H2O
No heat nor bubbling evolved, and it still smelled a bit like ammonia. Then again, most ammonium salts smell like ammonia, so a reaction could be
deceiving. Still, the ammonia scent lingered. My guess is that some gentle heating might be worth a try in the future. Or maybe bubbling gaseous
ammonia through an ice-bath chilled 30% peroxide solution would yield good results. But at that point, it would no longer be OTC.
On a seperate note, has anyone tried mixing NaNO3 and Pb powder in a ball mill, than shielding the reaction mixture with an inert gas like argon?
[Edited on 3/23/2007 by obsessed_chemist]
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Levi
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This patent claims to use peroxide to oxidize ammonia to hydroxylamine.
http://www.patentstorm.us/patents/5320819-description.html
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The closest I got to ammonium nitrite was attempting to recycle some ethanol / water containing ammonium nitrite as a by-product. This was at work and
the idea was to recover the solvent. On my first run I stopped the 1 L flask distillation with about 150 ml in the flask. When a bit of air got into
the flask the reaction started and the residue went like rocket fuel. I found out afterwards ammonium nitrite does not exist as a (stable) solid. The
couple of 45 gal drums containing the stuff was still stored at the back of the place when I left.
Closest I ever got to blowing my self up.
mick
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Filemon
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Do you know some nitrite salt that is insoluble in H2O? I know the Co(NO2)2. The Fe(NO2)3, Fe(NO2)2, Al(NO2)3, are they insoluble? Can somebody check
it?
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not_important
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Aluminium nitrite may not exist. Most simple nitrites are fairly soluble, the low solubilities seem to come with complex salts.
Cu(II) forms a low solubility complex nitrite, given variously as 2CuO . N2O3, and Cu(NO2)2 . 3Cu(OH)2
Mixed salts listed as slightly soluble to very slightly soluble include Ca(NO2)2.Ni(NO2)2.2KNO2 ; CaCuK2(NO2)6 ; CaNiK2(NO2)6 ; FePbK2(NO2)6,
NiPbK2(NO2)6.
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Filemon
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Quote: | Originally posted by Theoretic
nitrate. It should be reduced like so: 2NaNO3 + S => 2NaNO2 + SO2. SO2 should be led into Na2CO3 solution (not, NaOH, for reasons of greater
availability and lesser alkalinity, which could otherwise induce suckback). Na2SO3 thus formed could be reused for reduction.
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I have proven mixing Na2CO3 and KNO3 in H2O ammonia it has taken place, if it is not ammonia it looks like much. I toss sulfur and it didn't react, it
continued taking place ammonia. What reaction does it take place? Then, I proved with KNO3 and NaOH when I toss sulfur it reacted being dissolved in a
product red-orange. What substance is it? It is not K2SO4 neither K2SO3.
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guy
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Quote: | Originally posted by Filemon
Quote: | Originally posted by Theoretic
nitrate. It should be reduced like so: 2NaNO3 + S => 2NaNO2 + SO2. SO2 should be led into Na2CO3 solution (not, NaOH, for reasons of greater
availability and lesser alkalinity, which could otherwise induce suckback). Na2SO3 thus formed could be reused for reduction.
|
I have proven mixing Na2CO3 and KNO3 in H2O ammonia it has taken place, if it is not ammonia it looks like much. I toss sulfur and it didn't react, it
continued taking place ammonia. What reaction does it take place? Then, I proved with KNO3 and NaOH when I toss sulfur it reacted being dissolved in a
product red-orange. What substance is it? It is not K2SO4 neither K2SO3. |
Na2CO3 and KNO3 does not make NH3.
Sulfur dissolves in NaOH to make polysulfides which are usually red or yellow.
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Filemon
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Quote: | Originally posted by guy
Na2CO3 and KNO3 does not make NH3.
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I have also surprised. But smelled ammonia. You prove.
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Polverone
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Quote: | Originally posted by Filemon
Quote: | Originally posted by guy
Na2CO3 and KNO3 does not make NH3.
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I have also surprised. But smelled ammonia. You prove. |
I would guess that your KNO3 is impure and contains some ammonium salt. Do you smell ammonia if you mix it with a small amount of NaOH or KOH and add
a couple drops of water?
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Aqua_Fortis_100%
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chochu3 , i've tried similair procedure , but in a new batch...
600g of double saltpeter ("50% NaNO3 - 50% KNO3) plus about 1,3 Kg of lead fishing weights , heated in a paint can for several hours (heated by wood
) and well stirred over the time.
this gave very similair hard pieces that i havent still stracted.. many lead seemed to be unreacted, so as soon as possible i will add more lead and
remelt to see improvements in yields... i expect that this amount of nitrite last for many time...
these pieces seems to be extremely hard.. the clean hammer was my choice in early batchs..this allow better extraction with hot water
(the earlier batch , after purification, also gave a reddish cloud when added to muriatic acid , and also reacted with urea to gave , thought, some
nitrogen )
[Edited on 17-8-2007 by Aqua_Fortis_100%]
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kmno4
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I used to make about 500g pure NaNO2 by NaNO3/Pb reduction (about 10 runs, heh). It is "nice and easy" reaction but....
1. Always remains some unreacted Pb even if reaction lasts several hours and more than 1 mole of Pb per 1 mole of NaNO3 is used
2. Molten mixture has to be very often stirred.
3. Always remains some soluble Pb salts in extracted melt [Pb(NO2)2 or some NO2(-) complexes of Pb - I do not know - is intensively yellow-orange. Try
reaction, for example, Pb(NO3)2 and NaNO2 in water] and they should be removed.
4. Reaction yelds some Na2O (?) and extract has to be neutralised with dilute HNO3 [or CO2 gas] drop by drop. During carful neutralization, all Pb
precypitates as some bacis insoluble salts [or just Pb(OH)2] and in one step solution is neutralised and freed from Pb.
5. To prevent plaing with all mass of solidificated melt, it is much better to transfer it ,when still molten, on sheet of steel (or something like
that) by spoon, in a few portions and let to cool down.
6. Playing with Pb - it is not good and reaction leaves a lot of useless (or not, heh) Pb/PbO/Pb34O mixture. I still have it - few kilograms in a
glass jar.
Besides, there are a lot of books describing these procedures.
NaNO2 content is easy to determinate using KMnO4/H2SO4.
(add slowly [with stirring], NaNO2 solution to KMnO4/H2SO4 sol. untill it becomes colourless)
... but much better is to buy it (as I did later )
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