NaNO3 to NaNO2 problem

[wolfram]

About 40 g of melted NaNO3 was slowly added 100 g Pb powder (from sinkers). I thougt that this manner would be good, since it would increase the area of lead exposed to the NaNO3. Instead of forming an yellow salt, the salt formed was some orange-brown junk? What could this be? Isn´t PbO supposed to be yellow, could it be PbO2?  

Thanx for any help

[tripswitch]

If you simply heat NaNO3, it will melt and then at a certain temp (I forget what) will begin to release little bubbles of O2. If you just keep it at this temp. until bubbling ceases you will have relatively pure NaNO2 on cooling. You can check how complete the conversion was by weighing before and after and comparing the difference to the theoretical O2 weight loss.

[wolfram]

Sorry but I think this is one of the many myths you belive in when you have studied chemistry by reading books but not tried it for real.
NaNO3 melts according to my papers at 306,8 C and decomposes at 380 C. NaNO2 decomposes at 320. So at the temprature that you say that NaNO3 decomposes to NaNO2 if it does it it decomposes further and doesn´t stay in NaNO2 state.

I have now used the mighty TFSE and found this instead:

http://bcis.pacificu.edu/~polverone/muspratt1/c-834.html

, it states that:

KNO3 + 2C + heat ---> KNO2 + 2CO

So maybee one could use it for NaNO3 --> NaNO2 also..?

[hypo]

what you get is some red/brown Pb salt. that's ok.

> 100 g Pb powder (from sinkers)

oops! are you sure that it's Pb?
you know, like tinfoil isn't made from tin nowadays.  

if you "dissolve" some powder in hot conc H2SO4, what color do you get?

[hester18]

NaNO3 + Pb => NaNO2 + PbO
This is the reaction to turn sodium nitrate to sodium nitrite by releasing a single oxygen atom.
From
     Inorganic Chemistry
     T. M. Lowry © 1931
and
     Inorganic Chemical Preparations
     Erdmann & Dunlap © 1900
     courtesy of PolytheneSam

http://www.geocities.com/dritte123/NaNO2.html

This is a fairly indepth and dangerous preparation, the temperatures are very high and lead is toxic so beware if you plan to give it a go.
~Hester

[spectralmagic]

OK, maybe I'm missing something, but...

Doesn't KNO3 + 2C + heat == BOOM?

Certainly seems to work that way for blackpowder...

[hester18]

The reaction of KNO3 and Charcol (2C) in gunpowder is a similar reaction however while heating NaNO3 and introducing Pb in an open container you are only in danger of losing some hair and eyebrows if that makes anyone more comfortable. On a very large scale it would be very dangerous, i have used KNO3 before and i will tell you 20g ignited will fill your kitchen completely with smoke.
Just do it outside or under a flow hood just incase and have a nice thermometer  and possibly a fire extinguisher.
~Hester

[Antibody2]

sorry to be a pain but a few years ago endless bees triied converting NaNO3 -> NaNO2 (Ab2 included) we all wasted alot of time (and NaNO3) some destroyed their hotplates and glass with Xtreme temps, but no one was successful at anything other than a series of failed reactions. Some poor optimistic bastards even triied to use thier pretend NaNO2 in subsequent reactions that also failed miserably, carrying a small fortune in precursers down the toilet with them.

Not saying it is impossible, but definately rough love.

NaNO2 is cheap and unwatched, you can say its for meat preservative if anyone asks.

[hester18]

Yeah it is easier to buy, however you'd have to cure a lot of meat to account for a kilogram or so of it. Anyone with access to the worlds largest auction can get it.
15 USD per Kg or close to it
~Hester

[hester18]

In a perfect reaction just sodium nitrite (white) and lead monoxide (aka. lead oxide-yellow), however the brown and orange you see could be lead dioxide (lead oxide-brown) or more likely something called sodium plumbite (aka sodium plumbate (IV)) Na2O3Pb, which is brown/orange. This must be decomposed by carbon dioxide, see the synth posted before.
Also make sure you are using fairly old sinkers, the newer ones that I know of are made of all or part stainless steel or other non-oxidizable metal alloys. However seeing how you got it to turn colors you probably are using mostly lead.
~Hester

[wolfram]

WTF...PbO occurs in two diffrent forms yellow AND red!!!
I get surpriced every doing this subject...

[wolfram]

"Did this reaction:

NaNO3 + C ----> NaNO2 + CO

Powdered NaNO3 and stoichiometric amount of active charcoal dust was mixed and then melted. Mixture was black-grey coloured. When melted some bubbles evolved and then one spark(then I moved bit further and watched the fun part.) Huge blaze evolved from mixture. After reaction mixture colour was changed to pale yellow-white. There was only minimal amount of charcoal left. Seems a good produce for NaNO2"  -TrollchEmist-


-------------------------------------------------

Congratulations!!! 
Did you really set it on fire? How long did the fire last?
If you would have a good scale you could messure if the corect mass has become gas...
But you can instead buy a rat and check the effect. The LD dose for a human (75Kg) is about 3g. So for a 500 g rat it should be 3/150=0.02 g.

..no im joking but if would be nice to know if its the nitrite you have.

Wolfram

----------------------------------------------

"
Yes it blazed really furiously about 10s or something(it was beautiful flame(height about 30cm and bright).

here the calculations:

58g NaNO3 and about 8g C
that would make a 0,68mole reaction

then (after filtering) getting NaNO2 powder(very white with pale yellow) about 31g. that's little bit less than expected but some of the blazing mixture propably splashed away( there was amounts of that around heating place.


Then tested the pH of my 'product' in water and that was definitely base(pH paper)

The NaNO2 solution in water is weak base

Then I did little sulfuric acid test with my 'product' and NaNO3 side by side. (dropped little both of them into sulfuric acid) The 'product' evolved some gases(nitrogen oxides) while NaNO3 was still. After couple minutes 'product' was dissolved and NaNO3 was still.

Broked my thermometer so i haven't done melting point test.

'Product' is definitely NaNO2

This is unbelievable easy synthesis of NaNO2 "

TrollchEmist

[hester18]

The synthesis looks pretty good, a lot more realistic than the preparation with lead using extreme temps. However I think it might be hard to get a really good yield when burning it in the presents of carbon because NaNO3 burns by itself and produces different products
2NaNO₃ + Heat => Na₂O + N₂ + O₂
So when you do the reaction you are probably getting some Sodium Oxide, which makes sense with your pH test because sodium oxide reacts fairly violently when dissociating in water to make hydroxide ions.
I think this method had potential to be a good source of NaNO₂, just need to find the yield and know if its high enough to use for the next step.
~Hester

[Chromic]

If the pH is like 12-14, then you know you made Na2O (NaNO2 is a base, but a weak one).

Btw, is NaNO2 really that hard to find? What are people, hypothetically, going to use this chemical for?

[wolfram]

You could maybee tell me where to find it in Europe..

[hester18]

Well Sodium Nitrite is available on the worlds largest .com auction, thats all I will say. The chemical itself is often distributed from a canadien address and the shipping cost is a little bit but its reagent grade and you cant beat that. One must check auctions periodically as the items go fast and do not stay online very long, maybe for a more obvious reason.... anyway i just look for what I want on the *.com daily and sometimes you get lucky. I dont know of this commodity is available in europe...maybe...maybe not...or maybe just change in shipping cost, im not sure. But it is available.

As for the practical use of NaNO2 you can only really say its for meat preservation, maybe your making excessive amounts of beef jerky for the nuclear holocost that will be upon us.

As for its greater purpose.

GABA + NaNO2 =HCL=> NaCl + GBL + various compnds of N and O
(Gamma-Amino Butyric Acid) (Gamma-ButyroLactone)
GBL + NaOH ==> Na-GHB
~Hester

[Chromic]

I'm now pretty sure that this would be a hot topic for nitroethane production. Reacting an alkyl halide or alkyl sulfate with sodium nitrite produces nitroethane... and of course, the reason it's so desired is that with nitroethane one can turn benzaldehydes into amphetamines... michael addition of nitroethane to the benzaldehyde to form the phenyl-2-nitropropene, reduction and boom. If you're talking a substituted amine like DOB... you're need only a small amount of nitroethane... it's likely also worth searching after for just plain amphetamine.

I first thought GHB too--that's why I asked the question... no one would spend so much time converting NaNO3 to NaNO2 to be able to make GHB from GABA, they'd switch routes to the oxidation of THF first. Sorry for interrupting the thread. Thanks for the info though.

[Antibody2]

sodium nitrite is also used in the pseudonitrosite route to nitropropenes

[imp]

sorry to be a pain but a few years ago endless bees triied converting NaNO3 -> NaNO2 (Ab2 included) we all wasted alot of time (and NaNO3) some destroyed their hotplates and glass with Xtreme temps, but no one was successful at anything other than a series of failed reactions.

Really? Hmmm, SWIM accomplished it no problem using KNO3, it was very easy. Used the procedures outlined on Rhodium's with no problem whatsoever. The Pb turns orange as it is oxidized and bubbles of O2 are noted. SWIM used a stove at high heat (maybe you didn't heat it enough?). This was allowed to react for over an hour (it started smoking). The residue was then cooled, taken up in hot water, filtered, evaporated, and the unreacted KNO3 allowed to crystallize (KNO2 will never crystallize from solution). This was repeated until everything was boiled down to a light yellow flaky and very hygroscopic solid.

The filterate from the reaction was basic (pH ~9), and the KNO2 worked fine for a diazotization (although there was some lead impurities still in it). SWIM can't imagine what problems a bee might have with this synthesis, it's quite straight forward.

[xxxxx]

read an article where iron was used instead of lead. fe added slowly to molten nano3 (or was it kno3..forgot the temperature, too) oxidized to fe2o3 so 38g (5cc) iron would be used for one mole instead of 208g (19cc) lead. nano2 is easier to buy for certain, though (us$13/lb).