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International Hazard
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Calcium nitrite 30% solution to inhibit steel rebar corrosion in concrete.
Attachment: eucon_bcn.pdf (135kB) This file has been downloaded 1473 times
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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Taoiseach
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Some interesting tidbits from "Chemistry - inorganic and organic" by Charles Loudon Bloxam (1883 lol ):
-solutions of nitrites are readily oxidized back to nitrate by heating in contact with air.
-sodium nitrate is reduced by fusion with iron fillings, the main product being sodium hyponitrite which can be obtained as
needle-shaped crystals
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roamingnome
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I was reading about the iron filling bit a few days ago,
but just looking at wiki for basic information
about Hyponitrite one finds ...
can act as a reducing agent for example reducing iodine, I2,:[2] N2O22− + 3I2 + 3H2O = [NO3]− +
[NO2]− + 6HI
that seems like a slick way to HI
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dann2
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Hello Folks,
Just wondering if I use roofing Lead + Na Nitrate for to make Na Nitrite, will the Tin (I don't know if there is/is not any) in the roofing Lead
interfere with the reaction or what products may I expect.
Thanks, Dann2
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DJF90
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Roofing lead should be pretty pure lead. Beware the "Adhesive flashing strips" though, as these are mostly bitumin with an aluminum foil; not lead as
I'm sure you could tell from that description. The brand name of these escapes me at this present moment in time.
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Taoiseach
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Tin/antimony is no problem at all as they get oxidized to white insoluble crap that is easy to remove by filtration.
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dann2
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Hello,
Attached patent describing seperation of Sodium Nitrite from Sodium Chloride. May be useful.
Dann2
Attachment: US3965247.pdf (284kB) This file has been downloaded 1051 times
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dann2
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Nitrate + Charcoal + Starch = Nitrite
Hello,
Link below states that you can make Sodium Nitrite from Nitrate, Charcoal and Starch.
http://chestofbooks.com/health/materia-medica-drugs/Manual-P...
Anyone tried this? I don't see it mentioned in the thread.
The Sodium Nitrite that I made from Nitrate heated with molten Lead appears to be only approx. 10 to 20% Nitrite. It does not really matter to me
actually, just saying.
I measured its 'purity' using a Nitrite detector kit for aquariums.
I had not realized you are supposed to fuse (melt) the Sodium Nitrate when mixing/stirring with the melted Lead.
Shall have to fire up the cauldron again........
Will Methylene blue detect Nitrite?
Cheers,
Dann2
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Taoiseach
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Another idea for the preparation of nitrites:
Calcium formate, Ca(HCOO)2, could be an excellent reducing agent for nitrates:
Ca(HCOO)2 ---> Ca(2+) + 2CO2 + 2H(+) + 4e(-)
2[NO3(-) + 2e(-) ---> NO2(-) + O(2-)]
thus:
2NaNO3 + Ca(HCOO)2 ---> 2NaNO2 + H2O + CO2 + CaCO3
the only products being calcium carbonate, sodium nitrite and carbon dioxide. The latter is a gas and calcium carbonate is one of the least soluble
calcium compounds (much less soluble than calcium sulfate even) - hence separation of the nitrite should be a breeze
I dont know if this reaction proceeds with reasonable speed in aequous solution but it'd be worth a try! Calcium format is quite soluble (6.6 g/100 mL
@20°C) and the slightest amount of carbonate produced would cause turbidity, thus showing that the reaction proceeds.
Under more vigorous conditions the reaction would certainly proceed, as formates make quite energetic fuels in oxidizer-fuel kind of mixtures. Maybe
by carefully adding Ca(HCOO)2 to molten nitrate in small(!) portions the temperature could be controlled not to exceed the decomposition point of
NaNO2 (271 °C).
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Taoiseach
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Looks like I'm talking to myself again
Reduction of nitrate to nitrite by formate is confirmed by attached paper. According to this, melted nitrate reacts vigorously with formate, evolving
carbon dioxide and turning from colorless to yellow. Apart from the reaction I suggested above, another competing reaction is reported to take place.
In case of calcium formate:
Ca(COOH)2 + 2NaNO2 ---> CaCO3 + Na2CO3 + N2O + H2O
This reaction would contaminate the nitrite with carbonate but the paper suggests its neglible.
Another problem mentioned is that the fused mass tends to suddenly explode
Adding Ca(OH)2 to dilute the mixture as well as to precipate any carbonate formed might remedy the situation.
No useful information could be found on the reduction potential of formate in aequous solution. There's a little chance it'd work tough. At least
sodium chlorate is known to be able to oxidize carbon in hot solution.
Attachment: Reactions between sodium carboxylic acid salts and molten sodium nitrate and sodium nitrite.pdf (925kB) This file has been downloaded 1359 times
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Taoiseach
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"Absorption of nitrous gases" (p.315), available from the library section, confirms the calcium formate route, stating that it quantitatively reduces
sodium nitrate to nitrite. Details are in French pat 388,563 which I was unable to find tough.
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Jimmymajesty
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It has not been mentioned before IIRC so I decided to post this method, as it seems the easiest method to make pure N2O3 to me.
Excerpt from brauer preparative inorganic chemistry page:488
NOHSO4 made by generating SO2 by potassium metabisulphite (OTC) + HCl and lead it into ccHNO3
SO2+HNO3=>NOHSO4
Then add water dropwise into the slurry to form N2O3 in a slow way.
I am not sure if it works, but will definitely try.
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Nicodem
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You probably mistyped it or something as it is right where it is supposed to be: FR388563 (also available in German version as DE203751)
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JohnWW
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When one tries to save PDFs of those French and German patents of 1908, v3.espace.com throws up popup windows that immediately cause Firefox to crash.
Has anyone been able to download them, somehow? If so, please post them here are attached files.
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Jimmymajesty
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I tried out the method for N2O3 generation by means of NOHSO4.
Unfortunately the SO2 reacts very slowly with icecold HNO3, and dry SO2 generation by K2S2O5 is a pain...
While bubbled SO2 through HNO3 I also made some K2S2O5 solution, it had a smell of SO2, so I poured diluted HNO3 on it and had a lot of (I presume)
N2O3 generated which dissociated at the heat of the reaction to NO and NO2..
Next time I will put K2S2O5 in a gas generator and drip HNO3 it and lead the gases into NaOH sol.
Would anyone be so kind to back me up that the following equation is correct: (I did not bother balancing it)
K2S2O5+HNO3+H2O=>K2SO4+HNO2+H2SO4
Thanks a lot!
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starman
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Jimmy I don't know your intended use of N2O3 or whether you're just interested in the chemistry of the route you're looking at.
Calcium nitrite solution quoted,available fairly cheap commercially(a hardware stare ordered in for me) plus dilute HCl worked very well for my
purposes.You get that lovely nitrous acid blue immediately on addition.
[Edited on 14-3-2010 by starman]
Chemistry- The journey from the end of physics to the beginning of life.(starman)
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Jimmymajesty
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Actually I don't know what to do with it at the moment but it is an interesting chemical, so I decided to make some. The calcium nitrite is not
available in my country, maybe only for some industrial bastards, sulfuric acid based drain opener also unknown.
The problem is I don't want to use lead as it is poisonous and also I have not succed in any thermal method to make it eg:sulphites+nitrates,
sugar+nitrates.
I have only made NaNO2 by starch + HNO3 so far, but a lot of NaOH ended up as Na2CO3 as a result of the evolving CO2.
I carried out a test yesterday as follows:
200g K2S2O5 was put in a flask and HNO3(85°%) were being dripped to it until no gas evolution was observed.
The problem was that owing to the heat generated by the oxidation, the formed SO2 and HNO3(gas) reacted in the condenser forming a solid mass possibly
NOHSO4 and something else that color was deep green. (I also get that green color when added H2O to the NOHSO4+HNO3, I don't know offhand what is this
material.. I am too tired to look it up )
I am going to repeat the reaction but, saturated K2S2O5 solution will be dripped into ~50% HNO3.
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starman
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Jimmy you seem to be making more complicated than necessary.You know that dilute HNO3 + Fe will do the job right? Sure your NO/NO2 ratios will change
later on slowly evolving excess NO in the end,but if its just to look and see,whats it matter?
Chemistry- The journey from the end of physics to the beginning of life.(starman)
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bluetrain
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I made sodium nitrate from ammonium nitrate and sodium hydroxide. A solution of the salt had a pH of ~5-6 which I guess means there still is some
ammonium ions in there. Would this be unsafe to melt? It will decompose at around 210'C into oxides of nitrogen and water so if I use a large enough
container I think I'll be safe. Impure ammonium nitrate can however explode when heated so I'm not quite sure.
Also, does anyone know if airgun bullets are pure lead or if there is added some other metal to make them harder? The lead I can source is from lead
batteries or fishing weights with the latter being the easiest to acquire. The stores are closed until Monday so if I want some nitrite this weekend
I'll have to use airgun bullets.
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Anders Hoveland
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Would NaNO3 mixed with HCl solution, and then adding aluminum foil, make nitrogen dioxide and nitric oxide?
I have see somewhere that Zinc with HCl can reduce nitrobenzene to analine so I would think it could reduce a nitrate. The nitrite would immediately
react with HCl, giving off nitrogen oxides.
NaNO2 + 2HCl --> 2NaCl + H2O + NO + NO2
The NO and NO2 could be bubbled into baking soda solution to make sodium nitrite.
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Polverone
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Quote: Originally posted by Anders Hoveland | Would NaNO3 mixed with HCl solution, and then adding aluminum foil, make nitrogen dioxide and nitric oxide?
I have see somewhere that Zinc with HCl can reduce nitrobenzene to analine so I would think it could reduce a nitrate. The nitrite would immediately
react with HCl, giving off nitrogen oxides.
NaNO2 + 2HCl --> 2NaCl + H2O + NO + NO2
The NO and NO2 could be bubbled into baking soda solution to make sodium nitrite. |
Why don't you try it? None of the needed materials are rare or expensive. I know that a mixture of hydrochloric acid and nitrate salts gives red
nitrous fumes with zinc.
PGP Key and corresponding e-mail address
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turd
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This thread shows that there are many ways to obtain nitrites. The challenge is to make *pure* nitrite. So far this thread didn't provide convincing
results (I might have missed something though).
The proposed N2O3 method does not seem to be advantageous:
http://www.erowid.org/archive/rhodium/chemistry/pseudonitros...
(Read the part about generating N2O3 from metals)
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Sedit
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Whats so hard and impure about the molten Lead method? if you have concerns of Pb contamination there have been suggestions of feeding C2 into the
solution and filtering off Pb carbonate other then that I find the Pb method easy and top not but a tad tedious due to alot of filtering and waiting
for the cake to dissolve.
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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turd
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Like I posted upthread: I tried with different metals and never got anything close to pure NaNO2. There was always more or less (typically ~50%) NaNO3
and other impurities. Particularly, I found the Pb method hard to control with either incomplete reaction or runaways. Maybe I'm just too clumsy for
this kind of chemistry, but it certainly isn't *easy* to get good yields with molten NaNO3/metal. Maybe one day I will try in vacuum and with an
excess of a metal that doesn't melt. But it doesn't have a hight priority since I managed to acquired some NaNO2 p.A..
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Sedit
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Its very easy esp when reducing NaNO3. KNO3 is abit harder.
Take a LARGE amount of lead and melt it. Once its melted completely start adding gram quantities of nitrate and stir. Keep adding till complete
addition and the stir as much as you can giving ample time for the reaction to finish. KNO3 is a bit harder because it likes to clump up with the
Litharge but all thats needed is extra heat.
Once you feel its done stop stirring cover loosely and let it set so that your nitrite and litharge float to the top. THEN turn off the heat
Cover and allow to cool.(This I feel is many peoples downfall is they allow reoxidation).
Add excess cold water and cover again and allow the cake to break up. The nitrite is highly soluble in H2O. Filter and filter again to remove litharge
and slowly evaporate or do so rapidly under inert atmosphere or positive pressre of steam. When its concentrated Allow it to cool and placeit in the
freezer where any unreacted nitrate will preciptate out. Filter and your remaining liquid is a concentrated Nitrite solution of purity I hav never
seen a problem with. The only issue I hae ever had is keepin the nitrite dry.
Its not hard at all just a process that sounds more complicated on paper then it really is.
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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