Ba(ClO3)2
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Sodium Bromite
Reciently we have been very curious about bromites BrO2 (-).
In particular, sodium bromite NaBrO2. We haven't been able to find much information on these bromite salts.
However we have been able to find some information on sodium bromite.
The compound is stable and synthesizable. But there doesn't seem to be any information on how it can be made.
If anyone knows anything about bromites in general please share your knowledge.
We really are very curious about sodium bromite and would like to try making some. Does anyone know how It can be made?
Any help appreiciated.
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woelen
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Are you sure it can be made and stored? Do you have a source of that inco?
None of my books mentions bromite as a stable anion. Some mention it as an unstable intermediate in chemical reactions. As far as I know, the only
stable halite is chlorite. The latter is cheaply available as its sodium salt.
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Ba(ClO3)2
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Thanks for the response.
Sources
1. Wikipedia page on bromous acid mentions sodium bromite and barium bromite being stable and isolatable. https://en.m.wikipedia.org/wiki/Bromous_acid
2. Listed as a reagent supplied in aqueous solution http://onlinelibrary.wiley.com/doi/10.1002/047084289X.rs055/...
3. Describes how solid stabilized sodium bromite may be obtained from a solution http://www.google.com/patents/US4650658
We would perfer not to have NaOH in our product to stabilize it, so we'll aim to prepare a solution.
No. 3 lists NaOH, Cl2 and Br2 as starting materials and mentions a Japanese patent that gives the procedure. For some reason we can't find this
patent.
[Edited on 27-6-2016 by Ba(ClO3)2]
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Ba(ClO3)2
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We finally found something on the preparartion of bromites! https://www.google.com/patents/US3178262
It describes the preparation of strontium and barium bromites.
These salts are soluble and We're sure We could use them to make sodium bromite
Na2SO4 (aq) + Ba(BrO2)2 (aq) = 2 NaBrO2 (aq) + BaSO4 (s)
Besides having a sample, We also wanted to use bromites for a few things:
1. Making a stable solution of bromous acid
2. See if we can get some precipitates with bromite anions e.g Cu(BrO2)2, Cr(BrO2)3, Fe(BrO2)2
We now have the information we wanted. Sorry for creating this unnecessary thread
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woelen
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No need to apologize for creating this thread. Instead, keep us informed about your results. If you are capable of isolating NaBrO2 (or Ba(BrO2)2),
then that would be an interesting achievement and I certainly would like to read about that and may even try to reproduce the results. Reproduction is
one of the key elements of science. If others also are capable of getting your results, based on your descriptions, then you have achieved something
really useful.
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Ba(ClO3)2
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Thanks woelen!
We will certainly post are results. It will probably take a while before we're ready to present what we have found, but it will happen.
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j_sum1
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I love this kind of thread. They give me a chance to gain knowledge on things I hadn't even thought of.
Do post results of your findings. Preferably with pix.
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woelen
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The following may be an interesting read:
http://www.nrcresearchpress.com/doi/pdfplus/10.1139/v71-470
There also is a little book, containing a study on bromite and a description of how to isolate bromite:
https://books.google.nl/books/about/%C3%89tude_et_isolement_...
Maybe someone is able to find a scan of this little book?
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Ba(ClO3)2
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@J_sum1 we'll try our best.
@Woelen we have read most of the pdf you linked to. The book would certainly be a valuable resource. Thanks for the links.
Bromite esters might be interesting...
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clearly_not_atara
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This reagent turns out to be more stable than I thought. It decomposes at room temperature but it can be prepared by low-temperature oxidation of
bromide in alkali.
https://www.journal.csj.jp/doi/pdf/10.1246/cl.1980.671 (Kanagawa and Yamamoto 1980: bromite by electrolytic oxidation of Bu4NBr)
https://www.jstage.jst.go.jp/article/yukigoseikyokaishi1943/... (Okawara 1984: bromite by oxidation of Br- with Cl2 in NaOH sol'n)
It appears that the solubility varies significantly with temperature -- Wiley says 28% w/w at 0 C, :
https://onlinelibrary.wiley.com/doi/abs/10.1002/047084289X.r...
Cu2+, Fe3+, Ni2+, and Al3+ catalyze the decomposition of bromite in aqueous solution. Decomposition in presence of even a small amount of these ions
is rapid at 30 C.
Ogawara says that bromite is best produced at low temperature at a pH of 11-13. He states that it forms by the disproportionation of hypobromite.
I did not find any reports that use hypochlorite to produce bromite directly, or other oxidants besides chlorine. Still, it seems like it could be
possible. Engel et al say that the reaction of hypobromite with bromite (destroying bromite) is generally faster than the self-reaction of hypobromite
with itself (producing bromite), which explains why BrO2- is not so easily produced from the rxn of bromine and hydroxide:
https://pubs.acs.org/doi/pdf/10.1021/ja01636a092
Bromite is an efficient reagent for the Hoffman degradation and converts primary aliphatic alcohols to symmetric esters, including diols to lactones,
reactions which often give low yields by other methods. There was a flurry of Japanese research on sodium bromite in the '80s, after which interest
waned. It appears that propylene glycol may be converted to acetol:
https://www.journal.csj.jp/doi/abs/10.1246/cl.1994.53
Surprisingly, there is almost no report of potassium or caesium bromite.
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