YT2095
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Acetic + salt
I have/had a Litre of KBr and Acetic acid mix, the KBr is at 25% and the rest is 85% acetic acid with water to make up the rest of the litre.
I decided against heating and with air flow and an acetic scrubber, and decided to simply evap the bulk of it off in a shallow container in a
greenhouse (not in use).
I`m at the point where it`s starting to Crystalise now.
the "Plan" is to get the whole thing bone dry and then heat the crystals gently to drive off any excess acetic. and then redissolve in water and
filter off the KBr soln (there`s a few dead bugs in there). and then re-crystalise the KBr.
to ME this sounds acceptable for a crude KBr source, can anyone find fault or think of a better method?
ultimately I want to use this in a Bromate cell.
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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Nerro
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Why a bromate cell? You can also make Br2 using bleach and then add the bromine to a hot stirred solution of KOH.
Alternatively you could try to add something to the solution to force the KBr out of it faster. I'm thinking acetone for instance.
#261501 +(11351)- [X]
the \"bishop\" came to our church today
he was a fucken impostor
never once moved diagonally
courtesy of bash
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YT2095
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why wastse expensive chems doing what Nature will do for me for Nothing?
I`m not in any Rush or Hurry with this, I already have KBr at reagent grade 100g, I just want some really Nice (and ideal large and perfect Crystal
samples) the rest will get thrown into the cell to make the Oxidizer Bromate.
from there I can do what I wish with it, and so, is my method workable or are there problems I can`t see?
[Edited on 2-4-2007 by YT2095]
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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12AX7
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What kind of crystals does KBr make, anyway? I never got good crystals from NaCl or KCl, even drying slowly.
Evaporate to near dryness, rinse with H2O, then dry or recrystallize. Wash water contains some salt (how much depends on residue and solubility) so
can be fractionally crystallized to recover further.
Tim
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YT2095
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the sorts I get are flat and square the largest was 9mm and 2mm high.
but if you look closely they seem to be a series of concentric squares going down to a central point.
I only want a few so that I can mount them on slides.
happily there doesn`t seem to be any other junk in there, just the acetic and the bromide (and a few stupid insects now).
it was originaly a developer/starter for X-Ray plates, but the soln was "out of date" and couldn`t be used, so I aquired it.
\"In a world full of wonders mankind has managed to invent boredom\" - Death
Twinkies don\'t have a shelf life. They have a half-life! -Caine (a friend of mine)
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woelen
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If the liquid only contains KBr and acetic acid, then I would filter to get rid of the dead bugs, and then evaporate to almost dryness, simply by
heating. KBr does not decompose, so no need to worry.
Then redissolve again, and again heat to get rid of all water and small remains of acetic acid. This will yield sufficiently pure KBr (not nice
crystals, but some powder/crusts) for your bromate cell.
Nerro, I would not first make Br2 and then add that to KOH to make bromate:
1) As YT2095 says, why waste precious chems (esp. KOH, which is not that easy to get) for this, if it can be done without?
2) This is even more important. If you add Br2 to KOH, then for each mol of KBrO3 you get back 5 mols of KBr:
3Br2 + 6KOH ----> KBrO3 + 5KBr + 3H2O
Separating that KBrO3 from the large excess of KBr is fairly cumbersome, and you'll have big losses, etc.
Using a bromate cell (with a pinch of K2Cr2O7) gives KBrO3 and that does convert ALL of the KBr to KBrO3, not only 1/6 of it.
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