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caterpillar
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What I know- may be, this info will be useful for someone. In my country there was no way to go and by perchlorates. I got Mg(ClO4)2, known as
"anhydron". One bottle I simple stole from an open shelf, the next was a present. I made NH4CLO4 and KClO4, and used them as oxidizers in solid rocket
propellant. But, one of my friends made chlorates. NaCl ->NaClO3->KClO3. It was rather simple, he used 300 Amps, graphite anod and steel katod.
250 gr NaCl + 5 gr Na2Cr2O7+ 5gr HCl per 1 liter. But, as I read, NaClO4 requires Pt anod. There is anlternative, really, PbO2 on graphite anod, But
in this case NaF must be added to solution of NaClO3 instead of bichromate and HCl. And chlorides must not present in perchloric cell. BTW: I read
about an explosion, that occured when one wise boy wanted to dry (CH3)3PO4 by mean of Mg(ClO4)2. Surely, he got some metylperchlorate.
Women are more perilous sometimes, than any hi explosive.
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dann2
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Hello,
If I add Barium Perchlorate (anhydrous solid) to concentrated Sulphuric acid will I end up with 100% Perchloric acid. The Barium will precipitate as
insoluble Barium Sulphate?
Barium Sulphate is insoluble in water but perhaps things are a bit more complicated in Sulphuric acid +/or Perchloric acid.
I suppose you could argue that 100% Perchloric acid is not a very wise goal.
Just wondering. Have Ba Perchlorate. Have conc H2SO4. The next step seems simple enough. I await further instruction.............
Dann2
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caterpillar
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DO NOT DO IT!!! Most likely you'll get explosion. Conc H2SO4 + salt of HClO4 produces not only conc HClO4, but Cl2O7 too. This compound can explode
after contact with trace amounts of reducing materials (and without serious reasons too). Ridiculous, but Mn2O7 has similar properties. Put some drops
of conc H2SO4 on KMnO4 and result will be similar as if salt of perchloric acid is used instead.
Women are more perilous sometimes, than any hi explosive.
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woelen
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Safer alternative is to dissolve Ba(ClO4)2 in water and slowly add 30% sulphuric acid to this solution. You get a precipitate of BaSO4 and after
filtration you end up with a solution of HClO4 in water. Before filtering I first would boil the liquid with precipitate of BaSO4. This makes the
precipitate somewhat coarser and easier to filter, but I still expect it to be a messy and slow procedure.
You can boil down the filtered solution safely. Put a thermometer in the liquid and boil away water until the temperature rises well above 100 C. Your
liquid then will be well over 50% of HClO4. Up to 70% concentration this acid is remarkably inert and you do not have to fear explosion or violent
decomposition.
You, however, have to very precisely adjust the amounts of barium perchlorate and sulphuric acid such that their stoichiometric ratio exactly matches
the reaction for formation of BaSO4. I think that for most practical purposes you can better have a slight excess of H2SO4 than an excess of
Ba(ClO4)2. Barium ions most likely are more disturbing than sulfate ions in most experiments with the acid.
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