rstar
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Preparation of Sodium persulfate
Hi Geeks,
Currently I don't have access to Na2S2O8.
Does anyone know how to synthesize it ???
I have a related compound Na2SO4  can i synthesize Na2S2O8 from it ???
"A tidy laboratory means a lazy chemist "
- Jöns Jacob Berzelius
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LanthanumK
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Electrolytic oxidation? Researching sodium persulfate on Google may help get the specifics.
hibernating...
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peach
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If it's just a persulphate you're after, ammonium persulphate is sold as "fine etch PCB crystals" at electronics stores.
There's got to be an electronics place in India that sells it.
The crystals are colourless, unlike the older FeCl3 etch crystals which are orange / brown nodules.
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Picric-A
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Potassium persulphate can easily be made from saturated solutions of potassium chloride and ammonium persulphate, the Kpersulfate ppt's right out.
Alternativly if your willing to spent a small fortune- electrolysis of sodium hydrogen sulphate (Na2SO4 + H2SO4) with platinum anode and lead cathode
will give a solution sodium persulfate.
K and Na persulphates perform exactly the same as ammonium persulphates
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AndersHoveland
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Would reacting sodium pyrosulfate with 30% hydrogen peroxide work?
Na2S2O7 + H2O2 --> NaSO5H + NaSO4H ???
Where the NaSO5H is sodium peroxymonosulfate, and the NaSO4H is sodium bisulfate.
Does not sodium peroxymonosulfate have essentially the same chemical reactivity as peroxodisulfate (Na2S2O8), since both are commonly referred to as
"persulfate" ?
I'm not saying let's go kill all the stupid people...I'm just saying lets remove all the warning labels and let the problem sort itself out.
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UnintentionalChaos
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Quote: Originally posted by AndersHoveland  |
Does not sodium peroxymonosulfate have essentially the same chemical reactivity as peroxodisulfate (Na2S2O8), since both are commonly referred to as
"persulfate" ? |
Not even close. UTFSE.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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AndersHoveland
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Would you care to explain the difference, or point us to a link, since I am having difficulty finding anything pertaining to the differences in
reactivity through such a search?
[Edited on 10-10-2011 by AndersHoveland]
I'm not saying let's go kill all the stupid people...I'm just saying lets remove all the warning labels and let the problem sort itself out.
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rstar
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Can this be possible :
Na2S2O7 + H2O2 = Na2S2O8 + H2O 
"A tidy laboratory means a lazy chemist "
- Jöns Jacob Berzelius
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rstar
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| Quote: Originally posted by Picric-A |
Alternativly if your willing to spent a small fortune- electrolysis of sodium hydrogen sulphate (Na2SO4 + H2SO4) with platinum anode and lead cathode
will give a solution sodium persulfate.
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Unfortunately I don't have any electrode that is made of Platinum, lead, gold, etc 
But I do have Carbon electrodes , will it work ??
"A tidy laboratory means a lazy chemist "
- Jöns Jacob Berzelius
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Picric-A
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No, the carbon will be oxidised to CO2 very quickly indeed.
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rstar
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How can it be possible ??
I used Carbon electrodes in making NaOH from NaCl in water, and
for making H2SO4 from CuSO4 in water. It didn't oxidize to CO2, but it did broke into small particles.
"A tidy laboratory means a lazy chemist "
- Jöns Jacob Berzelius
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ScienceSquirrel
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Ammonium, potassium, and sodium persulphates are readily available for etching PCB's.
You can buy half a kilo for a few pounds where I live.
It is unrestricted and as common as chips, I am sure that you can buy it in India
http://www.ebay.co.uk/sch/i.html?_nkw=persulphate&_sacat...
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peach
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I was moving all the bottles I have on the shelves and noticed my PCB etch is sodium persulphate, rather than ammonium.
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woelen
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@AndersHoveland: Sodium persulfate cannot be made from H2O2 and Na2S2O7 (or NaHSO4). Even stronger, H2O2 and S2O8(2-) ions react with each other, the
peroxide reacting as reductor and the peroxodisulfate acting as oxidizer. The products are bisulfate and oxygen.
A nice experiment which demonstrates that peroxodisulfate and peroxide are totally different is to add H2O2 to a precipitate of Ni(OH)2. Nothing
happens, the precipitate remains light green. If on the other hand peroxodisulfate is added to a precipitate of Ni(OH)2, then it turns black at once.
The resulting black compound is a strong oxidizer, capable even of oxidizing Mn(2+) to MnO4(-), albeit slowly. If H2O2 is added to the black compound,
then it quickly turns light green again, and oxygen is produced.
So, S2O8(2-) contains a peroxo-group, but it reacts very different from hydrogen peroxide.
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According to literature, peroxodisulfate can be made by electrolysis of ice cold concentrated bisulfate (e.g. the sodium salt) at very high current
density, using a platinum anode. At higher temperature or when another anode is used, then simply oxygen is produced at the anode.
[Edited on 11-4-12 by woelen]
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