Chemist514
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Cleaning up my sulfuric acid...
Just in case anyone has more info on this id thought id post something i found very interesting but is no doubt obvious and trivial to explain..
I am tired of my sulfuric acid being pink.. its not scary looking, it looks like kool-aid. I dont know its exact % as its Clear line drain opener but
it says its got sulfuric acid in it and has the same viscosity as the "real" sulfuric acid ive seen at work, only its pink.
In any case i was reading about activated charcoal filtering and thought, hell maybe this will take out the pink dye as its gotta be fairly inert dye,
you can mix it with sulfuric acid!
So i placed 25ml in a small flask to not quite cover some activated charcoal... it got warm. erm, ok fucking hot.. i put it in the sink in case it
popped the glass, there was small bubbling and the very faint scent of sulfer.. BUT it was almost clear! I added a small amount of water to see if it
was still concentrated sulfuric acid, as thats a bad thing to do.. it is indeed a bad thing to do, VERY exothermic, i put it back in the sink. lol.
any input?
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Baphomet
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The charcoal filtered the dye out but has reacted with the acid as well, by the sound of it. Otherwise the mixture would not have heated up. Sulphuric
is well known for attacking organic substances.
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Chemist514
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| Quote: | Originally posted by Baphomet
The charcoal filtered the dye out but has reacted with the acid as well, by the sound of it. Otherwise the mixture would not have heated up. Sulphuric
is well known for attacking organic substances. |
I was wondering about this so i added some more... less effects, i waited for it to return to room temp and added more, about 25ml at a time.. it
didnt do much of anything and is now pick again, so the clearing effect seems to be only with almost equal proportions.. perhaps my charcoal isnt fro
ma complete process so it does that sugar demo mech. leaving only carbon after... back to collecting chemicals...
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not_important
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Hot, concentrated H2SO4 can oxidise finely divided carbon to CO2, forming SO2 as well.
Alternative absorbants might be silica gel or absorbnt alumina, like is used for chromotography.
Another route is to warm the acid and slowly add small amounts of an oxidiser until the colour is gone. Persulfates work, leaving the sulfate as a
byproduct. Hydrogen peroxide works well but you must take care to only have a small amount in the acid at any point. I've had success with heating
the acid to about 100 C with stirring, and adding 15% H2O2 one drop at a time and waiting 20 - 30 seconds between drops. I was getting ride of trace
organics in the acid that gave it a yellow-brown colour.
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