alking - 29-12-2016 at 19:32
I have a common brand of sulphuric acid based drain cleaner. It's generally pretty clean, just a light tan/yellow color to it, but I want some clean
98%. Last time I vacuum distilled it and it was a pita because I just can't apply enough heat. If I'm doing 100 to maaaybe 200ml I can do it, but
beyond that it just sits there. So I tried to do the H2O2 cleanup, but to my surprise it's not working and I'm curious what is going on.
I add the H2O2, 35%, and stir with a little heat, ~80C or so. As you would expect it seems to clear up. I think there is just a tinge of color, but I
can't be sure, it's so faint. Adding more H2O2 doesn't seem to remove it so I figured it must be the lighting. I remove the stir bar and heat it up
outside to which it quickly turns yellow and it does not seem to dissipate over time.
I repeat the H2O2 trick until it becomes clear again, or clearish as before anyway, thinking I just didn't add enough. Back to try and boil it off and
it turns the same color/shade. It's getting cold outside so I stop the project for the day and as it cools I notice there are now suspended salts in
it which were previously not there (or dissolved anyway) and a lot, but not all, of the color fades as well. I really doubt I boiled the water off as
I never even got it to boil, just degas and fume, so that shouldn't have affected the solubility if any were present before. Any ideas what is going
on?
alking - 31-12-2016 at 12:12
Well no answers, but I've given up and am just distilling it with a bunson burner. I'm assuming these must be metal sulphates of some kind and that I
have no choice but to distill.
alking - 5-1-2017 at 09:15
I'd still like some help with this actually. I'm confused as these do not seem to be soluble in water but I don't know how. The only thing I can think
is that it must be a new compound created with the addition of the h2o2. I used some of this drain cleaner to make piranha solution to clean some
glasswear and now I have the white flakes stuck in it. It will not dissolve in water or hcl.
Sulaiman - 5-1-2017 at 10:35
I've not had enough confidence yet to go to boiling H2SO4 or Hg temperatures, so no help there.
As you are distilling, you will get the imputities left in the pot,
maybe a clue there ?
AngelEyes - 6-1-2017 at 06:51
Maybe filter it through activated charcoal?
I think that will remove a lot of the more solid and particulate crap, as well as any dye that may be in there.