nice offer and i would buy some if you are near me but i fear shipping would
be far more expensive then buying new.
but i have read the following:
degrading of H2O2 is less then 1% per year if stored in big tank or so. but
can get up to 2% in bottle etc. depends on stabilizer used. most H2O2 has some
sort of stabilizer added when sold (but not the one for medical use and not
the one for semiconductor manufacturer where purity is most important).
next week i will have a look at some shops who carry pool chemicals. on
several webpages i have seen H2O2 for pools, price is ok. i hope it is also
sold in shops here because it is mostly used in automatic dosaging units.
i also will check the car shops if this is clean sulphuric acid and if the
concentration is given.
but also if the sulphuric acid method has some advantages above the
hydrocloric (fallout of copper, more selective in agressing metals (can use
stainless)) i believe it would be more convenient for the amateur to use
hydrocloric because this also would allow him to bubble air instead of using
H2O2.
regards
st
19.04.2003 18:03:42, "twb8899" <
twb8899@...> wrote:
>I have a drum of food grade 35% hydrogen peroxide at my shop if
>anyone is interested. We could put it in gallon jugs for shipping but
>I'm not sure about UPS regulations on this material... it's pretty
>potent stuff. I'm open to ideas if anyone wants it.
>
>There is also a small chemical supplier near me who sells the
>peroxide in gallon jugs. I'll call him on Monday and see if he ships
>through UPS and post the details.
>
>Almost any grade of sulfuric can be used if the concentration is high
>enough. We used technical grade sulfuric which is 92.8% acid and
>about 1.8 specific gravity.
>
>Battery acid should work fine. Just pick up the container and if it
>feels about twice as heavy as the same amount of water then it will
>work. I saw a gallon jug of "sewer cleaner" the other day at a
>hardware store. When I picked it up to read the label I knew it had
>to be sulfuric because of the weight. Perhaps this could also be used.
>
>If anyone wants to test out this method just use the 3% drug store
>peroxide and some of this sulfuric sewer cleaner. The larger water
>content of the 3% peroxide can offset the 75% amount of water needed
>to make up the etchant. Just take two or three small bottles of 3%
>peroxide and add some sulfuric until it starts etching.
>
>This experiment should show how it works. No heater will be needed
>since the addition of acid will heat things up as it is exothermic.
>
>
>ADD THE ACID TO THE WEAK PEROXIDE SOLUTION IN THAT ORDER.
>
>WEAR SAFETY GLASSES !!!!!!
>
>Tom
>
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