Homebrew PCBs

Being safety concious is always good, but ffs you are not going to require
amputation from a drop of peroxide on your finger.  Whitened skin, some
stinging or in extreme cases some blistering perhaps


On Tue, Mar 12, 2013 at 7:51 PM, smilingcat90254
<smilingcat@...>wrote:

> **
>
>
> First of all, distilling hydrogen peroxide from pharmacy grade 3% VOLUME
> peroxide is relatively easy. I posted it some time ago and some one
> recently said it as well. It's by freezing and throwing away the ice that
> forms.
>
> **** safety ****
> You need to be extremely careful in handling this concentrated stuff. You
> can only reach about 40 some odd percent concentration by freezing. Still,
> its "dangerous". I've accidentally had few droplets hit my finger (Yes I
> should have been wearing my chemical gloves but I wasn't) and the skin
> where the droplet hit, the skin immediately turned white, chemical burn.
> Then the liquid penetrated into the dermis, layer of skin where there are
> blood vessels and nerves. And the painful stinging sensation from the
> peroxide burn was really intense. It was good that I had the sensation. Had
> it stopped, then it would have meant that my finger would have to been
> amputated...
>
> ****Another safety aspect of handling peroxide****
> DO NOT EXPOSE TO UV OR EVEN BLUISH LIGHT (florescent light, sunlight is a
> big NO NO).
>
> DO NOT LET IT COME IN CONTACT WITH ANY METAL ESPECIALLY IRON BASED
> MATERIAL. This includes all stainless steel. Iron act as a catalyst to
> decompose peroxide into oxygen and water.
>
> Store in clean dark brown bottle but it should not be so airtight
> that it can build up pressure. Countless number of explosions have
> happened because of this most famous is the accidental sinking of Russian
> super sub the Kursk.
>
> **** Side note ****
> do not confuse volume concentration such as 3% vol H2O2 with 3% H2O2. big
> difference. You can not get 90% H2O2 nor can you make it at home unless you
> know lot about chemistry and have the right equipment.
>
> Concentrating H2O2 by freezing is more than plenty good for your etching
> need!! Don't make it any more dangerous than need to be.
>
>  
>


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