On Sun, 18 Nov 2012 16:37:24 -0000, you wrote:
>Yes, keep in mind that the rocket backpack used in the 007 movie uses nothing but concentrated hydrogen peroxide. It hits a mesh of metal and instantly turns to H20, O2, and an incredible amount of heat.
The metal is platinum, IIRC.
Good reason to avoid using platinum tools when you make PC
boards......
Harvey
>
>Steve Greenfield AE7HD
>
>--- In Homebrew_PCBs@yahoogroups.com, "smilingcat90254" <smilingcat@...> wrote:
>>
>> You can purify 3% (drugstore grade of H2O2) by placing the H2O2 solution in a dark plastic bottle. No grease or other organic except the plastic and definitely not in a stainless steel or other steel vessel and FREEZE IT IN A DEEP FREEZER. When the solution has formed ice, remove the ice and the remaining liquid is concentrated H2O2. And you can use the concentrated H2O2 into your Acid bath without diluting the concentration of HCl (well not as much as if you had used 3% H2O2).
>>
>> Word of WARNING!! concentrated H2O2 can be very unstable so do NOT make a big batch! Make only what you need for the acid bath. Do not allow it to come in contact with oil, flesh, stainless steel. Steel act as a catalyst to decompose H2O2 in highly exothermic (heat producing) decomposition of H2O2 into water and oxygen. The reaction can runaway and cause the container to explode from too much pressure build up from oxygen generation. H2O2 does not explode chemically.
>>
>> Far as storage of acid bath with H2O2. keep it away from sunlight, halogen light or any light with blue and UV in it. Light will promote decomposition of H2O2.
>>
>> ---- on slightly different subject using vinegar ----
>>
>> Vinegar is acetic acid. Grocery store vinegar is only about 4% acetic acid. If you want to concentrate and use it for etching copper I think you can do this... To concentrate vinegar you can also freeze the vinegar and remove the ice. It's relatively easy to get 40% concentration of acetic acid if I remember correctly.
>>
>> Be safe!
>> Ms. Smilingcat
>>
>> Thank you for your note Mitch
>>