meatheadmerlin
Well-known member
I tried this method for a few reasons:
. I first found this idea presented as a means to etch circuit boards
for quick and cheap home-hobbyists fabrication of project boards,
and wanted to try to adapt it to recovery of precious metals.
Refining will come later.
. Vinegar, salt, and H2O2 (3% USP) are cheap and readily available.
In a pinch, you can even make vinegar yourself from waste sugar, juice, or wine.
And, I imagine you can use practically any soluble (read: Cl- ion producing) chloride salt,
although I have only tried various sources of sodium chloride so far.
I have used: table salt (can contain dextrose and be iodized, at times sourced from restaurant packets),
rock salt (for ice melting which can contain unknown mineral contaminants),
and canning/pickling salt (the closest I come to pure sodium chloride outside a lab-grade supplier).
I would imagine potassium chloride (a good portion of the content in sea salt),
and calcium chloride (also for ice melting and used for ice baths in ice cream making)
would also work just as well.
I would not recommend kosher salt (usually contains a sulfur compound, can vary by brand).
. I lack a well ventilated work area and have little protective gear currently.
Vinegar is safer to handle and does not evolve anywhere near as much chlorine gas during this use.
There are no major safety issues in storing vinegar, salt, or 3% hydrogen peroxide.
Also, just like regular AP, once you have a copper chloride solution,
there really is no need to use the peroxide to make new batches.
. Time to process is not an issue for me,
and I am less concerned about leaving this unattended for long periods of time.
. I have relatively small amounts of material to process at any given time,
usually small amounts of pins and gold-plated traces on small non-computer circuit boards.
(side note: breaking pins into smaller pieces through metal fatigue, not cutting,
to expose more base metal greatly improves reaction time.)
. I value the experience of experimentation with this new method.
And use this time to hone my lab safety skills before moving into more dangerous processes.
But, you are right. This is the long way around.
edit: added iodizing to table salt contents
. I first found this idea presented as a means to etch circuit boards
for quick and cheap home-hobbyists fabrication of project boards,
and wanted to try to adapt it to recovery of precious metals.
Refining will come later.
. Vinegar, salt, and H2O2 (3% USP) are cheap and readily available.
In a pinch, you can even make vinegar yourself from waste sugar, juice, or wine.
And, I imagine you can use practically any soluble (read: Cl- ion producing) chloride salt,
although I have only tried various sources of sodium chloride so far.
I have used: table salt (can contain dextrose and be iodized, at times sourced from restaurant packets),
rock salt (for ice melting which can contain unknown mineral contaminants),
and canning/pickling salt (the closest I come to pure sodium chloride outside a lab-grade supplier).
I would imagine potassium chloride (a good portion of the content in sea salt),
and calcium chloride (also for ice melting and used for ice baths in ice cream making)
would also work just as well.
I would not recommend kosher salt (usually contains a sulfur compound, can vary by brand).
. I lack a well ventilated work area and have little protective gear currently.
Vinegar is safer to handle and does not evolve anywhere near as much chlorine gas during this use.
There are no major safety issues in storing vinegar, salt, or 3% hydrogen peroxide.
Also, just like regular AP, once you have a copper chloride solution,
there really is no need to use the peroxide to make new batches.
. Time to process is not an issue for me,
and I am less concerned about leaving this unattended for long periods of time.
. I have relatively small amounts of material to process at any given time,
usually small amounts of pins and gold-plated traces on small non-computer circuit boards.
(side note: breaking pins into smaller pieces through metal fatigue, not cutting,
to expose more base metal greatly improves reaction time.)
. I value the experience of experimentation with this new method.
And use this time to hone my lab safety skills before moving into more dangerous processes.
But, you are right. This is the long way around.
edit: added iodizing to table salt contents
