Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Hal,

I (obviously) wasn’t aware of the properties of HCl…

If there’s no other (practical) way of reduction, I’ll have to find out if it’s possible to buy from a chemical outlet as an
individual here in California.

Thanks, and Regards,

Roger



From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of halamander
Sent: Monday, January 18, 2010 10:25 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: [Homebrew_PCBs] Re: Reducing concentration of HCl from 10% to 40%





Roger,
I think you will find that this is not a particularly effective technique. HCl in its native state at room temperature is a gas,
what you purchase is an aqueous solution of it. I think you will drive the HCl out of solution before you evaporate much of the
water, thus leaving yourself with a weaker soln.
Hal

--- In Homebrew_PCBs@yahoogroups.com <mailto:Homebrew_PCBs%40yahoogroups.com> , "Roger Blair" <Roger.Blair@...> wrote:
>
> I wish to prepare some HCl/H2O2 etchant, and I have 10% HCl. (10% HCl is $5 per gallon, but 40% HCl which is what I need is a lot
> more expensive)
>
> The solution as I see it is to reduce the 10% HCL solution to 40% concentration. I am thinking of using a Pyrex container on low
> temp lab hotplate (100�?) to �boil� off the H2O. (outdoors)
>
> Since I know next to nothing about chemistry, not to mention whether this technique would actually produce what I need, I would
like
> to get some input here.
>
> I have a general understanding of safety issues in handling chemicals, and wish to do this in a reasonably safe manner, BTW�
>
> (I will be working with no more than 10 to 20oz. of 10% solution at a time, to minimize any environmental impact to me, and the
> surroundings.)
>
> Any advice would be appreciated.
>
> Thanks,
>
> Roger
>
>
>
>
>
>
>
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>





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