method for processing sludge
- Thread starter mosfetta
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That is Metastannic acid.
You have been here since 2017 and do not know this yet?
How have you used the forum this time?
mera
precise work.
I boil one part nitric with three parts water with my whole PCBs.
I look at everything that can be dissolved and I find a white floury slime and sometimes frozen/floury.
How do I deal with this
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As I said it is Metastannic acid and its curse has been discussed so many times that I really do not want to repeat myself.
Search the forum, there must be thousands of posts regarding this!
It is what happen when Tin and Nitric meets.
I know the metastannic by reputation.
my problem was whether other material can be found among the metastannic
I know the metastannic by reputation.
my problem was whether other material can be found among the metastannic
Of course there can be, that is why we do not use Nitric when we have Tin present.
Have you not used the search function on the forum?
Next time you use HCl to dissolve the Tin first then you can use Nitric.
But it is cheaper to use HCl and air bubbling but it takes more time.
To fix the Metastannic issue you need to dry it and then roast it.
It will then be soluble in HCl.
Do your own research in the future so you learn.
And read Hokes book and the other links I gave you.
Just to add, not that we want you to do all your research alone,
but we want you to actively research the subjects on the forum, Hokes book and anywhere else.
We will of course be here and answer questions when something gets too hard.
Information is much better absorbed and processed this way, in our experience!
Where tin is involved HCl can be quicker in the long run. Where nitric may dissolve the material quickly, the filtering of metastannic is more time consuming. In the end often making the use of nitric slower for over all use. This is where knowing the exact content of your material pays off in time savings. It is also one of the reasons for researching deeply before attempting to process mixed materials. Small scale it may not matter much, but large scale, volume processing, it can become a nightmare.
