HAuCl4
Well-known member
4metals said:The thing that interests me about this is the ease of treating the waste acid. In a formic reduction a complex is formed which is a pain to break causing extra steps and specialty chemicals to clean up the acid.
When treating old sterling silver it is not uncommon to find 0.5 parts per thousand of gold in the silver. In this method the lack of filtration before adding the copper would leave the gold in with the silver. Also any palladium, which can also be in old sterling, will be in the silver as well.
What I think Hrushi meant by adding hydrochloric was testing a drop of the blue acid in water containing a few drops of hydrochloric. Any silver still in solution will turn a cloudy white. I do not think he is adding hydrochloric to the silver nitrate.
Check Hoke's description of procedures for cementing/cleaning up the silver chloride at the Homestake mine after Miller processing. At the end there is a pretty thorough description of getting the silver crystals cleaned up with ferric chloride and washing with HCl. Those crystals are about the dirtiest cemented silver that can be had as feed by man or beast. And yes, there will be some AgCl at the end to deal with. I didn't learn it from there, but from trial and error. :shock:
From the video it seems the bucket on his left has HCl and leaves a little white cloud when added to the blue liquid.
Boy, am I glad that is Hoke claiming 9995-9997 silver and not me... :lol: