Refine gold by enriching the karat gold?

[Au79]

Hey!
I was wondering if anybody knew anything about a process which is to enrich the gold with like .999 fine gold to raise the karat to be aronund 21-22karat. Then use AR solution to dissolve the now enriched karat scrap . Then take it from there.

This would lead to use less nitric acid by a lot. HCl is so more convenient, cheap and not that toxic/corrosive and less waste?

Has anyone tried this metode? Any downside by using this metode?

The gold used to enrich the scrap gold could be gold you already have refined from a previously batch.

Best regards :G
- Herman

 

[nickvc]

The truth is about this method you would need an awful lot of fine gold to increase the karat of the scrap thus any savings you could possibly have made would be lost due to the large increase in the gold needing dissolving.
Sorry this isn’t a winning method, we normally use silver to inquart as it uses less nitric to dissolve it and the base metals, plus we can and do recover the silver because of its higher value and as a bonus any PGMs will also go into the nitric solution.

 

[goldenchild]

I've done it before. It's as up front and simple as it sounds. The problem with it is like nick said you need gold on hand to do it. I disagree with it not being a viable method though. If you're fortunate enough to keep a stock of gold on hand, that you don't have to sell like you would silver, then it's actually pretty awesome. Think about it. You keep a certain amount of silver on hand to keep inquarting. You can do the same with gold. As with silver OR gold you don't have to have a great quantity if you're willing to do small batches at a time. Each recovery gaining you even more gold for the next batch.

 

[FrugalRefiner]

Enriching gold content and inquartation both work. It depends on your feed material. If your feedstock is below around 10% or so in silver content, you can go straight to AR without either. If the silver is higher, and can form a crust of AgCl, then either inquartation and a nitric leach, or enriching gold content and going straight to AR can work. Which process to use depends on your feedstock, excess silver/gold you have on hand, price of nitric, etc.

Dave

 

[nickvc]

The op was talking about raising the karat level to 21-22 karat, now if you are working with 10 k then for every gram you have you have to add 6 grams of fine gold to reach 22 k.
If you have an alloy with 20% silver you need to more than double the weight with fine gold to allow it to dissolve which is fine if you are working with a few grams to maybe a couple of ounces but in big volume you are tying up a lot of gold which could be turned over to buy more scrap , not a viable commercial option when you are working on very small margins and very large volumes.