Hmmm - OK - I got a couple PMs asking for help from Gold.refinery as well
I basically told him he would best served posting here on the open forum
Gold.refinery - you need to keep all your questions in one thread - also the replies you are getting from member are some of our very best & highly respected members - So you need to keep your questions focused (in one thread) so that we can give you better/focused answers --- instead of questions/answers scattered all over
Original post, which is now apparently deleted
Here is one of the PMs I got which was ether a copy of his (now deleted) OP in this thread &/or very close so I am going to post that here in the hope we can get him back on track - it's a long post
Kurt
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Hello
I set up a refining system, but I have little experience. To know if I was on the right track, I wanted to report one of Refine operations.
Please help me about losing gold in this operation.
We performed refining operation using the AR method. Our input was 2610 grams; Analysis includes: 765 gold, 68 silver, 148 copper, 8 zinc, 4 nickel, 6 cadmium and some others.
We calculated the acid values to digest 7.5 ounces per liter of solution. Hydrochloric acid 32%, 9.3 liters and 2.3 liters of nitric acid 64%. We flaked the gold as much as possible. Then we poured it in Tumblr.
We added 7 liters of hydrochloric acid along with 1.3 liter of nitric acid.
We also added some hydrogen peroxide during the slow reaction. After one hour, the reaction was somewhat balanced, we added 3.5 liters of hydrochloric acid again and slowly we added 1.1 liters of nitric acid.
After four hours, the reaction was very low. I added about one kilogram of 46% white urea to neutralize nitric. About Urea , I have little experience with urea. I added until the bubbles on the surface of the solution diminished. I added a little water. Then I did not see a quick reaction by adding urea.
After a while, I added 12 liters of 4 C cold water. We waited for a while, then filtered the solution, left the silver chloride, and transferred the solution with water until the transfer path became clear. At the end of the Tumbler wash we had 111.38 gr unresolved gold.
In the case of solid gold residue, I did not notice washing it with ammonia. Because they were not covered with anything. I first tested them with XRF and then melted them, their assay was 771 Au.
I Approximately 1.8 liters of 55% hydrazine is dissolved in 2.2 liters of water and Slowly add to solution in half an hour.
Add the flocculate , leave the solution for 12 hours.
The liquid became green and clear, we filtered the liquid into a secondary tank(with Fabric polypropylene), took all the pure gold. Then we washed the gold powder with hot water. Then we dried the gold powder in a steel container.
We filtered the solution with two polypropylene cloth filters. We did not use a paper filter, of course I like the paper filter because it does not absorb. We took more than 98% of the solid particles from the first fabric filter and the rest from the second filter. We thoroughly washed the filters. Some gold precipitated, we took it and sent the remaining liquid to the second tank.
Stannous test, when the gold was sitting on the bottom of the solution, I tested the solution on top of that gold. The answer was negative.
Unfortunately, after filtering the solution, I did not try again.
Also, all the water has been added to them while washing, now it may be close to 200 liters.
I added some aluminum to the solution and mixed it and let people do it.
I need to learn more about Stannous testing, it's very important. I have never had a positive Stannous test.
After melting and XRF test, the purity of gold was 999.6 Au and it was shown in the analysis 0.4 cu cu and no silver Ag. (But it seems not enough washing) because the surface of gold bullion was not best quality, Their surface is star-shaped impurities.
We dried the gold powder in a steel container, then melted it in an induction furnace with a new plant.
After accounting, we do not have
12.6 grams of gold. I'm surprised, all the steps went well, no errors, and I'm sure of the scrap analysis. There may be some during the initial dubbing and gold powder, but we were careful and definitely not a lot. We have two places still left, silver chloride, the second bunker deposit.
I added two sheets of
aluminum to the second bunker.
Then we mixed well every few hours. We added flocculate and left for another day.
we filtered the place, the amount of jelly powder had accumulated on the bottom of the bunker.
We took it and heated it in a steel pan and it was almost dry.
We tested with XRF. Showed
30/1000 gold.
We transferred the rest of the solution to the third bunker and added the aluminum again.
So far, 12.6 grams of that lost gold, 3.6 grams in the second bunker have been deposited in the sludge, so our lost gold is about 9 grams.
How to get the gold in this purple powder?
My friend told me ,that powder put in reactor for next part refining. Is it ok?
So far there is some gold in silver chloride and maybe in the third bunker solution.
Dried silver chloride is about
170 grams, but I know the silver get is much less, right?
XRF testing of silver chloride showed that
98/1000 of it contained gold.
In the third bunker, after filtering, sludge containing 2/1000 gold was taken.(Almost very little)
Here I want the best way to recover the silver chloride to get the gold trapped in it and recover the silver.
Where do you think gold has gone?
This is important for any refiner.
It will not be economical to continue with these calculations.
Can you help find the deficit and control the various steps for possible corrections?