consolidation of Loss Gold thread

[AMS-Pro]

I have heard about the precipitation of gold with 1)hydroquinone and 2)hydrazine sulfate. I'm very interested in discussing this topic.

Lord, you should put those two in the same boat with Ammonia and just forget about it. Hydrazine can be explosive, you don't need that in your life.

 

[AMS-Pro]

A nice small silver cell producing about 300 oz a week (40 oz a day) would solve the recovering the gold from the chlorides and dissolving twice issue. Smallest professionally made Silver cells produce 3000 oz a week. Small footprint and will run exceptionally well with silver reduced from chlorides with no copper to foul the electrolyte.

View attachment 50572View attachment 50573

This is a beautiful piece of equipment, with such a small footprint too.

 

[Shark]

Take me down to the Paradise City, where the coffee is hot, and the gold is pretty. Ohhh, can we please, refine gold.
Sing to the tune of "Paradise City".
Now it's stuck in your head too.
You're welcome.

Yep, now it's stuck there.....

 

[AMS-Pro]

Yep, now it's stuck there.....

You're the first to comment on that. It was the end of a long day, cleaning out the electrowinning machines. Radio was on a classic rock station, and had some coffee to keep me awake, it was just one of those things. It's kind of a ritual now.

 

[Shark]

Quick question that might sound odd and may have been posted somewhere that I missed…. What are these made from? Coated metal or some sort of plastic?

 

[AMS-Pro]

Quick question that might sound odd and may have been posted somewhere that I missed…. What are these made from? Coated metal or some sort of plastic?

What are you referring to, the silver cell 4metals posted?

 

[Shark]

The AR reactor. I am assuming it’s some type plastic but assuming causes to many problems.

 

[AMS-Pro]

My first guess would be an epoxy paint of some sort.

My second guess would be a PTFE coating.

 

[4metals]

The AR reactor. I am assuming it’s some type plastic but assuming causes to many problems.

The one on the photo appears to be PVC but there are manufacturers in Türkiye who make them out of titanium which making heating them possible.

 

[AMS-Pro]

To me, it looks to be a coating on this system. If the frame has the same paint, from this angle, it looks like the paint was running on the upper left of the frame. Also the difference in color/reflection between the pipe and the plate it connects to. The hinges are welded on the access panel, as well. Maybe OP can tell us, it would be on the spec sheet for the equipment.

 

[AMS-Pro]

The AR reactor. I am assuming it’s some type plastic but assuming causes to many problems.

Now you've got me wondering about something trivial during the middle of my morning coffee.

Payback for the paradise quote, touché.

 

[4metals]

I suppose Gold Refinery could walk over to it and knock on it. That should tell the story, metallic or plastic.

 

[Gold.refinery]

To me, it looks to be a coating on this system. If the frame has the same paint, from this angle, it looks like the paint was running on the upper left of the frame. Also the difference in color/reflection between the pipe and the plate it connects to. The hinges are welded on the access panel, as well. Maybe OP can tell us, it would be on the spec sheet for the equipment.

The components that are directly related to the acid are all PP.
Structures are metal that has been painted and covered with PP.

 

[AMS-Pro]

The components that are directly related to the acid are all PP.
Structures are metal that has been painted and covered with PP.

So for clarification, the reactor is solid PP, and is not metal with a PP coating?

 

[4metals]

I have never seen a tumbler system made as coated or laminated metal. Probably because the threat of de-lamination with use.

The only coated metal vessels I’ve worked with are glass lined Phaudler reactors, but that’s an entirely different class of equipment.

Gold Refinery was due to either meet with or speak to the manufacturer about modifying some of the equipment. I wonder how that was received?

 

[Shark]

I hope he shares that with us. This had been a very enlightening post for me. I am sure there are others that have learned from it as well.

 

[AMS-Pro]

I have never seen a tumbler system made as coated or laminated metal. Probably because the threat of de-lamination with use.

The only coated metal vessels I’ve worked with are glass lined Phaudler reactors, but that’s an entirely different class of equipment.

Gold Refinery was due to either meet with or speak to the manufacturer about modifying some of the equipment. I wonder how that was received?

I was thinking more of a titanium tumbler reactor, that just happened to be painted with an epoxy paint/PTFE coating, or in the OPs case PP-H to match the surroundings/ease of cleaning.

 

[billgold]

Gold Refinery appears to have equipment that was designed for one specific refining path - which unfortunately has not defined by the manufacturer. For the process paths we normally use, the equipment seems to be marginal at best - such as the relatively useless stock filters and lack of adequate worker protection from fumes.

To complicate matters, I don't think that Gold Refining really understands the basic refining process, nor how to tell when one step is completed and that it is time to move on to the next. Nor does he appear to know how to tell when something is not proceeding correctly or how to recover from problems.

I personally think Gold Refinery would profit greatly by spending a few months with CM Hoke's book (plus the library) and running a bunch of small batch refining jobs. As others have stated before refining is as much an art as a science - especially when you need to minimize costs in materials and time. Without a thorough understanding of what is going on - neither labor or material costs can be minimized.

Nor has this discussion been particularly orderly or thorough, despite efforts to keep the discussion focused. For example, I have seen nothing on the composition of the feed stock nor what needs to be done in preparation for the AR digestion - if indeed, that should even be the first digestion step.

 

[Gold.refinery]

I don't think that Gold Refining really understands the basic refining process, nor how to tell when one step is completed and that it is time to move on to the next. Nor does he appear to know how to tell when something is not proceeding correctly or how to recover from problems.

Exactly

running a bunch of small batch refining jobs

We are doing this.

I will share as soon as the reports are completed.

(Of course, due to equipment defects, changes and suggestions from members are not quick.)

 

[EMRE]

I believe you will get the temperature you need to use sulfamic acid to kill off the excess nitric if you add it in the tumbler when the last addition of nitric has gone to completion and the reaction is still hot enough. The question is if the reaction is hot enough to begin with. This is something you will have to physically measure.

Originally I was skeptical about adding sulfamic to the tumbler because it will be difficult to add from the holes you can open up on the end of the tumbler where the exhaust to the scrubber exits. But then I remembered the charging hole. I added a red arrow pointing to the charging hole on a photo Gold Refinery provided.
View attachment 50347This hole is where scrap material is added to the tumbler and it is convenient because it is directly opposite the drain hole where the tumbler empties into the filter. If you stop the tumbler with this port on top, it can be opened and you can measure the temperature. If you have 80ºC or close, you can add sulfamic acid there.

Using the charging hole is good because it will allow you to carefully add the sulfamic and to monitor it closely so it doesn't foam too high.

Re-read the posts in this thread by Geo and Orvi about adding the sulfamic and add it carefully if it is at 80ºC or higher. do not over-add and look for the signs as described to determine when you have added enough.

Then you can add ice through the same hole and let the solution cool before filtering.


This is not as simple as it sounds. It is nearly impossible to know how much of the nitric you added has actually reacted and how much remains in solution. However your working experience can show you the right quantity for subsequent reactions. The nitric (70%) weighs 1.4 grams per ml. You know how many milliliters of nitric you added. Weigh out the quantity of sulfamic acid you will need to neutralize 100% of the acid you used (this will be too much, but it will help you do this properly in the future). Add the sulfamic, paying attention to the way it reacts and stop when it is complete. The activity of the reaction of the sulfamic acid on the solution should provide enough mixing that you need not seal up and spin the tumbler for this part. Simply place the cover over the hole to provide stronger exhaust from the scrubbing duct.

When you are done, weigh the remaining sulfamic that you haven't used. Now you can calculate what percent of the calculated sulfamic acid you actually used. Do this for a few lots and soon you will have a working value for future use. I would be surprised if it is more than 25% of the calculation made for 100% of the acid added.

I realize your system has the capability to add peroxide. I have never used peroxide in this fashion and the 4:1 aqua regia quantities I gave you per ounce of material should provide sufficient oxidizer.

Gold Refiner, please inquire what the wetted parts of the dosing pump provided for peroxide additions are. If compatible, the pump could be used for a slow constant nitric feed which will give you a continuous controlled reaction which could control NOx generation and provide a more constant warming effect for the reaction.

4metals

that charging hole may very well be under the water after all the acid was charged. Only if those Turks made that hole a bit further up! O))))