advice?

[butcher]

Great job, little more processing and you will have a little button

 

[Gold Nut]

butcher,
You stated that 2% of gold is lost due to very fine sediments or in filtering. Would it be possible to burn the filters and recover what's in them?
Gold Nut

 

[butcher]

yes it is very important to save filters and have a stock pot, if you do much of this you will start to see they really pay off over time. as far as I know there is no such thing as 100% recovery in recovery processes, and also losses in refining processes, saving filters and having a stock pot can help recover some of these processing losses.
I cant remember how much Harold said he recovered from saving his solutions but it was a sizeable bonus maybe will get him to tell the story again?

 

[Harvester3]

Greetings
Thanks Butcher. Couldn't have gotten this far without your help.

Steve, the foils are from a couple of experiments; one was 70 fingers using your AP process, which works very well.
I'm going to get an aerator for that process.
The other was using home made nitric placed in the freezer overnight, pouring off to remove any frozen portions. It was used on a group of heavy pins and 2 processors (Digital server CPUs with the 2 heatsink lugs)
The thing I like about nitric is, you never lose sight of the gold, although now I plan to use HCl/Cl to further concentrate the gold.
I liked the way the copper cage worked in your video.
There seems to be a number of process' which one can use to get the gold; I'm sure some are better on certain types of material than others, and am continuing to study here for proper technique.

BTW, although I've seen many mentions of it, I haven't found the process for rejuvenating the AP mix. Could you please give us the 2 minute tour?

Also, I'm curious if anyone has developed a good procedure for whole motherboards; I've got some server boards which have a great deal of gold tracing, which I want to send to a friend who's been giving me advice on this project, but before I send the load I'd like to know if it's going to be a good load, or if the motherboards are more trouble than they're worth.
Thanks you all. I appreciate it.
Jim

 

[Oz]

Steve has a wonderful PDF on his site that will give you all the technical details on AP. Just click on the link under anything he writes.

 

[Harold_V]

I cant remember how much Harold said he recovered from saving his solutions but it was a sizeable bonus maybe will get him to tell the story again?

It's not much of a story, but it was one hell of a nice savings plan. You must keep in mind, I refined on a full time basis for years, so the numbers aren't reasonable for anyone that refines as a hobby.

My waste material yielded more than 200 ounces of gold, and roughly the same amount of silver. It also contained a large amount of platinum and palladium, in part because neither of them will precipitate from dilute solutions. I relied on my stock pot to recover traces, and did so for more than 20 years. The contents of the stock pot were included in my waste materials when they were processed.

All of my waste material, which had been incinerated and stored, was fluxed and processed in the tilt furnace I built. There's a picture posted, below. In order to recover the values, I made a point of allowing silver chloride to be recycled with the wastes, to act as a collector. It was a long shot, but worked exactly as planned.

An assay of the flux from the furnace operation proved to be so low in values that it was not acceptable for further processing by a commercial refining house that specialized in processing such low grade material. The flux recipe, being extremely aggressive and thin, contained no prills. I consider my experience to have been a total success.

Harold

 

[butcher]

processing of whole boards capacitors and large metals and some components removed first, can be done but it gets complicated and time consuming, because of solders and base metals that end up in solution, they are worth it to a hobbyiest that is not doing it for profit.but it can be dangerous because of all the lead and other heavy metals, so an understanding is needed of how to deal with these safely.

 

[Harvester3]

Butcher
So, you have said understanding of the particular process' for PM removal of really nice looking boards? Let me know, ok.
Harold,
Do you use the same ingredients for a reducing flux or oxidizing flux, or do you vary ingredients based on the concentrates being refined?
Thanks you all.
Happy New Year.
Jim

 

[Harold_V]

Do you use the same ingredients for a reducing flux or oxidizing flux, or do you vary ingredients based on the concentrates being refined?

I didn't consider this process to be refining, but reclaiming, instead.

As far as fluxing is concerned, my attitude was that I had to reduce silver chloride to elemental silver, my prime objective. That, and a very fluid flux, so there would be no prills. Not being a chemist, I researched to the best of my ability, then made some decisions based on what I had read. I concluded that the flux recipe, below, would function adequately. I was more than satisfied with the results, the only complaint being the flux was extremely aggressive, and did severe damage to the furnace lining. While not pleased, it was not unexpected. When I compare the cost of building the furnace and the repairs that were necessary, to the yield of values, it was a no-brainer. Recovery costs, compared to the yield, were virtually zero.

Hope this reply helps----just know that I used only one flux recipe for recovering values----all of which were mixed together, regardless of the source.


(3) parts waste material
(1 1/2) parts silica sand
(3 1/2) parts soda ash
(1/2) part fluorspar
(2) parts borax
water to make a batter similar to pancake batter.

The "batter" was poured to shallow forms (ice cream bucket lids) and allowed to set, which took only minutes. They were removed and allowed to dry before introducing them to the furnace. They were struck in the center to yield pie shaped pieces, small enough to fit the furnace port. The furnace was charged from the exhaust port, for there are no other openings.

By creating solids from the waste, there were no losses to dusting. That was one of the pleasant surprises of my experimentation. I did not expect the material to react as it did.

Harold

 

[Harvester3]

Thanks Harold,
So, in recovering PMs from E scrap, and ultimately refining the con's, would you recommend this recipe as a good starting point for a flux?
Also, what method does one use to cleanse used flux from a crucible other than remelting?
Thanks
Jim

 

[Harvester3]

BTW, nice looking furnace!

 

[Harold_V]

Thanks Harold,
So, in recovering PMs from E scrap, and ultimately refining the con's, would you recommend this recipe as a good starting point for a flux?

If you've followed many of my posts, you may know that I was not involved in processing e scrap, although I did run a small amount, particularly early on, before I found I had a serious business on my hands.

With that in mind, I would suggest that the flux I used would serve quite well, but you might have to work out some of the ratios. If your feed had little or no silica, you may need more sand, or you may be able to reduce the amount of fluorspar, or even alter the ratios of borax and soda ash. Again, not being a chemist, it's not easy for me to understand the relationships between the constituents and how they interact with one another. I know that my feed was fairly high in silica, which is one of the important things you need to know. The source of silica in my waste was from incinerated furnace filters, which were used in the jewelry industry in their polishing systems. They have been incinerated and chemically processed for values, but you never get it all---so all of the residues from polishing wastes were a part of my waste materials. Assuming a person was to process incinerated boards, that would be a good source of silica-----plus the residual solder and traces would behave as collectors.

Also, what method does one use to cleanse used flux from a crucible other than remelting?

I can't think of a better method than to heat the vessel with fresh soda ash. In spite of the opinions that have been expressed in the distant past, I found that soda ash will reduce oxides and clean dishes perfectly well. I used to clean melting dishes with soda ash, returning them to the owners. It was a service I provided as a benefit for using my refining service. The cleaning process thins the dish, but it is perfectly clean when the operation is finished, and there's a nice button of alloy that was processed for values. All in all, a win/win proposition for both me and the customer.

I would think that you could clean crucibles the same way, but you take a large piece of life from them when you do. Soda ash is very aggressive towards refractory materials, so you may be better served to use a flux recipe that does the work without creating a viscous slag. It will be correspondingly hard on crucibles, but you won't have to heat them for cleaning, only for use. That is a win/win proposition, too, for your slag won't contain prills if you've done your homework. Your recoveries will be better, with less work in cleanup.

If you don't have one, get a cone mold. It is nearly impossible to work with flux without one.

Thanks for your comments on the furnace. I was quite proud of it, especially when I put it to work.

Harold

 

[Harvester3]

Not to change the subject, but I have an old iron ladle that probably was used to pour lead in.
Anyway, quite some time ago I attempted to reduce some material in it. It seems the melting point of cast is close to the same as the material I wanted to recover, and it bonded very well to the ladle. Any idea as to how or if it's possible to recover the PMs from this antique?
I didn't have a crucible or dish for melting at the time, and got impatient.
Silly mistake I know.
Thanks. Happy New Year you all.
Jim

 

[Harold_V]

Anyway, quite some time ago I attempted to reduce some material in it. It seems the melting point of cast is close to the same as the material I wanted to recover, and it bonded very well to the ladle.

It need not be close to the melting temperature, and likely was not. The solvent power of molten metals is almost always dismissed by people---but that's a mistake. Low melting temperature elements (lead, for one) are used routinely to recover elements that have much higher melting points, with excellent results. The target elements need not melt, they can be dissolved.

Any idea as to how or if it's possible to recover the PMs from this antique?

Depends on the material involved. An example might be elements that are soluble in concentrated sulfuric acid, which cast iron can withstand. No simple answer to your question, but I'm inclined to think that you won't be able to recover without damaging the ladle.

Harold

 

[Oz]

Since you think this ladle has been used for lead in the past it is doubtful that you will ever use it for food. If that is the case then I would melt some lead in it by heating to a dull red heat. As Harold mentioned lead will dissolve gold and alloy with it, but I am reasonably certain that iron and lead will not. As long as the cast iron surface is relatively smooth I think you may be able to peal lead residue off. This was something I was actually put on to by Harold as well, that the US mint used to do something similar to recover gold from iron tools, and you could always test this on some scrap lead and cast iron first.

Correct me if my memory is incorrect or I am flawed in my thinking Harold.

 

[Harvester3]

Thanks Harold.
Near as I can tell and remember, there's about 6 grams of gold along with maybe 1.5-2 grams of copper involved in the situation. Also, now that I think about it, the ladle is iron, but I don't think it's cast. It really grabbed the gold well!
Thanks for your help.
Jim

 

[Harvester3]

Oz, thanks for that info. I came across the ladle the other day and after looking at it, it probably has more than just what I mistakenly melted in it. If the lead trick works, we might recover some amount of silver as well.
Keep you all posted.
Thanks again
Jim

 

[Harold_V]

Correct me if my memory is incorrect or I am flawed in my thinking Harold.

The information I recall is where gold is separated from iron by using silver. If lead was to be used, one would likely have to revert to cupellation to eliminate the lead. Today, that isn't an acceptable process unless ample recovery measures for lead are employed.

Blue gold is an alloy of iron and gold, which will readily alloy, although the properties of the resulting alloy leave a great deal to be desired.

If memory serves, what I had posted was a method from separating gold from iron. Silver and iron do not alloy. Gold has a greater affinity for silver than it does for iron, so by melting gold contaminated iron in the presence of silver, the gold will, for the most part, migrate to the silver. When the lot is poured to a mold, unlike most scenarios where the metals remain mixed, there is stratification, with the gold/silver alloy on the bottom, then a layer of iron, then a flux layer. There would be a layer of sulfides between the flux and iron, assuming there are any sulfides present.

I have experienced the operation when processing (in a furnace) material that was high in sulfur. All of the sulfide layers were re-processed when combined, with lengths of scrap steel inserted in the crucible. Values combined in the sulfide layer were liberated, yielding the values that were locked up. The nature of the sulfide that remained was changed considerably. It started out with a rather coarse grain structure, but resembled cast iron when the values had been liberated.

Harold

 

[Oz]

I wasn’t positive but with you mentioning it, it was silver. He has mentioned that he has considerable silver already in it but if he added more silver he may just make a greater mess. Somewhere on my computer I have the entire process but I think they would put the iron/silver with a little silica in a cone mold similar to what you use at the end of the day in the furnace. After they had it to a molten state they would shut down the furnace for the night to cool gradually to help stratification and in the morning they could usually strike it with a hammer and have it separate cleanly.

Depending on how badly he wishes to save the ladle he may be able to grind it out with a grinding wheel on a dremel depending how hot he originally got the iron. The grindings could then be processed. 6 grams of gold is worth more than most iron ladles are.

I will try to find the document. My apologies for the inaccuracy, and thanks for the correction Harold.

 

[butcher]

Somthing to think about, iron ( better if silicone involved) would be more resistant to concentrated nitric than silver, hot washing with brush just inner cup not keeping in contact with acids long may help, neutralizing between wash, this may wash out some of the base metals, and silver. then maybe a few hot HCl/bleach brushings to inner cup to get gold, might work.
Another thought a litharge flux borax, soda ash or washing soda and flour, or corn meal, if hot enough lead will pick up gold and if ground glass (silca) in flux maybe the Iron oxide of the tool may flake as glass tries to collect it and gold and silver picked up almagaming in the lead.
Or electrolisis cup as anode and a cathode held inside cup, Iron should hold up to concentrarted sulfuric somewhat,
these are only things you can ponder. on ways to try and get your values from the cast iron melting ladel.