# A question for the chemists



## maltfoudy (Jan 21, 2009)

since most of the material we deal with is mostly base metal or other scrap would this work... instead of using AP to get rid of base metal how about using 67% Calcium hypochlorite and water or some other basic solution to dissolve the gold and leave the base metal? and if it is possible how would you go about getting the gold out of that mixture. or is this not possible? i have heard that Calcium hypochlorite and lye will will dissolve gold but this is just 2nd hand info. and i wouldn't have an idea where to start. i bought a 100 lb barrel of 67% Calcium hypochlorite for 2 dollars a while ago,with the wife putting the nix on the acid methods maybe i can get this one by her.


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## butcher (Jan 22, 2009)

I have heard of it used with muratic acid as a leach of ore, but it will not be selective,will dissolve most of the metals,base metals easyier than the gold, I think you will need alot of HCl about 10 gallon/ liter.to get ph needed, to cause HClO to form, from HCl + Ca(OCl)2, have also heard of it used with cyanide, so you are still not away from acids with this, unless someone else knows of another method, I see ths as a bleach sustitute in the HCl/Bleach method


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## Harold_V (Jan 22, 2009)

butcher said:


> also heard of it used with cyanide,


Red flag time. 

Cyanide must be kept at a pH of 9½ or above, to prevent the liberation of hydrocyanic acid, the deadly fumes that are used in a gas chamber. 

Maybe I don't understand what has just been mentioned, but if it revolves around mixing HCl and cyanide, it's definitely NOT a good idea. 

The only case I can think of where acid is introduced to cyanide is when I processed two batches of extremely high grade gold ore. I used bromine with cyanide, and had to control the level of free lime in order to prevent the lime from killing the bromine. My target pH was, as I recall 9½, which I accomplished by adding small amounts of sulfuric acid to the agitation tank before including the cyanide/bromine mixture. 

Be safe-------do not mix acids of any kind with cyanide. 

If I misunderstood the post, forgive me----I'm getting old and goofy. 

Harold


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## Platdigger (Jan 22, 2009)

If you have C.W. Ammens book, 2nd edition, he describes in the very beginning of the book a barrel method for gold ore as well as electronic scrap using chlorine and sufuric acid as the oxidizer. 
But, you have to seal up the barrel when you add the acid or the chorine gas is going to get you.
He mentions using bleaching powder (chlorinated lime).
And that some bleaching powders are a mixture or calcium chloride and hypochlorite.
Randy


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## Lou (Jan 22, 2009)

Randy, that is a specific application of calcium hypochlorite. The barrel process is tried and true, but it's better for ores that are mineralized and without free base metals. If you have an ore that has a lot of sand and fairly inert gangue in it, then it'll work very well. If you have an ore that contains a lot of easily oxidized iron or copper compounds...good luck to you.


I can see no reason why anyone would mix cyanide with hypochlorite--in fact, that's the recommended method of _destroying _cyanide.


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## maltfoudy (Jan 22, 2009)

thanks harold,but i have NO interest in messing with cyanide,the wife put the nix on the acid method and i was told to check out Calcium hypochlorite and lye as a possibility and i am just trying to find a safer way to do this without acid, as i really do not want to send my stuff off. i don't see much of a challenge in that,and i hear all the horror stories about how the refiners screw you hard.Maybe iodine? or bromine? i have heard these also work but i think these are for ore and not e-scrap.


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## Harold_V (Jan 22, 2009)

Gulp!
Yet another senior moment, it appears. 

I just re-read the post. How in hell I read HCl is a mystery to me. 

Amazing what a night's sleep can do to put things in focus!

Harold


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## butcher (Jan 23, 2009)

I hope no one misunderstands my post I was not suggesting HCL and cyanide,
was stating that calcium hypochlorite has been used as a pretreatment to ore in the cyanide processing of ore.

The way I explain things, and type maybe, I should not use the two in the same post,Shoot I even confuse Harold, luckily he usually come on at night and straightens out the confusion I cause trying to help with my lack of english skills 


if you dont want to mess with these acids etcetera, consider sorting your material and selling it, it would possibly be more profitable than extracting the gold. :wink:


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## Harold_V (Jan 23, 2009)

butcher said:


> was stating that calcium hypochlorite has been used as a pretreatment to ore in the cyanide processing of ore.


Lou commented that calcium hypochlorite is commonly used for cyanide solutions prior to disposal. That's what I used when I'd discard mine. I can't help but wonder if using it before cyanide would be a bad idea? Anything you did that would destroy cyanide would certainly increase the demand for its use. Just a matter of curiosity-----I'm not suggesting you didn't read of the process. 

Harold


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## goldsilverpro (Jan 23, 2009)

Sodium hydroxide plus a hypochlorite is commonly used to break down cyanide to cyanate. Although cyanide is 1000 times more toxic, I believe that there disposal restrictions for cyanate. Another method for doing this is covered in a DuPont patent - 3617582. It uses formaldehyde, H2O2, and epsom salts. INCO has a sulfite process.

About the only way to break cyanide down to it's elements is to use hi-temp hydrolysis. There is a lot of info on the internet about this. I have also read that incineration will work but I don't know the parameters or how safe it is.

I have experimented with electrolysis between two steel sheets in a cut off 55 gal plastic drum. By analysis, the cyanide concentration dropped quickly until it was down to a low level. After that, it went very slow. I don't know what the by-products were.


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## maltfoudy (Jan 23, 2009)

most of my material is sorted,i have about 50 lbs of clean pins,15-20 lbs of memory sticks,about 15 lbs of ceramic cpu's,about 10 lbs of slot cpu's and 5 lbs of misc fiber cpu's.8-10 lbs of cut finger edges. the pins are very heavy plate and i hate to give em up.the dates on the boards they came from were dated from 1972-1984,and i still have tons to go through, i wouldn't mind finding someone to do this stuff for me,but i have heard some real horror stories about the few refiners that i know about. lazersteve had said he does it for a % but not sure he would have the time for all of what i will have by spring.as it might be a pick-up full by may.because i have 4 pallets or about 2 -3 tons of boards that were in a fire and i fiqure it will be real easy to sort.


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## Anonymous (Jan 23, 2009)

I use a split cell with potassium nitrate electrolyte to do my pins. I do not think that would work for anything that will not make good electrical contact.

I shred my pins to expose more of the base metal. I also have fingers in there because I grind them off (metal only) with a dummel tool. This yields me a fine metal powder that helps with maintaining electrical contact.

Base metals go into solution on the anode -positive cell- and migrate to the cathode - negative side were they are reduced back to fine metal powder. My bridge is tight weave fiberglass high temp electrical insulation material.

The gold stays in the anode cell becuase it never goes into solution.

I do not know how hard or if this is scaleable to an operation of your size.

I am only running material from
10 or so pounds of boards, and using a cell charger for the power. It is slow but once I have cleaned all the parts I want off the boards I put the metal parts in the cell and forget about it. I occasionally stir to reconnect any isolated parts.

I have a computer power supply that I was going to use to make a larger set up. But I just don't have acess to enough material. I am only running what i happen to find thrown away and buying small lots on ebay when they are not too overly priced. 

Also in the end if you want high purity you still have to use the chemicals or some other process.
I do however use tiny amounts of the acids now because I only need enough for the highly concentrated gold powder.

Hope this helps 

Jim


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## Anonymous (Jan 25, 2009)

I am posting pictures of the kno3 cell I use.
I got the cups at walmart stainless 1.5 oz, 4 for 1 dollar. Brazed tabs to side for electrical connection. 
I heated to dull red for a couple minutes to get a good oxide coating to help protect the cup itself from decomposing. Then lined the inside walls of the cups with hi temp silicone, making sure to leave the bottom uncoated - this is were the pins make electrical contact.

The salt bridge is fiberglass wire insulation, but you can just use a piece of filter paper.

I am using a cell phone charger, .8 amp at 5v.

I guess you could upscale with dog food bowls and a larger power supply.

Jim


Well I can not get them to attache directly from my blackberry if anyone wants to see them let me know and I will email the pic to you, and you can post or not.


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## g_axelsson (Jan 26, 2009)

Here is a photo of Jim's setup.


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## jamthe3 (Jan 26, 2009)

What material are you putting in & if when you say "slow" 'bout how long does it take you to do your 10 lbs. That little cup holds 10 lbs or do you divide it up into small amounts and keep adding to it?

Sorry, for so many questions...I'm not only not the sharpest tack in the box, I'm quite dull & dense.


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## Anonymous (Jan 26, 2009)

I only put metal items in, pins and metal powder from grinding off fingers. I only am using a .8 amp power supply which is the main reason it is slow. My set up is small about 2 ounces of raw material at a time. I never really paid attention to the time because I am forced to mainly buy my material on ebay so I don't buy very much because it is always price way over content.


I built my set up for 3 dollars it is mainly just a test vehicle that I never up sized because of limited raw material.

Jim


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## butcher (Jan 30, 2009)

calcium hypochlorite preatreatment of ore. web search:

http://www.google.com/search?hl=en&q=+calcium+hypochlorite+has+been+used+as+a+pretreatment+to+ore+in+the+cyanide+processing+of+ore.+&btnG=Google+Search&aq=f&oq=

for information only


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## nicknitro (Jan 31, 2009)

I have heard of an alternative method for "crap mining" the Amalgamite method. It involves a material "unsure of metals involved", but I thought amalgamwas silver and mercury. Again unsure, have to consult the experts. But essentially you bring the amalgamite to a boil in a regular fry pan on a hot plate in open air " Boards will emit toxins when broken down" , then add the boards or any materials you are refining. The amalgamite absorbs the gold for later dropping, and the crap stays floating on the top for skimming. 

If you are doing mostly pins, probably Lazersteve's reverse plating method with a cell is best for you. Still involves quite a few acids, but the main acid Sulphuric is pretty stable amongst the other fume producing ones like HCL, and nitric. 

Good luck, and don't lose hope. There are many many ways to skin a plated pin. LOL

Nick :wink:


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## Platdigger (Jan 31, 2009)

The "Amalgamite method" has been discussed in another thread...or two.

I don't think you would want to boil it. At least not were anyone could breath the fumes created.

There is even a group forum on ebay.
Randy


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## maltfoudy (Jan 31, 2009)

we have had the amalgamate talk,it is bismuth and i think we found that the "secret"item used to get your bismuth back was ammonia,i'm looking for some bismuth shotgun shot to try this on some low grade stuff,as i refuse to pay 37.50 a pound for bismuth from goldco.


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## jamthe3 (Feb 9, 2009)

I have 13.75-0-46 kno3, how would I make the electrolyte; i.e. how much of what liquid / acid to how much kno3? I'm assuming it goes in both the anode and cathode sides of the split cell.

Thanks,
John


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## Anonymous (Feb 9, 2009)

John
Just dissolve in water. You can experiment, I just put some kno3 in a bottle with water and shake, when there is a little in the bottom that does not dissolve you have your electrolyte. You could try copper nitrate also, that is what the cell is based on, I just did not have any at the time so I started experimenting.

Jim


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## jamthe3 (Feb 10, 2009)

Thanks for everything James, I hooked it up and put in a little wire just to get my feet wet so to speak. Some ag plated crap, so no values to lose per say, but figured it would be fun to get the feel for it. Just out of curiousity, the silver would migrate over w/ the other base metals also wouldn't it. Guess I'll find out when the "dust" (lol) settles.

I really appreciate that kind gesture!!

Cheers,
John


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