Help! New to forum! Have media from plating operation

[Absolutsecurity]

Hello,

Must be Gods will! I wandered upon this forum!
I recently had a friend call me and ask if I wanted to buy some more silver and along with the silver purchase came 90+ pounds of plating media(little balls and rice shaped steel) used in the plating tumblers that gets plated along with the connectors - well I ended up with about half the media being steel balls plated copper - nickle - gold the other half being silver plated . I had a friend send samples out for assay and there should be between 10 to 15 ounces of gold according to assay and 2 to 3 pounds of silver- a refiner tried to process some of the gold balls and had problems with the steel balls in the middle. I took the mess he handed back and it seems like I may have gotten a few ounces out of what he messed up using a AR prcess - in the AR I get a white or greenish white floaty layer that messes everything up and I spend a lot of time filtering - I am kinda new to AR refining and need some pointers - I have 30 - 40 pounds on little steel balls plated copper nickle gold and ther should be about 5 or 10 ounces of gold on them and I dont want to waste it away doing stuff wrong! And I havent even attempted processing the steel balls plated in silver yet for fear I will do something wrong!!!!!!!!
any help would be appreciated!

Glynn

 

[NuggetHuntingFool]

Perhaps they'd respond if you put up some photographs of your material.

Good Luck

 

[Absolutsecurity]

Do I just add attachment from my pictures?

Glynn

 

[Absolutsecurity]

I think I had to many pixels or something! This is the media - I have the box full of silver balls and the bags full of gold balls plated copper nickle gold with stainless or steel balls inside!

Glynn

 

[Absolutsecurity]

That I could use a rock tumbler to abrasively tumble the copper nickle gold off the balls and then use mercury to amalgum off the copper and gold and the AR the copper gold amalgum instead of messing with the steel balls in an AR reaction - ant help would be appreciated!

Glynn

 

[lazersteve]

Absolute,

Welcome to the forum.

I'd be happy to pay you for a few samples of the scrap and do some tests to determine the best route for recovery.

PM me and I'll send you my info.

Do you know if the steel is stainless and if so what grade?

I'll post the results to the forum.

Steve

 

[Absolutsecurity]

I dont know the type of steel - I was told it was stainless but it is magnetic!

Send me your address and I will get an ounce of each type sent out to you!
Thanks!!!!!!!!!!!!!

Glynn

 

[lazersteve]

Glynn,

PM sent. Check your PM box.

Steve

 

[jimdoc]

There are forms of stainless that are magnetic,
I think the steel used in catalytic converter cases
is one of them (304?)

 

[goldsilverpro]

THE NICKEL PLATING IS ALSO MAGNETIC!!

The balls are used as conductive media, in barrel (a tumbler) plating of small parts that are not 100% metallic. They assure that all metallic portions of the parts will eventually make electrical contact and all will plate evenly.

Based on the assay, the balls started out much smaller than they are now. They are used over and over until they get too fat to work properly. Therefore, there are, most probably, 100's of cycle layers, each with Cu/Ni/Au layers. The same with the silver ones.

Each refining deal is different, depending on the metals involved, their thicknesses, variation in the sub-layers, and the ball material, itself. I have run many 100's of batches of barrel ball media, barrel danglers, and plating rack nodules, all of which have these same multiple layers of various metals. When dissolving, certain metal combinations require a lot of ingenuity. The big refiners would simply melt them with extra copper (to lower the melting point) and ship the bars. We little guys often have to think harder than the big guys.

You will be much better off if you can work a way to just dissolve the plating, and not the steel. It would keep things much simpler, create much less waste, and use much less acid. It will take 45 gallons of AR to dissolve everything. You might be able to use only 1 to 5 gallons of acid, if you could use nitric to dissolve only the plating, but not the steel.

On the silver balls, you almost have to use nitric. Aqua regia would gum up the works with silver chloride.

I would first experiment with using just nitric on the balls, a few balls at a time. If the gold is of typical thickness, it will be porous and will allow the nitric to penetrate the gold pores and dissolve the Cu/Ni. On the silver balls, the silver will also be dissolved.

Stainless Steel Balls. This will work fine if the balls are of stainless steel, which is not attacked by nitric. Just make up a 50/50, nitric/water mixture and put it the hot plate. This is the first thing you should try, on a few balls. Assume they're stainless. You will soon know.

If of mild steel, nitric is touchy. If too weak, it will attack the steel. If too strong, the attack on the plated metals will be slow. Also, temperature plays a big part in this.

Here's what I would try first, with mild steel balls:

(1) Add a few clean balls to a small beaker. Cover with full strength technical or reagent grade nitric acid. Watch for a reaction. The best thing that could happen is that the nitric would eat all of the plating, leaving the gold flakes and steel untouched. A little heat can be applied to speed things up. If it's going too slow or, if nothing dissolves, go to step (2).

(2) Add 1%, by volume, of water to the nitric, stir, and repeat step (1). If that doesn't work, add another 1% of water. Repeat until you can dissolve all the plating layers.

Notes:
1 - Mild Steel - If it goes fast, especially in production, it may overheat and attack the steel. You may have to cool it a little.
2 - Mild Steel - I would guess that the mild steel will be attacked with about 5% to 8% water added.
3 - Mild Steel - There are 3 crucial variables - nitric, water, and temperature. Odds are good that a certain combination of these will dissolve the Cu and Ni and leave the Au and Fe behind.
4 - All Types of Balls - The gold flakes are separated from the steel by washing.
5 - Silver - In the case of silver, dilute the solution about 50/50 and drop out the silver with copper.
6 - All Types of Balls - Nitric may not work, but it's very much worth a try. If it doesn't work, use AR.
7 - All Types of Balls - If nitric does work, in production I would probably drill a lot of small holes in a small bucket and dunk the balls into a larger bucket that contains a few inches of acid.
8 - All Types of Balls - You might be able to whack a ball with a hammer or squeeze it with a vise, to see the layers. Nickel is fairly brittle.

Notes on Aqua Regia: In the total dissolving of everything, Fe, when finally exposed, will tend to go first and Au will go last. I have found that, if about 10% of the steel is still left undissolved but exposed, none of the gold will be dissolved. Test the solution for gold, anyway! This is partially predictable by the electromotive series.


After all this is said and done, the best way, in this particular combination of metals, would be to dissolve all the plating with a cyanide mixture or electrolytic cyanide, leaving all of the steel behind. The nickel might be a small problem, but could be solved with additives. The gold is then dropped with zinc dust. I'm not even suggesting the use of cyanide. That great privilege was pretty much taken away from us a long time ago.

 

[Absolutsecurity]

Thanks for the input!

I weighed out 200 g of gold plated rice sized/shaped tumbling/plating media and placed it in 100ml of con nitric acid in a 500ml flat bottom boiling flask. I have left it outside on my workbench at about 50 F - I will leave it there untill tonight and see what happens. Should I put it on my hotplate and bring it to a boil later? and if nothing happens then add 1ml of distilled at a time to see if that works?

Glynn

 

[goldsilverpro]

I would first use about 2 grams of media, covered with 50/50 nitric and strongly heated. You may have to boil it to dissolve the plating, but, probably not - avoid boiling, if you can. This is only an experiment - don't forget that you have 90# of the stuff to deal with. The first thing to find out is whether the core is stainless or mild steel. The hot 50/50 nitric won't attack stainless. It will very likely attack mild steel, unless it's some weird alloy that I haven't run up against.

 

[Absolutsecurity]

Im sorry - I didnt fully read your post and went ahead and did a big experiment :shock: as ussual instead of a small controlled one - Well I have 200 g's of rice shaped and likely sized media in 100 ml of 80-90% nitric the acid is starting to turn green and I saw some small bubbles - should I leave it alone or heat - add water???????

G

 

[goldsilverpro]

Is it stainless or is it mild steel? The answer will determine how you finish the 200 grams. Take 1 gram of media, cover with 50/50 nitric, and boil until the action stops. Add a little more acid to see if more action occurs. When no more will dissolve, look at the media. If all you see is non-corroded metal, you have stainless. Once you've done this, rinse and let it dry, and post a photo of the stripped media.

 

[Absolutsecurity]

Got it on the hot plate doing a sane as instructed amount to see whats inside - its bubling away!

THANK YOU!!!!

G

 

[Absolutsecurity]

really doing much :? - how many hours and I just unplugged the hotplate and set it aside to rest - no real noticable change - I think due to the fact that this came from a mil-spec plating operation that the plate might be to thick. The batch in lab grade nitric acid isnt doing much but looking like boiling chips. I tried another batch with hybrid nitric via soidium nitrate and sulfuric acid and that one acted like an AR reaction with red fumes and has foil floating around but seems to have peatered out - so I added some nitric lab grade to see if it would keep going and that was a mistake - now there is with curdy stuff in the mix

Man I gotta stop playing mad scientist! :twisted: :twisted: LOL!

G

 

[Harold_V]

There are forms of stainless that are magnetic,
I think the steel used in catalytic converter cases
is one of them (304?)

None of the 300 series stainless materials are magnetic unless they are work hardened, and then only mildly. The 400 series is magnetic, as are the precipitation hardening varieties---17-4 PH, 17-7 PH, 15-8 PH. There are others that are also magnetic, such as A 286.

None of the 300 series can be heat treated, although heating to redness will relieve a work hardened condition.

If the balls have but one layer of plating, not repetitive layers, stripping in a sulfuric cell would be in your best interest. If they have precious metals covered by base metals (copper and nickel), that, of course, won't work.

Harold

 

[goldsilverpro]

I'm guilty of making this thing more confusing than it really is. This type stuff you have is one of the most difficult things to refine (or, at least, dissolve) on the planet. It is made up of, most likely, 100's of multiple layers of multiple metals. You really don't know if only Cu, Ni, And Au are involved. Maybe, the guy used them for other metals that you can't see. Maybe, the Ag ones are the same as the others, except silver was the last thing they were used for.

Knowing the huge metals variations and numbers of layers found on this stuff, I tried you get you to experiment on small amounts. I first picked 50/50 nitric, because, if it worked, you would be better off. Also, the info made it sound feasible. However, it doesn't seem to have worked. The gold could be too thick. There could be other metals involved. Before eliminating nitric altogether, I would try boiling 80/20, nitric/water on a couple of pieces.

If this doesn't work, you have to try other things

Have you tried aqua regia yet, on a couple of pieces? You may have to heat it. Let me know what happened.

Send Steve some samples and let him play with them. I wish I had a lab.

 

[Absolutsecurity]

So I checked the rice grains in nitric and nothing happened - then I check the rice in hybrid nitric and it ate away at some and I had foil floating around in green acid with white percipitate that occoured after I added a little distilled water (AS POSTED IN MY DISTILLED WATER POST THIS HELP SECTION)

I decided to pour off all the fluids into seperate beakers untill I can get answers and figure stuff out!

I still had the itch :twisted: so I noticed a batch of the silver balls I did in hybrid and it was a yellow white mess of gunk with grey and copper balls - SOOOO I poured off the mess rinsed the balls and added con nitric to see what the base material of the balls might be as GSP requested - the balls took off red fumes (good nitric!) AND NOW I HAVE A BUNCH OF GOLD BALLS! LOL! LOL!

DAM THESE GOLD BALLS!!!!!! JUST LIKE YOU SAID GSP , DONT KNOW WHAT OR HOW MUCH THEY ARE PLATED!!

But I do know that this aerospace mil-spec connector manufacturer - BIG NAME - closed the plating operation and moved out of town - they only plated MIL-SPEC and only plated copper nickle gold and silver! So those are the four metals on the balls I WILL GET TO THE BOTTOM OF THESE BALLS to find out what they are stainless or mild steel! (I was told they are stainless)

Some foil was floating in the green blue acid above so I am going to see what happens overnight!

I NEED HELP!!

WHAT DO I DROP FIRST OUT OF ACID AND HOW?

90 + pounds of balls and more gold than I thought ( DAM SILVER BALLS ARE TURNING GOLD :evil: ) and IM LOST !!!!!!!!!

Glynn

 

[Harold_V]

From your description, I think you'd have reasonable success by processing with hot nitric acid and water. The only thing that wouldn't go in to solution would be gold (and, hopefully, the core piece), and with a bit of luck, the gold won't be too thick to prevent penetration of the nitric. By prolonged boiling, you should be able to penetrate to the core, assuming the gold is porous enough.

For starters, you're making a mistake working with a large volume of these things. Start with just a few pieces and test various methods. That way you won't find yourself in a position that you would have been better off to avoid. Once you've determined a good process, you can go for it with confidence.

The nitric boil is a good place to start. If, by chance, the core is stainless, you're home free. Stainless (300 series) is not dissolved by nitric. It is also non-magnetic, so if the items you have are not magnetic, that's likely what they are.

If the above doesn't work, your choice might be to boil them until a gold layer is exposed, then strip the gold with a sulfuric cell. Return the pieces to nitric and water, and repeat until you're down to the core piece.

I strongly advise against the use of AR to strip the gold, if for no other reason, it will react with the core piece, as well as the base metals. Keep a good thought that the core isn't iron (steel), which would not be in your best interest. Another negative with AR is that it will form an impervious layer of silver chloride on the items, possibly stopping the process.

Regards recovering the values, don't worry about that right now. Until you have a process that's viable, you'll not have anything to recover.

The spent nitric and water solution will contain silver, at least it should. It can be recovered either on copper, or with salt. I recommend the copper process.

When (if) you process as I suggested, don't use any more nitric than is necessary. Start with a small amount, with water, and allow it to work. If action ceases, pour off the solution and start with more. The whole idea is to not have excessive nitric when the operation is complete. If you recover the silver with copper and there's excessive nitric, it will dissolve the copper until it's well used up, creating lots of fumes and wasting your copper.

Regards the nitric process-----if you dissolve silver in the presence of copper, you can expect the copper to precipitate the silver unless you keep the acid level up. If you notice a gray substance forming on the items, that's likely silver cementing out of solution.

Hope some of this helps!

Harold