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I have this mixer. Picked it up a couple months ago when laying the block foundation for my garage addition. It will be used for grinding whenever I get to it.
The first load, ran the shred through the paper shredder twice, good gold recovery.

2nd load shred only made it through the paper shredder once before it died, gold recovery was fair. Still a lot of gold plated material encapsulated in plastic and metal casings.

Dry run was also much better, the foam was very thick and it cushioned the material, keeping it from being abraded.

Usually passing a flame over foam will collapse it, or spraying water onto it. First tried the flame all it did was heat the metal foam red hot leaving the cell structure intact - water also a waste of time.

Two days dealing with the foam, mind you that 10 grams is good quality gold / possibly some palladium and silver.

I have the cons from the first run in aqua regia at the moment, from the first hot nitric wash we know there's no copper. The leach is green, think it's safe to assume - gold, palladium and silver to be present.

First metals to give up to the leach have actually left most of the un-reacted gold a beautiful tan color. Once I have some decent weather will proceed to the final refining stages.

2nd batch of cons has a lot of base metals present, it's currently in sulfuric acid.

Worried about breaking my glassware from thermo shock working outdoors so the leaches are currently at ambient temperature which is below freezing.

No heat in my shop yet so I moved everything into my kitchen. Time to haul out the junk.

What you have seen in this thread of my gold concentrates all came from what you see in the 20 liter pail.

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First load into the mill ran five hours dry, 2nd load four hours dry then another four hours wet.

I've kept the water from my wet run to be used as rinse on the shred coming out of the mill when I rerun the crap in the 20 liter pail.

Just have to figure out someway to make the shred a bit smaller to expose the gold.

Ohiogoldfever if you give your mixer a work out perhaps you would consider append your results to this thread.
 
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I think you have maybe discovered the path to floatation , using the reagents already combined in the make up of the boards. Perhaps a person like Deano can shed some light on the chemistry of what is happening. It would be a great idea if electronics manufacturers could take the reprocessing into consideration, making recovery a simple, green step.
 
This is the gold from the last load, used dilute sulfuric to remove base metals. Nice thing about sulfuric acid is that it's not voilent coming into contact with finely divided base metals.

Even though it's below freezing outside I could not resist, coffee carafe in a hot water bath protects it from thermoshock.

Filtering out the leach elements now using distilled water, this is not refined gold. I like to have my cons as clean as possible before going to the refining stage. Less chance of a boil over when the cons are clean.

Bottom image the heavies, 20 grams.

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Sulfuric acid used to remove base metals, maybe some silver and palladium present.

Plating out the metals, easier to work with concentrates.

The recovered metals, good candidate for smelting.

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My observations are, and my theory is,

Top to bottom, stainless steel anode, once the metal ions below nickel had been depleted, the anode became sacrificial. Refer to electromotive series chart.

The liquor now contains nickle ions causing the color change.

Image 1, Starting point, green liquor.

Image 2, Precious metals stripped out, liquor is now blue.

To remove the nickle ions, I'll switch out the stainless steel anode for a carbon electrode.

Image 3. nothing exciting here just the collected filtrate.

Image 4, incinerated filtrate, observation - gold on filter paper the whitish substance un-burnt sulfur residue from the acid.

Image 5, the recovered metal.

Image 6, the weight.

Image 7, Electromotive series of metals, how can you use it to your advantage. Metal precipitants and electrolysis come to mind.

Most of us use copper to cement silver any metals below copper will be recovered in your silver cell as slime.
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While stripping out the metal ions had copper been present is would have been visible in the precipitate as copper metal.

During incineration I did notice some purple in the filter paper, this would have been gold.

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Had a good day, picked up my acids got to speak with the chemist and learned how to precipitate palladium as palladium(II) sulfate.

On the way home stopped in at my favorite scrap yard and picked up a couple of gear reducers. The stainless one shown below is 40:1

The food plant where these come from discard the whole unit when a motor burns out, any single phase pump style motor will fit the flange.

In addition to the two reducers, picked up some screens used in a hammer mill, these came from the ethanol plant. I'm guessing AR 450 or AR 500 metal.

I'm very pleased with how quickly I'm able to gather up the most difficult and expensive parts for my shredder build.

Most heavy construction and farm equipment uses AR plate or sheet, Danny is going to give me a call when either some 1/4" or 3/8" material hits the yard.

He is also going to promote the collection of e-waste, he already has some mother boards but they were inside the shop behind bins that would have to be moved to access the boards. He said the crew would be back tomorrow.

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Your probably wondering how I can couple the gear reducer to a hexagonal shaft

Lovejoy manufactures couplers to connect dissimilar shafts.

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Unrefined palladium with a bit of gold, this will be going to EDI in Ontario.

It appears to me the palladium content on e-waste exceeds the gold content.

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stoneware - I am sorry but I have to call total B.S. on this thread - especially concerning the claims you are making on the recovery of PMs you are getting from the very small amount of VERY LOW grade boards you have run through your system

I am not even sure where to start here - but - lets start here -------

At this point you have run one 5 gallon (20 liter) bucket of shredded LOW grade boards through your system

What does that bucket of boards weigh ? --- 25 - 30 pounds (11 - 13.5 kg) --- lets go high & call it 50 pounds (22.72 kg)

On the "average" - one ton (2000 pounds) of nothing but modern day mother boards (which are higher grade then what you are running) will recover "about" (plus/minus a few grams) 3.5 toz gold (or about 109 grams)

That means 50 pounds of (modern day) mother boards would give you a recovery of about 2.75 grams gold

Yet you are posting numbers like -------
HCL wash, rinsed and dried 159.7 grams from less than half a 20 liter pail.

Gold, palladium. silver with perhaps a bit of lead expected on the final refin
(posted Nov 9) --- per the bold print - 159.7 grams (Au/Ag/Pd) from LESS then a bucket (so less the 50 pounds) --- NOT A CHANCE - you will be lucky if there is a gram of all 3 PMs in that 159.7 grams

Then again on Nov 9 you posted ----------
Bottom dregs, palladium with a bit of gold.

Plastic tub tare weight, 18.1 grams
Palladium Net, 33.5 grams
Again per the bold print --- 33.5 grams of Pd from LESS then a bucket (so less then 50 pounds)

Sorry - but NOT going to happen - you would be lucky if you got that much Pd from a full ton (2000 pounds) of nothing but HIGH grade boards

Then yesterday you posted -----------
Unrefined palladium with a bit of gold, this will be going to EDI in Ontario.
Again per the bold print (along with pic on scale showing 93.4 grams) from one bucket that MAYBE weighs 50 pounds --- just NOT going to happen

Considering the boards you are processing you will be lucky if there is any Pd at all in that 93.4 grams

And then you say ------------
It appears to me the palladium content on e-waste exceeds the gold content.
FACT - even the highest grade of consumer circuit boards will NEVER contain more Pd then gold

There are a FEW exceptions - but that would be OLD aerospace/military/telecom or OLD soviet stuff --- VERY RARE

I am going to give you some REAL recovery numbers on batches of boards I have done

All of these batches where done by shredding the boards - incinerating the shredded boards - ball milling after incineration - then smelting - then assaying on the smelt metal

All of these batches had at least 30% & up to 50% HIGH grade boards - high grade being RAM, hard drive, finger cards & telecom boards

Side note; - though these batches had more high grade & mid grade they also had some low grade (like 10 -20%)

All of them had at least 10% & up to 30% OLD stuff (mid 1990s & older) which contain much more PMs then modern stuff

in other words ALL of these batches had MUCH higher grade stuff then you are running in your system

These are the batches

415 pounds of CBs (Circuit Boards) metal recovery - Au 1.98 ozt - Ag 3.15 ozt - Pd 5.9 grams - Cu 28.8 pounds

602 pounds of CBs - metal recovery - Au 1.26 ozt - Ag 4.57 ozt - Pd 7.46 grams - Cu 43.4 pounds

948 pounds CBs - metal recovery - Au 2.29 ozt - Ag 6.91 - Pd 15.23 grams - Cu 60.9 pounds

1041 pounds CBs - metal recovery - Au 2.53 ozt - Ag 7.8 ozt - Pd 19.28 grams - Cu 84.3 pounds

1632 pounds CBs - metal recovery - Au 5.22 ozt - Ag 9.18 ozt - Pd 1.01 ozt - Cu 114.3 pounds

Note; - the silver runs "about" 2-3 times higher then gold & the Pd runs "about" 1/4-1/3 of gold

So - considering the VERY low grade material you are running through your system (IMO) you will be LUCKY if you even recover 1 grams of gold (let alone 2 grams) maybe 1 or 2 grams silver & if you are really lucky maybe a "trace" of Pd from the 50 pounds (or less) CBs in your bucket

stoneware - please understand - I am in no way trying to be rude &/or disrespectful --- just trying to give you a reality check here

50 pounds (or less) of very low grade stuff is at best only give you a couple grams of PMs - let alone troy ounces of PMs

Kurt
 
AND - just to add to my last post

The only PM you are going to recover with your system is the gold "plated" on surfaces of the board &/or pins

NO gold from bond wires inside IC chips (maybe a trace from broken chips)

Little or NO silver because the silver is found inside of components - not surfaces

Same with palladium - its found inside components - not on surfaces

All the abrasion in the world is not going scrape PMs off something the PMs are inside of

So MOST of the PMs are still left inside what the abrasion can't get to

Its a system designed to leave MOST of the values behind

It might work if you put nothing but gold plated pins &/or close cut fingers in it

But CBs - even shredded - is going to leave most of the PMs behind

Kurt
 
AND - just to add to my last post

The only PM you are going to recover with your system is the gold "plated" on surfaces of the board &/or pins

NO gold from bond wires inside IC chips (maybe a trace from broken chips)

Little or NO silver because the silver is found inside of components - not surfaces

Same with palladium - its found inside components - not on surfaces

All the abrasion in the world is not going scrape PMs off something the PMs are inside of

So MOST of the PMs are still left inside what the abrasion can't get to

Its a system designed to leave MOST of the values behind

It might work if you put nothing but gold plated pins &/or close cut fingers in it

But CBs - even shredded - is going to leave most of the PMs behind

Kurt
The glaciers did a pretty good job of reshaping the earth.

Using the small hatchet mother boards were depopulated, do you suppose those small surface mounted caps may have survived the beating.

Those that did were incinerated.

As for the Pd with the gold content, figured too much gold so It's in AR. Now waiting on the weather to change. This type of work is done outdoors.

You may recall the concentrates were pr-cleaned of base metals.

Now that you've added your two cents. it's time for you to replicate the process and give us some real data

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AND - just to add to my last post

The only PM you are going to recover with your system is the gold "plated" on surfaces of the board &/or pins

NO gold from bond wires inside IC chips (maybe a trace from broken chips)

Little or NO silver because the silver is found inside of components - not surfaces

Same with palladium - its found inside components - not on surfaces

All the abrasion in the world is not going scrape PMs off something the PMs are inside of

So MOST of the PMs are still left inside what the abrasion can't get to

Its a system designed to leave MOST of the values behind

It might work if you put nothing but gold plated pins &/or close cut fingers in it

But CBs - even shredded - is going to leave most of the PMs behind

Kurt
Kurt, maybe he started with one of those rare PM lined special propane tanks. Then it would make sense.
 
Hi stoneware

As I said yesterday - in no way am I trying to be rude &/or disrespectful

I am simply saying that the expectations you have for PM value recovery with your system are unrealistic - very unrealistic

To clarify - at the same time - I am NOT saying that your system won't recover value - it will

The question is - is the amount of values you can recover with this system worth the cost

Cost = time - energy (electricity) - chems - & dealing with waste

In other words - is the expected recovery worth the above cost

In order to determine that we need to look at the purpose of the system &/or the feed stock intend to be run in the system

So at least as I understand the purpose of your system (and please correct me if I am wrong) it is to recover the values left behind on CBs AFTER you have removed the higher grade components (such as IC chips - fingers - fully plated pin - etc.) as that stuff is processed through other systems/processes

In other words - chase the values left after high grading (depopulation) the boards

So - in order to come up with an expectation of recovery - for the "feed stock" to be run through your system we need to consider that feed stock & how we get to that feed stock

That means we first need to look at the values of CBs as a whole (where the values are on a whole CB) --- we need some sort of base line on expected recovery of values from whole CBs --- we need an example

We will focus on the gold

Yesterday I gave you the example of modern day mother boards --- modern day mother boards on average will give you "about" 3.5 ozt gold per ton --- that is full recovery by way of shred - incinerate - ball mill - smelt the whole CB

That means the full gold recovery of 1 pound modern day mother boards has an expectation of .05 gram gold ---- one mother board weighs about one pound

Now lets "high grade" that mother board (take off the IC chips & fully plated pins) to process by "other" means (bonding wire recovery from chips & gold foil recovery from fully plated pins)

This removes about 2/3 of the value from the boards as that is where most of the value is

That means (after depopulation) you are left with 1/3 the value of the whole board - for your feed stock

1/3 of .05 gram = .016 gram

That means if you run 50 pounds of this feed stock through your system (& got 100% recovery) you would end up with .83 gram 999 refined gold

Lets round that up to 1 gram --- 1 gram gold at current spot = $56.45

So is the cost of your time (several days to shred, mill, sift, water separate, chem work & deal with waste) energy (electric to run shredder, run mill, water pump, hot plate) chem & dealing with waste - is that cost worth it to get to $56.45 of 999 refined gold --- add in Ag & Pd we may get that up to $100 (based on known recovery from 1 ton boards) - so even at $100 - is it worth the cost ?

Even something like high grade telecom boards - about 90% of the gold value is in the IC chips & fully plated pins - so after high grading them (depopulating) - your feed stock is low graded to about 10% of its original whole board value

Stoneware - I do commend you on your build & all of your effort - your build is absolutely awesome - BUT - as a system for the recovery of value - it will ALWAYS be a system that will cost more then values it can possibly recover --- no matter how much you tweak it !!!!

The values in your feed stock (edit to add; - & be profitable) simply are not there

Kurt
 
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Kurt your assuming that I had shred the whole mother board, which is not the case.

The boards were cherry picked, the parts were fed through the shredder to expose the gold and other precious metals.

Abrasion works even the refineries use the method on appropriate material.

Personally I don't care if your a none believer nor do I care if anyone uses the method in the future.

You say the cost of equipment, electricity and waste chemical's make the process prohibitive.

The only waste I have from the milling process is 20 liters of water used to rinse the shred free of values. This water will be recycled in the next batch.

Now that I'm into the acid stage there will be some nasty waste to deal with but that's the nature of the hobby.
 
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