A video posted by a member for refining DIP's Let's discuss this!

[4metals]

Refining DIP's

This video is made by Trinity Gold. I do like some of his techniques but question others. I think this video will give us an opportunity to put everyone's life's experiences together to discuss what he did and why. And propose any changes you would make and we can hash those out as well.

In the end, I will summarize this thread to, hopefully, have a detailed methodology for all to follow when needed. Then the summary will go into the library so we can find it when we need it!

So, to avoid too much moderator BS, who wants to go first? Have at it!

 

[Darkthirty]

Refining DIP's

This video is made by Trinity Gold. I do like some of his techniques but question others. I think this video will give us an opportunity to put everyone's life's experiences together to discuss what he did and why. And propose any changes you would make and we can hash those out as well.

In the end, I will summarize this thread to, hopefully, have a detailed methodology for all to follow when needed. Then the summary will go into the library so we can find it when we need it!

So, to avoid too much moderator BS, who wants to go first? Have at it!

Obviously OSHA approved pajamas and slippers.

 

[andu]

Obviously OSHA approved pajamas and slippers.

You cracked me up with that one.

I always have the feeling he loses gold with the incineration, grinding and washing.

 

[Yggdrasil]

You cracked me up with that one.

I always have the feeling he loses gold with the incineration, grinding and washing.

Most of these videos has no educational intent, only clicks and views and as such, losses are of no concern.

 

[Yggdrasil]

I have now watched this video.
What can I say, there was a few clever adaptations and some very strange things too.
His funnels was clever and cheap.
Lab hygiene was, I do not know what to call it, but mostly for show I think.
The powdered chips should have been roasted once more.
No Urea used on the Silver Chloride as the OP who inspired this thread claimed.
Way to much handling and back and fort with the precipitation.
And what was the point of the Sulfuric acid in the final precipitation of the Gold?
And where did that Silver come from?
There should not be that much Silver on the legs, should there?

 

[Yggdrasil]

It seem I was mistaken, I referred to a different video not from Trinity.
And indeed he says he uses Urea to transform Silver Chloride to metal.
I don't know if that is possible at all.
Poor lab techniques there, sloppy actually.

Edit to add.
This one: Oxidize silver chloride using urea

 

[macfixer01]

I wonder how much other non-IC junk was in the pile? Did you all notice the Pulse ethernet transformer that was laying on top of the pile of chips at around the 10 to 12 second mark? They’re very easy to spot since they’re much thicker than a dip IC. The pins are also more closely spaced (finer pitch), not the standard 1/10 inch spacing. The sulfuric acid would’ve been used to drop any lead content as insoluble lead sulfate. He added it too early though, before the AR had a chance to dissolve the gold. It actually looks like the captions are wrong and he added the HCL, then sulfuric acid, then nitric acid? Because it was only when he poured in the last liquid that the brown fumes began.

 

[Shark]

Many YouTube videos have the right chemicals, but often out of order. I have seen a few that add the sulfuric acid to remove lead after filtering the AR only to jump right to the precipitation. Many videos do this at times. It is one of the things I use to decide if that person is worth my time to watch more of their videos, although at times a few will make these mistakes early in their refining and still produce better content later.

These days when I watch a refining video I am researching more than just the basics, such as advanced pgm’s or dealing with unusual base metals like tungsten.

 

[Martijn]

I think the reaction takes off after adding sulfuric at last, because of the temperature rise by the sulfuric.
He does this twice in the video. Heating with sulfuric.
Neat trick.

 

[Martijn]

I always have the feeling he loses gold with the incineration, grinding and washing.

There could have been bonding wires still in carbon, and some gold chloride was probably trapped in the carbon after AR?

 

[orvi]

Fact that you end up with gold bead in the end does not neccessarily mean you have done it efficiently.
Liquid waste is obviously not a concern for him in his country, as he will create more than 20+ liters of various waste solutions from just 2 kg of material. Which can be processed with little to no acids in comparably good yield.
What I don´t like (aside from all of the safety and enviromental issues):

1. Nitric acid etch of legs. This can lead to very ugly consequences with some material. He shows how tame the reaction is and solution is blue in the end (copper material). This do not necessarily mean you would encounter the same behaviour. Many DIPs have ferrous legs. And iron does only two things in diluted nitric - absolutely nothing, or absolutely go nuts and react violently.

2. Filtering gold dust through cotton. With several liters of solution, and supposedly below 1g of gold, you have such dilute solution, that gold dust created is nearly nanodust. Swirling it around and pouring through cotton will filter just fraction of precipitated gold. Or I am lame and never achieved good filtration efficiency when filtering micro gold through cotton. Or he has some magic cotton I don´t know.

3. Washing the carbon/ashes from incineration. Maybe guy precisely know if these ICs containg gold bonding wires or not (could be the case). But if the answer is yes, then there is quite a chance you will lose gold by following this procedure of washing - without the use of surfactant. Gold is hydrophobic and small particles float on the water with no issue.

4. Incomplete incineration and lots of leftover carbon will retain the gold when dissolving in AR later.

5. I do not like the use of PET water bottle for collecting the filtrates. As a serious safety concern, because PET does not withstand HCl or AR very well. Maybe for some short time, but it become dangerously crumbly and fragile. Maybe in his country, these big office bottle reservoirs are made from better and more durable plastic than PET, but I seriously doubt it.

6. Dilutions in which he always work are insane. But there is a point in it. Maybe unintentionally, maybe he knows, diluting all of the solutions cause lowering of redox if some unreacted nitric is present, thus preventing rapid gold redissolution - if you add urea to them. Urea will kill remains of N(III) residues in solution quicker than gold can react in such dilution and temperature.
But I still does not like the volumes. If you pour all of the waste down the river, than there is no concern about ammount of waste... I get it.

On the other hand, I like his skill in handling and pouring/transferring the liquids. Looks like he has done it a lot. But at least, he invested into gloves As supposedly content for making revenue from YT, still one of the better ones around
And also trick with sulfuric acid, which he basically use just to heat the solution Not a perfect one, as ton of HCl evaporates by doing this, but nice trick to impress viewers.

 

[4metals]

Processing the 2 kg of material yielded the following.

Gold 0.91 grams. At current prices Gold is worth $58.93 per gram. Making 0.91 grams worth $53.62
Silver 4.55 grams At current prices Silver is worth 69¢ per gram. Making 4.55 grams worth $3.13
Total value of PM’s $56.75. We are not here to discuss how much of this value you will forfeit when you sell your metal.

Less cost of chemicals and a proper attempt at waste treatment, there isn’t much, if any, profit for a hobby refiner in the USA. (Given non-commercial nitric rates)

All of that aside the way I would handle this material is different. First and foremost, I would incinerate, grind (and I really like that little grinder, I would like to know where to get one) and sieve the powders first. They appear to burn rather completely with a torch for small lots as was done in the video. After crushing they can easily be passed through a sieve dry and if an additional second crush is required to knock off the ash it can be done. To start I would choose a 40- mesh screen (US standard sieve series) and pass everything through the screen. The powder was assumed to be valueless by the maker of the video, for now I would assume the same as long as the fines do not show any pieces of wire or metal.

If nothing else, the volume taken up by the material too big to pass through the screen is considerably less than the starting volume. Now there are two possible paths.

I would choose the smelt and copper electrolytic cell path, which will involve adding copper metal but in the long run give me back all of the copper and leave the PM’s in the slimes. These techniques have been discussed here on the forum in a smelting thread and an electrolytic copper refining thread.

The second path, the one the video refiner choose, is the chemical refining method. First, I would magnetically separate the magnetic legs from the rest of the oversize to keep the magnetic legs (possibly Silver plated or not) apart from the metals which were encapsulated inside the IC. These magnetic parts will be put aside for treatment later or not. Remember the original lot only contained a bit over $3 in silver

Having removed most of the mass by screening and magnetic separation we now have a much smaller pile to process in acid. Smaller pile means less acid and greater economy. There seems to be different opinions as to whether or not there is silver inside the IC’s, surely the videographer did not consider silver inside the IC. For this reason, I would digest the material in aqua regia. Assuming most of the material is digested, I would de-nox with sulfamic acid, chill, and filter the acid for gold precipitation. The gold is dropped, rinsed well and dried. The waste acid is always tested and cemented with copper for potential Palladium content.

Now attention is turned to the insolubles after aqua regia digestion, keeping an eye out for silver chloride to determine if there was silver internally in the IC’s. A wash with very hot water to dissolve any lead chloride. This is followed by dissolving any “potential silver chloride” in ammonia to dissolve the silver chloride which is dropped with Hydrochloric acid and stored wet and in the dark with any other silver chlorides until I have enough to process.

I would process this material in one, or two, kilogram quantities until I have a feel for how consistent the IC scrap is. Then I would bump up my processing based on larger digestions. Something about working a day or two for 0.91 grams of gold is depressing. Collecting the oversize fractions as described above and holding them until a more respectable quantity of the elusive yellow metal can be had, leads to a less depressing end of a refiner’s day.

Finally, I would blend and sample the ash which passed through the screen to determine if it is actually payable when collected in drum quantities. Larger refiners always collect the fines and ship them as a low-grade material for recovery on assay.

 

[kurtak]

4metals & orvi --- AWESOME review of this video !!!

I have wanted to post a review as well but just have not had time as it would take a very long post if not a couple of long posts (keeping in mind that I used to process anywhere from 300 - 500 pounds of chips per year for 5 or 6 years)

There is no question that he lost values in his process (both gold & silver) - something very common in most such youtube videos - meaning just because you recover values does not mean you did so effectively --- but you get to tell your viewers - "look at what I did"

Just in the silver recovery - by treating the chips with nitric before incineration he lost about (plus/minus) half of his silver

That is because he only recovered the silver (plating) from the lead frame legs on the outside of the chips

When they make the chips they silver plate the "entire" copper sheet from which the lead frames are cut (I believe they first laser cut the lead frames in the copper sheet then silver plate them) - they then assemble the lead frame, die, bond wires & then incase that assembly in epoxy --- so there is silver plating on the lead frame "inside" the epoxy housing of the chip (to the best of my knowledge/experience they do not silver plate Kovar lead frames)

Therefore - that silver plating on the lead frames "inside" the chips was lost (as silver chloride) when he went to AR (for gold recovery) after washing away carbon after incineration/milling

All I have time for today

Kurt

 

[rusti2]

They should have done an oxidizing calcination that eliminated all the organic matter and carbon residues, then the leaching with nitric, washing and finally with aqua regia, abused the use of chemical reagents in general, the same reactions could have been done with quantities much smaller than those used, the excess of sulfuric acid produces an exothermic reaction that initiates the oxidation of gold by the aqua regia, they discarded absolutely all the grinding dust without having verified the presence of precious metals through a simple test on a small representative sample

 

[Brett Novak]

Kurt is correct - I have done it both ways pre-dissolving and post-dissolving from incineration.

Also - Depending on the torch setup and how long you burn for (which, FYI make sure you are WELL exhausted since you are burning plastic LOL) you can actually recover gold and silver in a single step as they will melt out. Problem is, you get everything else too, but it's one less step.

Just what I have found (I use a big steel wok for incinerating) if you just use propane, you end up melting out the silver and nickel into beads and are left with the bond wires (gold) which then go in the nitric and AR runs.

If you use MAPP - it tends to melt everything together, so you have to get the nickel out

if you use a crucible in a furnace it makes a huge mess

it's really a crapshoot unless you KNOW what is inside the devices. As I have mentioned, it's not all silver and gold. Some could be copper plated paddles (the thing kurt mentioned on the inside of the pacakge that the bond wires attach to) some are silver. Usually you will find Kovar and or nickel as well, and we all know how much fun that is.

I still have to send Kurt his care package

 

[4metals]

it's really a crapshoot unless you KNOW what is inside the devices.

Commercial refiners don’t have either the time, the knowledge, or the inclination to separate every piece by exact part type. That is more in line with smaller processors or hobby refiners.

That’s why I prefer the smelt and electro refining of the copper, because the smelt takes care of anything that can be oxidized out of the melt and the copper goes to the cathode to make nice electrolytically pure copper and the PM’s report to the slime.

The sulfuric cell really stretches the acid usage as a lot of copper (properly smelted) can be processed with relatively little acid. The only real processing that generates acid waste from aqua regia is the cleaning up and refining the slimes.

Surprisingly this can be accomplished with a small gas furnace, a small copper cell, and a hood for the aqua regia work. I believe Shark can attest to that fact!

 

[Shark]

Surprisingly this can be accomplished with a small gas furnace, a small copper cell, and a hood for the aqua regia work. I believe Shark can attest to that fact!

I sure can. In fact I still play with that same tiny furnace, and very often a one gallon cell, or larger at times. I did have to remake the lid and add a puck to hold the crucible but it still works. It amazes me how many people want to run a silver cell but ignore a copper cell.

 

[Martijn]

Commercial refiners don’t have either the time, the knowledge, or the inclination to separate every piece by exact part type. That is more in line with smaller processors or hobby refiners.

That’s why I prefer the smelt and electro refining of the copper, because the smelt takes care of anything that can be oxidized out of the melt and the copper goes to the cathode to make nice electrolytically pure copper and the PM’s report to the slime.

The sulfuric cell really stretches the acid usage as a lot of copper (properly smelted) can be processed with relatively little acid. The only real processing that generates acid waste from aqua regia is the cleaning up and refining the slimes.

Surprisingly this can be accomplished with a small gas furnace, a small copper cell, and a hood for the aqua regia work. I believe Shark can attest to that fact!

I actually run stripped copper parts straight in a copper cel. Even gold and platina plated jewelry goes in without even melting. Foils and dust are collected in an anode bag. And black used dilute sulfuric from the stripping cell clears up real nice.
Ready to reuse electrolyte.

I love the copper cel! And electrolysis. I run four types. The fifth soon for recycling the purified copper sulfate.

So I agree with 4 metals, some parts can do without smelting. Brass does foul the anode bag and electrolyte in time.

The advantage of running high current in dilute electrolyte (spent sulfuric cell wash water) is that it gives fine powder copper to perfectly mix with a smelt flux as collector.

Or as i do, let it oxidize in a wet filter to rinse with spent electrolyte and convert the free sulfuric in to copper sulfate, purify by crystallization and electrowin the copper and sulfuric acid back out.
I'm hoping to get close to concentrated by adding dry pure CuSO4 crystals to a small cell and using a platinum anode.

Acids are hard to get these days. So anything you can reuse is a hobbyists friend.

 

[rusti2]

I sure can. In fact I still play with that same tiny furnace, and very often a one gallon cell, or larger at times. I did have to remake the lid and add a puck to hold the crucible but it still works. It amazes me how many people want to run a silver cell but ignore a copper cell.

Very interesting, do the impurities of the base metals in the molten anode interfere with the electrolysis? What is the approximate copper content of the anode?

 

[4metals]

Some time ago we started a smelting thread you can find here.
It describes how different fluxing combinations will oxidize the base metals into the slag leaving copper and precious metals behind to cast into anodes.

This part is strictly done in a melt furnace with fluxes and generates no acid waste. The smelting also benefits from the ability to run individual customer jobs in a smelt and quantify the PM content for payment.

then proceed to the electrolytic copper cell here.