These metal Processor chips have me stumped! Over 18 lbs of them!

[MicheleM]

Is that even possible to do in a practical way?
They are usually way to small and thin.

Yes, I did exactly this with the gold bonding wires attached to CCD/CMOS inside cellphones and laptop, it's even more difficult because the smaller dimensions. For the gold plating HCl and HCl-Cl

 

[J&D]

First of all i would remove the bonding wires manually (using a appropriate container) , they are about 90 pct of all gold. After that I would break each single "square" and i would put them in HCl, in my opinion too much Al for NaOH

Like scrape them off? Use a chisel or something? That makes sense, I would assume these are where my value is for the most part. Just scrape scrape scrape scrape

 

[J&D]

First of all i would remove the bonding wires manually (using a appropriate container) , they are about 90 pct of all gold. After that I would break each single "square" and i would put them in HCl, in my opinion too much Al for NaOH

I see the benefit in this. Thank you for sharing that pic

 

[J&D]

Yes, I did exactly this with the gold bonding wires attached to CCD/CMOS inside cellphones and laptop, it's even more difficult because the smaller dimensions. For the gold plating HCl and HCl-Cl

Here is the result of scraping two of these chips.....I guess I know what I'll be doing all week!
I think it is funny, I was looking for a complex solution, and just needed to be reminded, "you could just try scraping it off!"
Thx for the tip, I think I'm gna go with this

 

[MicheleM]

Great, absolutely beautiful. At the end do not forget to take look at each item with a good lens to be sure that no wire is left

 

[BlackLabel]

Hi Jason,

First of all: Great haul - congrats!

I can't see it on your photos, but the round golden dots must be attached to a kind of epoxy board (they must be isolated from the aluminum part).
Did you try to split the epoxy from the aluminum by using a sharp cutter blade?

 

[user 69385]

Hi all. My name is Jason. Earlier this week I found about 18 lbs of manufacturer scrap processor chips. Still in strips of 4-6. Hundreds of strips of 4-6. They are beautiful. Packed with gold bonding wires and all, exposed already.
BUT the strips and the wafer the chips are on is made of aluminum.
I have never heard of aluminum wafers for a chip. I have no idea how best to process these!
I can recover the gold from printed circuit boards, ceramic chips, etc. But those materials are not on AL.....all of my acids will just work against me dealing with aluminum, right?
I am kind of stumped. I'm going to include some pics of this material. If anyone has an idea how best to process these, I would be very grateful to hear it. I have all of my acids, glassware, 10 years of experience, a proper workshop, fume hood, etc....I just wasn't expecting this curve ball!
Metal chips.....and so so many of them!
In the following pics, you can see a yardstick for reference to the scale of these. Its over a cubic yard of these buggers laid out, and there was probably 4 pounds left in a bin, I just got tired of making the cube there were so many

There is a way to get around this using concentrated acetic acid which appears to only attack the gold. There is a link here to the article which is 6 years old. The green way to extract gold

 

[J&D]

Hi Jason,

First of all: Great haul - congrats!

I can't see it on your photos, but the round golden dots must be attached to a kind of epoxy board (they must be isolated from the aluminum part).
Did you try to split the epoxy from the aluminum by using a sharp cutter blade?

Hey there, when I was scraping at a couple of these, there is like a resin or epoxy stuff that comes off, a very thin coat of clear, didn't realize it was there. But it is over all of the bga dots, yes. Not sure what to do about that either!

 

[J&D]

There is a way to get around this using concentrated acetic acid which appears to only attack the gold. There is a link here to the article which is 6 years old. The green way to extract gold

Thank u yes I've also heard of acetic acid method. Never tried it. But I will check this link out and see if it applies to this material possibly. Thx for the suggestion

 

[user 69385]

Thank u yes I've also heard of acetic acid method. Never tried it. But I will check this link out and see if it applies to this material possibly. Thx for the suggestion

Many on here doubt this works, so I have emailed the person and asked if he would expand a little.

 

[GoIdman]

Hey there, when I was scraping at a couple of these, there is like a resin or epoxy stuff that comes off, a very thin coat of clear, didn't realize it was there. But it is over all of the bga dots, yes. Not sure what to do about that either!

Hi,

The thin layer that you think is epoxy, is basically a thin layer of flux (alcohol mixed with pine resin and some chemical material) so when the pins or balls are soldered they stick better. You can wash that away with isopropyl alcohol ol plain sanitary alcohol. It will remove it almost instantly.

That is an amazing find, congrats and good luck.

Pete

 

[nwinther]

I don't know what AR does to Aluminum though.

I recently read an aside on a Danish website (can't find it now, though), that since AR doesn't attack aluminium it was once used to clean the insides of aluminium boilers at power plants or somesuch.

Other websites clearly state that AR does indeed attack aluminium.

 

[Yggdrasil]

There is a way to get around this using concentrated acetic acid which appears to only attack the gold. There is a link here to the article which is 6 years old. The green way to extract gold

Acetic acid alone do not dissolve gold. Same with HCl or Nitric, but when you add Oxidizer it works and as one see here they use oxidizer.
Dissolved metal salts are toxic no matter how you dissolve them.
Lead acetate is very toxic and taste like sugar, hence the popular name "Lead sugar".

 

[Yggdrasil]

I recently read an aside on a Danish website (can't find it now, though), that since AR doesn't attack aluminium it was once used to clean the insides of aluminium boilers at power plants or somesuch.

Other websites clearly state that AR does indeed attack aluminium.

Thanks nwinther, one can easy assume it has to do with alloy then.
Edit to add:
On after thought, can they use Aluminum pressure tanks for boilers?
The flame side is highly corrosive due to flame oxidision, the boiler tank itself will have to withstand high pressure.
I’m not sure Aluminium is up to this kind if abuse.
I’d expect some kind of Titanium or special alloy for boilers.

 

[J&D]

Hi,

The thin layer that you think is epoxy, is basically a thin layer of flux (alcohol mixed with pine resin and some chemical material) so when the pins or balls are soldered they stick better. You can wash that away with isopropyl alcohol ol plain sanitary alcohol. It will remove it almost instantly.

That is an amazing find, congrats and good luck.

Pete

Thx Pete, I will def do that. Good to know. Jason

 

[orvi]

Nitric do not dissolve Gold or Aluminum.
I don't know what AR does to Aluminum though.
The Sodium Hydroxide route may be the cheapest.
Just add 200g of powder to 1L of water. this will give 17% or so solution.
Strip the majority of the Al from the items first, it will save time and cost.

Aluminium dissappear in regular warm AR like nothing, evolving some funky nitrogen oxides as nitrous oxide. Very reactive and reaction is extremely exothermic, as practically all dissolutions of aluminium. Wasteful to use AR, HCL alone is more than sufficient.

Does it need to be heated? Or does it produce it's own heat?

Sodium hydroxide dissolution in water is very exothermic - if you ever unclogged the drain by pouring the "drain cleaner white grains" according to manual and pour hot water onto it
Prepare 20% solution by taking 4 parts of water, and add 1 part of NaOH (weight) slowly with stirring. Dissolution is quick, and you are left with warm solution ready to use. Wear thick rubber gloves also covering partly your forearms. Goggles or better face shield is A MUST - hot lye in the eye... I experienced that real life. Few seconds and you are blind for life. But as long as it does not get onto skin or worse eyes, you will be perfectly fine. Be also aware of "mist" as you dissolve NaOH in water, and also reacting anything in NaOH - "mist" or aerosol, containing that NaOH is emitted from the vessel. Not severly bad, but it is annoyingly irritating to the nose and lungs, certainly not healthy and comfy to breath it
Aluminium reaction with lye/hydroxide sometimes take few seconds or minutes to kickstart, but then, it become very very vigorous, and lots of heat is evolved during the process. Few dozens grams of Al reacting with lye can easily heat up the small bucket of solution to the boiling point. Be aware of this fact, and put them one by one to the solution and observe the reaction.
Be careful and try it out on small scale before scaling up. There wouldn´t be any terribly toxic substances evolved during the process, but as with any caustics, great caution is a must chemistry never do anything that it shouldn´t only we are unprepared.

 

[J&D]

Aluminium dissappear in regular warm AR like nothing, evolving some funky nitrogen oxides as nitrous oxide. Very reactive and reaction is extremely exothermic, as practically all dissolutions of aluminium. Wasteful to use AR, HCL alone is more than sufficient.

Sodium hydroxide dissolution in water is very exothermic - if you ever unclogged the drain by pouring the "drain cleaner white grains" according to manual and pour hot water onto it
Prepare 20% solution by taking 4 parts of water, and add 1 part of NaOH (weight) slowly with stirring. Dissolution is quick, and you are left with warm solution ready to use. Wear thick rubber gloves also covering partly your forearms. Goggles or better face shield is A MUST - hot lye in the eye... I experienced that real life. Few seconds and you are blind for life. But as long as it does not get onto skin or worse eyes, you will be perfectly fine. Be also aware of "mist" as you dissolve NaOH in water, and also reacting anything in NaOH - "mist" or aerosol, containing that NaOH is emitted from the vessel. Not severly bad, but it is annoyingly irritating to the nose and lungs, certainly not healthy and comfy to breath it
Aluminium reaction with lye/hydroxide sometimes take few seconds or minutes to kickstart, but then, it become very very vigorous, and lots of heat is evolved during the process. Few dozens grams of Al reacting with lye can easily heat up the small bucket of solution to the boiling point. Be aware of this fact, and put them one by one to the solution and observe the reaction.
Be careful and try it out on small scale before scaling up. There wouldn´t be any terribly toxic substances evolved during the process, but as with any caustics, great caution is a must chemistry never do anything that it shouldn´t only we are unprepared.

Wow, I will def take those precautions! I have a good full face mask and some elbow length rubbers I will put on. Thx for the tips. Currently waiting on my sodium hydroxide granules.....Chemistry never does anything it shouldnt, we only are unprepared! I like that! so true

 

[J&D]

Wow, I will def take those precautions! I have a good full face mask and some elbow length rubbers I will put on. Thx for the tips. Currently waiting on my sodium hydroxide granules.....Chemistry never does anything it shouldnt, we only are unprepared! I like that! so true

Aluminium dissappear in regular warm AR like nothing, evolving some funky nitrogen oxides as nitrous oxide. Very reactive and reaction is extremely exothermic, as practically all dissolutions of aluminium. Wasteful to use AR, HCL alone is more than sufficient.

Sodium hydroxide dissolution in water is very exothermic - if you ever unclogged the drain by pouring the "drain cleaner white grains" according to manual and pour hot water onto it
Prepare 20% solution by taking 4 parts of water, and add 1 part of NaOH (weight) slowly with stirring. Dissolution is quick, and you are left with warm solution ready to use. Wear thick rubber gloves also covering partly your forearms. Goggles or better face shield is A MUST - hot lye in the eye... I experienced that real life. Few seconds and you are blind for life. But as long as it does not get onto skin or worse eyes, you will be perfectly fine. Be also aware of "mist" as you dissolve NaOH in water, and also reacting anything in NaOH - "mist" or aerosol, containing that NaOH is emitted from the vessel. Not severly bad, but it is annoyingly irritating to the nose and lungs, certainly not healthy and comfy to breath it
Aluminium reaction with lye/hydroxide sometimes take few seconds or minutes to kickstart, but then, it become very very vigorous, and lots of heat is evolved during the process. Few dozens grams of Al reacting with lye can easily heat up the small bucket of solution to the boiling point. Be aware of this fact, and put them one by one to the solution and observe the reaction.
Be careful and try it out on small scale before scaling up. There wouldn´t be any terribly toxic substances evolved during the process, but as with any caustics, great caution is a must chemistry never do anything that it shouldn´t only we are unprepared.

with such a vigorous reaction, would you say the choice of vessel be a beaker or a flask?>I have large ones of each, just wondering, which best? thx

 

[orvi]

with such a vigorous reaction, would you say the choice of vessel be a beaker or a flask?>I have large ones of each, just wondering, which best? thx

Glass is fine, but as you scale up to the big lot, PP bucket will also serve good. For tests, definitely beakers. If you build up confidence, polypropylene bucket is also OK, as it is resistant to hydroxide.

 

[BlackLabel]

There wouldn´t be any terribly toxic substances evolved during the process, but as with any caustics, great caution is a must chemistry never do anything that it shouldn´t only we are unprepared.

Maybe "caution" comes from "caustic"…