AP solution for removing ic chips legs

[joheleh]

Hi guys, I have a batch of 4,5kg of plastic ic chips.
I’m trying to remove legs with a bath of AP solution made of 3lt of HCl and 1H2O2
I know most of the legs are Kovar but I tried anyway, I added some copper wire to the solution hoping to form some Cu2.
Now, it’s been 2 weeks (with no bubbler) and those are the results.
To me seen the reaction stopped but I don’t know.
In your opinion should I wait?

 

[Yggdrasil]

Add bubbler. A few ml of Peroxide is enough, then bubbler.

 

[joheleh]

Add bubbler. A few ml of Peroxide is enough, then bubbler.

The chips are really packed…maybe I could tie a rubber tube to a stick…and put it at the bottom…

 

[Yggdrasil]

Or take them out put in the hose and put them back in again.

 

[kurtak]

Why in the world are you wasting acid & creating acidic waste to dissolve the legs away on the outside of the chips ?

I ask because it makes NO sense to do this !!!

You are gaining NOTHING doing this other then creating UN-NEEDED chemical waste !!!

Why ?

Because the legs on the "outside" of the chip are only a "small" part of the lead frame that goes inside of the chips

SO - when you go to incinerate the chips - to get to the (gold) bond wires - you are still going to end up with MOST of that lead frame base metal in the carbon/ash after incineration

That means you still have to separate all the lead frame base metal "inside" the chips from the carbon/ash (after incineration) with a magnet &/or sifting

To put it in perspective --- the legs on the outside of the chips is only "about 10 - 15% of the lead frame - the other 85 - 90% of the lead frame is "inside" the chips

It makes absolutely NO sense to waste time - waste chemicals & create chemical waste to eliminate a VERY small part of the base metal --- when you "still" have to remove "the rest" of the lead frame from the carbon/ash after incineration anyway !!!

I don't know where you got this idea but it is a TOTAL waste of time & chems when you still have to remove the vast majority of those very same lead frames form the carbon/ash after incineration anyway

Kurt

 

[Martijn]

What Kurt said.

P.s. you don't have AP. You have ferric chloride imo.
All copper is clinging to the (iron)base metal legs. That's why the reaction 'stopped'
All reachable copper is pretty much dissolved.

 

[MicheleM]

Why people do things and only then ask for advices instead to do the opposite?

 

[joheleh]

Wait…please don’t be so rude…
First: at the end of the process my intention was to collect the waste AP solution for next projects.
Second: after incineration I will dissolve magnetic material in nitric trying to recovery some PM from it and I was trying to eliminate all the base metals possible just to optimize the quantity of nitric in the next step.
…guys there is no reason to be so mean..

 

[MicheleM]

@joheleh sorry for the rudeness, anyway, AP solution or CuCl2 (aq) works at his best without base metal contaminants, i mean Fe Cl 3 and Cu Cl2 are good ions in solution all the other metals that come from the IC legs will reduce the etching properties and create more waste. Nitric acid on the remaining magnetic material is not the best option, unless you are able to obtain nitric at a very cheap price

 

[joheleh]

@joheleh sorry for the rudeness, anyway, AP solution or CuCl2 (aq) works at his best without base metal contaminants, i mean Fe Cl 3 and Cu Cl2 are good ions in solution all the other metals that come from the IC legs will reduce the etching properties and create more waste. Nitric acid on the remaining magnetic material is not the best option, unless you are able to obtain nitric at a very cheap price

Thanks, what process you suggest to eliminates base metals from the magnetic material?

 

[Martijn]

A magnet?

 

[joheleh]

A magnet?

A magnet….listen, I have to recover precious metals from the magnetic material, obviously I’ll SEPARATE it from the dust with a magnet, I was asking another thing…how to ELIMINATE base metals from magnetic material without nitric…

 

[Yggdrasil]

A magnet….listen, I have to recover precious metals from the magnetic material, obviously I’ll SEPARATE it from the dust with a magnet, I was asking another thing…how to ELIMINATE base metals from magnetic material without nitric…

In this case the base metals are the magentics, so its not possible.

 

[kurtak]

Wait…please don’t be so rude…

…guys there is no reason to be so mean..

No one is being rude or mean !!!

you asked for advice - we (not just me) are providing you with advice

Just because the advice you are receiving is different then what you were expecting certainly doesn't mean we are being rude or mean - it only means - "you took it that way" - because you got answers different then you expected

First: at the end of the process my intention was to collect the waste AP solution for next projects.

Thats not going to work the way you "think" its going to work !!!

Second: after incineration I will dissolve magnetic material in nitric trying to recovery some PM from it and I was trying to eliminate all the base metals possible just to optimize the quantity of nitric in the next step.

That most certainly is not going to work like you think it is going to work !!!

You have a plan (to process IC chips) - but its a bad plan !!!

Why ?

because it's going to create A LOT of chemical waste - that you do not need to create - in order to recover (around) 4 - 8 grams of gold from your 4.5 Kg of chips (depending on the "mix" of different "types" of chips in that 4.5 Kg)

There are better ways to get that gold - then the way you are planning !!!

So my question is ---------

Are you "actually" asking/looking for advice to recover that gold --- or are you just looking for "confirmation" that you have a good plan

For what it is worth - I used to process 500 - 600 pounds of IC chips per year - so I am more then glad to help you with the process

Other wise - you already have a plan & I wish you best of luck with your plan

Kurt

 

[MicheleM]

There is a very limited amount of PM plated onto magnetic leadframe inside IC chips, anyway CuCl2 is very slow but works fine (but in time base metals are going to accumulate), water with NaCl and HCl is ultra-slow (there is a thread : "iron wire inside IC chips" or something like that) but in the end it works.

 

[Maget]

Instead of burning I would crush them with a special machine like coffee grinding ones, then would do the chemistry on that powder.
I remember I was hammering such IC's and other types and extracting the insides of them, of course it was a small batch, based on hammering I know some grinding machine can break them without burning.

 

[kurtak]

A magnet….listen, I have to recover precious metals from the magnetic material, obviously I’ll SEPARATE it from the dust with a magnet, I was asking another thing…how to ELIMINATE base metals from magnetic material without nitric…

Some where along the line someone has given you VERY BAD advise (likely from You Tube)

Like I said - I used to process 500 - 600 pounds of IC chips per year - so --------

Do you want my help ?

Or not ?

Kurt

 

[joheleh]

Some where along the line someone has given you VERY BAD advise (likely from You Tube)

Like I said - I used to process 500 - 600 pounds of IC chips per year - so --------

Do you want my help ?

Or not ?

Kurt

Sure! Your help would be very appreciate, in the end your answers are supported by your huge experience, and I’m glad to be in this forum with people like you.
Yes, I would like to know how to process the IC’s after burning them…
I made enough mistakes, but i try to learn

 

[Shark]

To go back to the original post. Three parts hydrochloric to one part hydrogen peroxide DOES NOT make copper(ll)chloride. Hydrochloric acid and copper oxide will. Where is everyone getting this three to one formula after all these years of GRF trying do away with it? Rant over……. Back to Kurt.

 

[FrugalRefiner]

Unfortunately, it comes from the early posts on the forum, perpetuated by repetition and its inclusion in Ralph's forum handbooks, let alone all the other instances on the internet and youtube.

Dave