Gold recovery need alil help

[Papi980]

:shock: :| :| :| So i did what i could as far as following the process a/p method but im confused as i haven't seen this in what i seen and tried my best to read thru i probably missed it in c. k. Hoke book i have also been halfway looking for videos that can answer but i have found nothing...that being said . yea a/p method, one of three runs i got dark brown yellow slightly mixture at the end. By the way i should tell that all my run through ended with letting mix settle for long time, pouring off for reuse. than dilute and siphon repeating until i had no (or little) acid but only the stuff that settled at the bottom. i know some is solder mask the green bits ,someone had mentioned cementing out copper or something? im just confused and ive devoted my life to going out and picking for ewaste the past 2 years (to the level of the scrap yard offering me a job spot which i so happily took) so i dont wanna screw myself out of much needed money it was very hard to stay on track mentally to keep up with reading the book i did try pretty consistently so what do i do next all i got is a ton of this grey sludge which from what i seen while diluting looked like a webbing of tiny tiny gold specks but when i kept adding to it the more i got it just got super thick im just stuck would like a helping hand have been buying boards everyday when i find cool new stuff at work from xray machines dated in the 50s to precise metal work related programmable machines like robots to city telecom stuff i have no clue what next

 

[nickvc]

Welcome to the forum.
I’m no expert on AP so I may be giving the wrong advice but I’d try a small sample of that residue in HCl and see if it dissolves, if that fails again take a small sample filter it dry and then incinerate, once cool again try in HCl.
There may well be better advice so wait a little while till one of the members who use this process regularly chimes in to either confirm or reject this advice.

 

[Martijn]

As far as i know the cupric chloride leach or AP process is not described by Hoke.


Nickv's advice is good.


The brown color probably came from the copper 1 chloride not being converted to copper 2 chloride by HCL and air.
AP should be bright green.

Below a picture of the different levels of copper 1 chloride in solution.


Once the solution gets saturated with th CuCl₁ it precipitates out as white slimy stuff.
The green color in your picture is probably a bit of copper 2 chloride in soluition. It gets blue when its more dilute.

Add HCL and give it some time and air to dissolve.

Filter the gold and plastic out when all is dissolved and you will have fresh AP to reuse.
Only add HCL when you see the color of the AP get darker.

A file explaining the copper chloride leach:
View attachment cupric chloride etch.pdf

Martijn.

 

[Papi980]

Update dont mind ghettorig heat method and burner but I added the HCL and I've been waiting just about an hour its like a puke garbage green it's staying pretty much the same color but im gonna guess bubbling because I put dish soap in there to try and make the gold sink faster thats what this guy on youtube had posted a video on atleast i guess i need to wash it more this was back when i did the three runs 2 were with the soap irdk i try lookin up stuff get broken ad filled junk

 

[Martijn]

A touch of dish soap is used to break surface tension of clean water when panning tiny gold that sticks to the surface. Not to be used in AP!!!

You just introduced organics to inorganic chemistry...
The HCl will react with the soap and form a stearic acid precipitate, which is only slightly soluble in water.
All other possible reactions that can take place with the salts in solution are unknown to me.

Based on your actions, I think you need to stop experimenting and first get some experience on test tube scale!!
The best option for that mess you have made is to put it aside and study.

If you want to know how to proceed with a mess, you test a small bit to see what happens, and only if the result is satisfactory, apply it to the whole batch. Now you're just making things worse.
I would suggest rinsing the slimes several times in a filter with hot water to get the soap out and treat the AP and rinse water as waste. Don't use it again. It will take a long time to rinse. An air bubbler in the rinse water will indicate if there is any soap left I guess..
You will be left over with a filter full of slimes, foils and trash and to reintroduce to clean AP.

Of course you will first test a small bit in a test tube to see what a bit of HCL does. And give it 'some' time. More than one hour. This can take a day or more. Watch and observe. Gently stir or shake occasionally. It takes a small abundance of HCL to convert the copper 1 chloride to copper 2 chloride. This reaction requires oxygen. So air is the time limiting factor here. If you use no bubbler, it will still convert, but to the air at the surface. Taking more time. Adding more HCL will not speed things up if oxygen is limited.

I hold my air hose down with a stainless steel nut or piece of SS tubing tightly fitting over the end of the hose.

Martijn.

 

[Papi980]

Also question @martin how do you suggest to filter bc coffee filters even folded or a few stacked still let through the tiny gold bits into the other side what should i order to (in advance im sorry i cant process half the info in things i see but haveing you guys to help me get on track is the world i really appreciate you all for your time and what you do when i finish this batch finally im quitting out of the hobby to get back on track mentally bc i started from grieving my uncle and then it was recently a 24 year old pet i was extremely close with)

 

[acpeacemaker]

There's a few ways you could filter. But something like that I always used a charmin plug. Simple to do. It will be slow.

I would definitely incinerate that mess.

 

[Martijn]

I wasn't sure incineration would work on AP 'slime' because of chlorides. I thought burning off chlorides would result in loss of gold.
Filters that let gold foils pass are no good. Which ones do you use?
I use the brown coffee filters for small work and the bigger folded filters for waste treatment and copper cell slimes.

 

[Papi980]

Honestly i have no idea how incineration is done ive youtubed it alittle but it was for ic chips do i just throw borax in the bowl and torch it carefully and i use just coffee filters from wallmart i didnt know what or where to buy

 

[FrugalRefiner]

Now is the time to use the forum's search function instead of youtube. You'll find thousands of posts about incineration. Yes, I understand, it's a pain in your butt to have to read through them all to find your answer. Just understand that it's a pain in the butt for us to answer the same question for the thousandth time.

In this case, incineration is taking the "stuff" you have, heating it in something like a stainless steel frying pan till it's dry, then taking it a little farther till it's a dull red hot.

Dave

 

[acpeacemaker]

I wasn't sure incineration would work on AP 'slime' because of chlorides. I thought burning off chlorides would result in loss of gold.
Filters that let gold foils pass are no good. Which ones do you use?
I use the brown coffee filters for small work and the bigger folded filters for waste treatment and copper cell slimes.
.jpg

In this case I think it would be a minimal loss being there's probably already a loss due from "the already" to just a noob doing it. But being the gold is probably mostly still foil form and not a chloride, I would incinerate. Sometimes you gotta pay the piper to still come out with something...Soap residues is like tin for me. I can't stand it. I ran into it more so often when labware wasn't properly cleaned.

I've used many filters. My favorites for minute particles are charmin or sock vac. Regular plain Jane coffee filters work for a lot of things. I had a conversation with gsp about the oversized commercial Bunn coffee filters. Don't recall what he wanted them for. I got them at Dollar General for like $2 for 100. They fit perfectly in a colander sitting on a five gallon bucket. Perfect for ap stuff.


That cake will compact down and soap residues will stay trapped. While heating you need to break the clumps up. I would still go with a charmin plug but that's just my preference.

Also as Dave mentioned you can use a skillet.... Some use like a small casserole dish. You can get them dirt cheap at flea markets.
My favorites are the small stoneware baking dishes for making little loaves of whatever. They used to be $3 at Walmart. They hold up to everything and the glaze stays super slick. (Helps with powders)

On a side note after incineration. You need to try boiling with water. It will save you a future headache if you still have residues trapped in the mix.
Andrew

 

[1mysurveymail]

The infamous grey mud is most likely Sn (tin). It comes from putting too much garbage in your AP. Also from trying to wash with too much water, which reduces the acidity and lets the TIN come out of solution (grey mud). NEVER RINSE OR ADD WATER BACK INTO YOUR AP! This is the cause of most muddy situations when first getting AP technique under your belt. Another is, "garbage in, garbage out."

All the previous advice from other replies is good.

Keep in mind that these are THREE separate batches. One very clean, the other MOBO pins, and the third HDD connectors with OBVIOUS partial plating from old IDE type.

What I do with my recovery / filtration of foils from AP is the let the filter do the work.


Then when all you see is gold in the filter place over some other container (NOT YOUR AP) wash with water.



Here is the "dirtiest rinse" with copper and tin.


This filter rinse comes from this "dirty" batch of IDE hard drive connector pins that I did in my "DIRTY AP bucket (lots of TIN IN SOLUTION)

The "good AP" rinse is from this batch of motherboard pins and connectors:



I would start with a small sample of you mud, and add HCl. It will dissolve the Tin back into solution. Then filter out your gold. The advice of incinerating is good too. THere is a way to dissolve the tin with NaOh, but I forgot it.

Make some stannous testing solution from some "lead free" solder and HCl. Don't throw anything away. Just label it all carefully. As a hero of mine often says, "The gold is still in there."

Good luck