1st attempt using AP - Comments & Questions Welcomed

[cejohnsonsr]

After quite a bit of study I made my 1st attempt to recover & refine gold using the AP method per lazersteve's videos. Everything went pretty much as expected with a couple of minor exceptions. I'm sure it must have been warmer when Steve made his videos in Fl. I'm in Joplin, Mo & the temp has been as high as 50 & as low as 20. During the initial phase of the process I never got much of a visible reaction in the buckets. I'm fairly certain this is due to the low ambient temperature. Regardless, the result was the same. I got the same color changes at about the same times & shortly before the 36 hours was up, virtually all of the fingers/foils released into the acid solution. What remained on the boards (I visually inspected & rinsed each board individually) &/or on the filter(s) is less than my scale is able to weigh (.01). So far so good.

After thoroughly washing with HCl & rinsing with distilled water I proceeded to dissolve in fresh HCl & chlorine bleach. Again, everything went exactly as per lazersteve's video & the gold was completely dissolved in about 20 min. I filtered the sludge out & what remained was a very golden yellow, clear solution. I believe the proper term is Auric Chloride (AuCl?) So far so good.

After allowing the chlorine to dissipate over night I reviewed lazersteve's "Using SMB" video & here is where I may have misunderstood & possibly made a mistake. He said something about the solution being diluted 3 times. I took that to mean that the AuCl had been diluted so I diluted mine. I had just under 2 cups of solution & my beakers wouldn't hold enough so I divided the AuCl into 2 1000 ml beakers (about 350 ml in each) & added enough distilled water to make each about 700 ml. I don't think I should have done this. Also, Steve used SMB which had been dissolved into a saturated solution. I wasn't sure how much solution or exactly how much SMB to saturate, so I used the SMB in powdered form. These exceptions & the temperature are the only deviations from lazersteve's video. The problem came when I added the SMB. One beaker eventually turned clear, then clouded, then turned a very dark muddy looking color just like in the video. The other one never cleared & no matter how much SMB is added it always turned back to about the same yellow color as when I started. After a while I was certain no more SMB would dissolve because there was a little bit laying in the bottom of the beaker that wouldn't dissolve no matter how much I stirred. After 24 hours the muddy colored beaker has settled out. The solution is clear, though it seems to have a slightly brownish tint to it. This might be due to the ambient light & the flection of the brownish gold that has settled to the bottom. Most of the SMB has dissolved into beaker number 2 & there are a few very small bubbles rising to the top. Otherwise it hasn't changed at all.

I've made a few educated guesses as to what occurred. First, I shouldn't have diluted the original AuCl. I should have used it as it was. Second, when I divided the solution into 2 beakers I didn't stir it. I think while it sat overnight the gold actually settled into the lower half of the container. When I poured the first half off, it didn't have much, if any, gold in it. That would explain the results of the stannous chloride tests which were a bit confusing.

I believe I'm ready to proceed with the process, but I'm not sure what I should do with the beaker that failed to drop. Being saturated with SMB, is it usable for anything? I'm open & appreciative of any constructive criticism as well as suggestions to help improve my skills. As always, I will continue to study and learn as much as possible on my own.

Thank you,

Ed

 

[kkmonte]

Hmm, How many pounds of fingers was this? That seems to me to be alot of AuCL (700 ML total) if it wasn't diluted first? Unless you were doing a ton of foils I would guess. In Steve's video, he has 3 grams of foils, and uses about half a cup of acid. Maybe you just added a lot more acid than was needed? How much Chlorox did you add? If you added too much chlorox, the chlorox will eat the SMB so maybe you just need to add more SMB to the yellow solution.

What does the Stannous test show on the beaker with the yellow liquid? Again, i'm a beginner also, so hopefully people won't say I'm an idiot and don't know what i'm talking about.

 

[butcher]

cejohnsonsr, somethings I might try.
Let it sit over night to settle (if you have not already), decant solution (do not disturb powder), filter the clear solution to a clean vessel, which you can heat, heat the solution, if there is chlorine this will drive it off, you can see if you smell Chlorine or SO2 gas, a test you can try for chlorine pour a little ammonia in a cap from the bottle we do not need much and do not want to spill the ammonia, hold this capful of ammonia in the stream of fumes and vapors from your gold chloride solution, the ammonia will also be releasing gas hence the smell of ammonia from the capful, when these two gases come together if you see a white cloud form it is ammonium chloride gas, ammonia gas and chlorine gas mixing to form a white cloud of ammonium chloride gas, no white cloud, then no chlorine in the gas coming from your solution.

I doubt gold settled in solution it is dissolved, unless maybe ice crystals formed and the frozen water shoved out the dissolved gold chloride salts, other wise it should be fairly well dispersed throughout the solution. I do not think you would have trouble from dilution, as kkmonte, said most likely chlorine in solution.

Also as kkmonte asked, you stannous test can let you know what may be going on besides being an indicator if gold is in solution, it can also be an indicator if the gold will reduce or not, example say I have a little too much oxidizer, chlorine in this case, and I do the stannous test, it turns violet and then the violet color disappears again, my gold at first reduced by the stannous and then re-dissolved in the chlorine, a test in a spot plate (or white plastic spoon) can show this up sometimes a little better than on a paper, so here if the stannous test stays violet we have a better chance of being able to reduce our gold back to metal.

 

[cejohnsonsr]

In Steve's video he started out with 600 gr of fingers & ended up with 3.1 gr of gold. I started with a little over 144 gr of fingers. My mixtures were the same ratios as Steve's only in smaller quantities. I would up with so much fluid at the end because I diluted with distilled water. I'm certain that was a mistake. I added SMB to the yellow beaker until it was so saturated that no more would dissolve. When I added the bleach I did it the way Steve did. I just put in a little until it fizzed. Then I did it again. All of the foils dissolved. My problem was that I divided the AuCl into 2 beakers so I could dilute it. Again, I'm sure that was a mistake. What I think happened is that while sitting for about 12 hours to dissipate the bleach, all the gold settled to the bottom of the AuCl. So when I poured the 1st (top) half off, there was really no gold in it. The stannous test showed a yellowish to VERY light brown color for that beaker. The other beaker (from the bottom half) reacted to the stannous & SMB as expected. I let it settle for 24 hours & then washed & rinsed per Harold's instructions (more or less). It's 0234 Central Time & I just put the results on a low heat to dry. It's a light brown powder, just about like what Steve had in the video. MUCH lighter after washing & rinsing. I'm only guessing, but I think I have pretty close to 1 gr, which would be in line with Steve's yield. Anyone who didn't know better would think it's a pitiful little puddle of mud after all the work I put into it, but I wasn't going for quantity on my 1st attempt. My goal was to make sure I understood what I thought I understood. I think I have accomplished that so far. Like Steve says, the proof is in the pudding.

As far as being a newbie, me too. We're all in this together. I'm very thankful that so many people are willing to share their knowledge & experience with guys like you & me. The trick here seems to be to do your own work 1st. Put in enough genuine effort to try to learn from what is already available here. Then, when you either can't find something, or don't really understand what you found, asking the right question(s) as clearly, precisely & articulately as possible makes all the difference. These guys don't suffer fools or the lazy. If you can do that, you can expect what help you need when you need it. I'm looking forward (hoping) to hearing what the more experienced among us have to say.

The light isn't very good. I hope you can see my pitiful little puddle of mud. That's a 100 ml beaker.

Ed

 

[cejohnsonsr]

Thank you, butcher. I'll give that a try tomorrow after I'm well rested. This has been a long day. I hope you're right & I can get another little puddle of mud! I posted just after you did, so some of the answers to your questions are in that reply. More tomorrow. Good night all!

Ed

 

[kkmonte]

Hmm well let us know how you make out. My first batch was 151 grams just to see if i got the procedure down and I only ended up with about .5 grams of gold powder after drying, and cleaning, etc. I guess it all depends on how good the ~1/3 of the pound of fingers were.

 

[Pantherlikher]

Ok...
I'm no pro but have great common sense so bare with.
You've followed everything and sounds like descent results but with doubt.

Store all liquid and let it evaporate. Heat if you can.
Removing H2O and reducing your over dillution you question.
Or... impatient, like myself, Stick steel in it and give it a few days to drop everything. That will definitively tell you if you've gotten all the gold.

For the learning experience, see what's left and review what happened and work on why...
Excelent you've done your school work and have something to show for it.
Now finish and review.
Nuff said right?

BS.
Self doubt without proving accomplishes nothing...

 

[cejohnsonsr]

Thanks for the help, advice & encouragement guys.

Pantherlikher, I think I'm going to try your suggestion(s), but I may have made another mistake. I saved the liquid from the nonreactive beaker but I dumped the sediment (SMB from over-saturation) in with some other waste. Now I'm not quite sure how to proceed, but I really would like to try to correct any mistakes I made & learn more from it if I can.

For the record, my pitiful little puddle of mud turned out to be .26 gr after washing, rinsing & drying. It may actually be a little less after it's processed a 2nd time in AR, but I doubt we'll ever know for sure. I can't see processing that little bit alone so I'm thinking it will go in with a larger batch of ceramic CPUs. Whatever it is, it's bound to be better after a 2nd run. Right?

I'm also about to start another AP batch with some circuit board scrap. I have to remove solder mask 1st. I'm going to use lazersteve's sodium hydroxide method for that as well. This time, when I get to that point, I WILL NOT DIVIDE & DILUTE. (Actually I may not get to that point this time. See the thread "Knowing which process to use...." in this forum for details.)

Ed

 

[butcher]

Dilution of gold chloride may change things a little bit, but basically it would not keep you from precipitating your gold from solution.

You can precipitate gold from concentrated or dilute solutions (within reasonable limits), there can be some differences in how they may react, or what state the gold precipitated, but dilution would not keep you from precipitating the gold.

Dilution would effect oxidizer (chlorine) in solution and how easily it stayed in solution, especially if solutions were cold, the chlorine would be more dispersed and will stay in the cold solution, but if solution was boiled the chlorine would quickly be forced out of the solution no matter how dilute it was, if you have gold in this solution it would be simple to get it back, even if you mixed these two solutions back together, actually one of your solutions had too much SMB, the other if it did not have too much SMB but had excess chlorine in solution keeping the gold dissolved, you could put both solution in one vessel and heat it, the gold may just begin to precipitate, if not then using your stannous, you nose to see if you smell chlorine or SO2 gas, and the ammonia test to determine what you need to do to get the gold to precipitate, if all else fails you can cement the gold out of solution with your copper buss bar as black powder of impure gold (black powder you could add to your next recovery project).

I would not put the gold you just recovered with the next batch of CPU's or any other material you are trying to recover again, it would do no good to this gold, would just use more reagent, it would not improve this gold at all, and could just contaminate it, also if your next recovery project had problems you could just lock this gold up in that mess, save this gold, go ahead and recover more gold from your other materials, then you can add it to this gold saving it up until you have collected enough, then wash the gold and do the second refining.

 

[cejohnsonsr]

Well guys, I'm learning quite a bit tonight. I hope I can keep up.

kkmonte, I started with 144.03 gr & got .26 gr. Since I'm pretty sure something was wrong with half of my AuCl I figure I only got half the yield. that would put us in pretty much the same ball park. Like you, I was trying to make sure I had the process down pat. It was a test to see if I could do it more than anything & to learn (hopefully) from my mistakes.

butcher, it really was cold when I did this. Down around 20 the night I let it set to dissipate the chlorine. I kinda think I didn't let it sit long enough anyway. Also, I didn't use any heat at all during the entire process until I started washing per Harold's instructions. The 1 beaker was over-saturated with SMB & produced no reaction (gold) at all. The other beaker dropped .26 gr after washing, rinsing & drying. Stannous showed no color at all on this beaker but the liquid has a slight color to it. Just kinda not completely clear from the muddy color it had when the SMB began to work. I think I'll combine the 2 again & heat it up a bit to see what happens. If that doesn't work I'll try the copper. The term "cement" is something I've seen used a few times in my study but I admit I don't really know what it means. It's on my list of things I need to understand (with about 4 or 5 added daily!). And I promise not to mix scrap of different types. I've been getting a real education on that subject too from my other current thread.

Thanks again. I'll keep checking back for any more input, which is always appreciated, & to update my results.

Ed

 

[steyr223]

Just curios but are you filtering your
Aucl
after you dissolve your gold,
but
Before you add smb

If so how? , the preferred method is
Harolds Charmin plug but i believe many
Now use fiberglass in place of tissue paper.
Steyr233 rob

 

[jeneje]

If that doesn't work I'll try the copper. The term "cement" is something I've seen used a few times in my study but I admit I don't really know what it means.

When you cement solution using copper or iron - you are transfering a metal higher in the reaction list into the solution causing the lower metals below it to drop out as a fine powder that is the way i understand it. This may not be the correct terminology. If not someone will correct me.
Ken

 

[cejohnsonsr]

Steyr223 (Rob), I followed lazersteve's video through the whole process. I filtered the solution through 4 coffee filters before dividing, diluting & adding SMB. I'm posting a pic below so you can see the filters after filtering. As you can see, I should have been a little more patient. This is after only about 15 or 20 minutes. I should have stirred at least 2 more times & waited another 20 minutes. It was very cold the night I dissolved.

jeneje, thanks for the explanation. I'm going to start reading Hoke today. I've been putting it off for too long. I'd bet $ I'll get a pretty good explanation when I get to that part.

Ed

 

[steyr223]

Ed hello
The picture ? Are these yout gold powders after precipitation.
I dont believe steve shows any filtering of yout auric chloride
(actually dumping your golden solution into a funnel
With a piece of fiberglass in the small end of
The funnel)
This will take an ugly brown or green cloudy solution
and turn it Into the most crystal clear golden to orange you have ever
Seen.
Steyr233 rob

 

[cejohnsonsr]

Rob, on Steve's video (the 4 part "Processing fingers in AP") he filters through coffee filters & a plastic colander. It works pretty good. I got the same results he did to that point. A nice clear, golden yellow AuCl solution. The pic shows the filter with the sludge & a little bit of undissolved gold. I should have been more patient.

Butcher, I did as you suggested. I put about 400 ml of the nonreactive solution in a clean beaker & heated it up until I had about as vigorous a reaction as I'm comfortable with. I let it bubble for about 35 minutes at which point the bubbling had slowed to almost nothing. By that time the solution was as muddy as could be. Just like when Steve poured the SMB into his AuCl in the video. In fact, I think this looks better than the other beaker that yielded .26 gr. I'm going to let it settle for 24 hours & see what I get. I kept all of the original solution from both beakers. I'll probably run it all just to see what happens. I know I used way more SMB than I should have needed on both. (Note to self: Next time use some heat to drive out excess chlorine before dropping with SMB.) Thanks for the help! I was a little disappointed when this half didn't produce anything. (More than a little confused too.) I'm a pretty happy camper right now. I know it's not much gold, but being able to figure out what went wrong & correct it is important to me. I can't (won't) move on until I'm sure I have this whipped. If I did, I'm pretty sure I'd just have the same problem on a larger scale. I really appreciate it. I'll keep you posted.

Ed

 

[cejohnsonsr]

Good news to report. After settling for 24 hours the solution has cleared & there is a fine brown powder (mud) in the bottom of the beaker. I've only run about half of the nonreactive solution, but there appears to be at least as much mud in the bottom of this beaker as there was in the original "good" beaker. I only eyeballed it for a minute. It's very cold & a winter storm coming today. I won't really know how much more dropped until I can get it washed & rinsed & dried. If I can get my basement/"lab" warmed up enough I might try that tonight.

Ed

 

[cejohnsonsr]

It's true what they say about learning more from your mistakes than from your successes. I heated the rest of my AuCl from the original nonreactive beaker today. We had a winter storm last night & it's much colder than when I ran the 1st half the other day. I had to apply more heat to get the reaction going & it took longer, but I got it done. I also noticed that after setting for a couple more days the original good beaker had more powder in the bottom. I have decanted all of the solution through a charmin plug (except for what I heated today) & collected as much of the powder as I could. I'm pretty sure I'll have way more than double my original .26 gr after all is said & done.

I guess the only issue I'm left with is the "used", filtered solution. I'm pretty sure all of the peroxide was used up during the 1st phase of the AP process. I'm certain all or most of the bleach was driven out when I heated it up. The only other thing in it was water which I think was probably mostly evaporated during the heating. So am I correct in thinking that what's left is just about pure HCl? It's very clear & has the same pungent odor as when I 1st poured it into the bucket. If so, I'm thinking I can reuse it in the next AP batch. Would you guys use it as is, or would you freshen it up a bit? If you'd freshen it, how much fresh HCl would you add to a given amount of the "used" HCl?

Thanks again to everyone who helped me get this worked out. I'll be checking in to see if anyone has anything to add. Hopefully I'll get confirmation about the HCl. Once I've finished recovering the last of the powder & washed, rinsed & dried, I'll post the updated yield. Then I guess that'll be about it for this thread.

Ed

 

[steyr223]

Ed how are you doing today
I believe you're still a bit confused ,at least I am
You said all the proxide is used up ,of course it
was ,that's why your using the bubbler to turn the
HCL with added copper ( from your boards) into
Cu(2)Cl.

The hydrogen peroxide was just to kick start the
Reaction to get HCl to eat a little copper.
Now that you supply air the the reaction
Continues.
Now you say the bleach was evaporated
But you put bleach in your AuCl to
Dissolve gold not in your a/p
And normally you dont heat a/p
If your asking about your used now
Barren AuCl(this would be called somrthin
Entirely different now) you would pour
It into a stockpot marked exactely what
It is and study up on why you dont
Feed it to the fishys in the ocean :lol:
Do not pour it back in the a/p
Steyr223 rob
Ps to freshen the a/p after 4 or 5 big
Batches you add just a little hcl around
30ml ,others can tell you by the color what
To do:

 

[butcher]

The HCl when used to dissolve metals is no longer HCl, but a salt of that metal and the acid that formed it, these salts can have some free HCl or they also can just be naturally acidic salts, or even neutral salts, losing the hydrogen in the process depending on the metal involved.

Hydrochloric acid plus copper (oxidized copper of course), make a salt of copper, copper chloride dissolved in water.

If we forget about the metals involved for just a moment and just look at mixed HCl and bleach NaClO we get a solution of water (H2O) and sodium chloride (NaCl) (table salt), and volatile chlorine gas (Cl2) leaving the reaction, as well as a few other minor products, if we had a metal to the solution we would also have metal chlorides, salts of those metals involved.

2HCl + NaClO --> NaCl + CL2(gas) + H2O
Then
When chlorine leaves the salt water, we have, you guessed it, saltwater.
NaCl + H2O
If metals were involved these salt waters could contain metal chlorides (salts of those metals involved), some metals salts as you know are very toxic.

 

[cejohnsonsr]

For steyr223:

You said all the proxide is used up ,of course it
was ,that's why your using the bubbler to turn the
HCL with added copper ( from your boards) into
Cu(2)Cl.

I'm not using any copper or a bubbler. I followed along with lazersteve's 4 part video, "Removing fingers with AP".

Now you say the bleach was evaporated
But you put bleach in your AuCl to
Dissolve gold not in your a/p
And normally you dont heat a/p

Again, following lazersteve's videos, the AP & AuCl are separate solutions used at different stages of the process. AP to strip the fingers & AuCl to dissolve.

dont Feed it to the fishys in the ocean :lol:
Do not pour it back in the a/p

I have my used solutions marked & stored properly with the hope that I can re-use some or all of it. THERE IS ABSOLUTELY NO CHANCE THAT I MIGHT DUMP ANY OF THIS STUFF DOWN THE DRAIN.

Thank you, butcher. I'm going to have to study what you wrote at least 2 or 3 times over & I probably still won't really understand it. In my 1st attempt at college, after 3 semesters as a bio/chem double major, the only thing I REALLY learned is that chemistry is as hard as woodpecker lips & I will never be a chemist. I'm not stupid or anything. Computer science didn't give me any problem at all. I finished my degree near the top of my class. But something about the mathematics of chemistry just didn't click for me. I really wish I could get the hang of it. I'm trying. In the mean time, I'm a really good lab tech. With good instructions I can follow/perform very complex procedures successfully. And when things go wrong, as this 1st attempt did, I can recover if I just get a little help. You gave me that help. Thank you very much. Now, having said all that........

After washing rinsing & drying I increased my yield by .17 gr from .26 gr to .43 gr. I think .5 gr would have been more in line with what others have gotten from similar samples (144.03 gr), but I'm happy. My goal was to learn to perform the procedure properly & actually recover the gold. Also, I should mention that there could very well be .07 gr in the filter papers & charmin plugs, but that's not enough to justify what it would take to recover it. And, finally, to be perfectly honest, I may have just a little less than I think. The powder I recovered from the 2nd half, though less in quantity, is of much higher quality. I was learning & getting better as I went. The washing, rinsing & drying of the 2nd half was more thorough. The result was a better product.

Thanks to everyone who helped me through this. Special thanks to lazersteve for the excellent videos (many of which are free) that I used as a guide to this process. And also to butcher who helped me to understand what went wrong & recover from it.

Ed