Solid fully plated pins
229g twice refined = 0.599g
229g twice refined = 0.599g
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For Sale ~15lbs of gold plated pins.
- Thread starter jdgodz1984
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Nice
More styles to come, there are lots of different ones!
I've actually been trying all kinds of recovery, trying to find the most suitable.
The solid pins, I disolved base metals with nitric, the disolved foils in AR. That was very time consuming and used a lot of nitric for a small return.
The pogo barrels went into copper(2)chloride leach and took a month but was relatively hands free and then foils to AR.
I want to try straight AR digestion now and make a dirty drop which I'd then refine. Seems like that might be faster and use less nitric. Someone actually recently told me that you may be the guy to talk to about such a process. Have you tried this method?
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I found the CuCl2/HCl leach the most comfortable, if applicable and if you have time to leave it sitting until finished.
The biggest drawback to me: When you regenerate the solution with HCl and an air bubbler, it is very corrosive to every metal in the area. Small amounts of HCl evaporate by the exchange of gasses from the bucket and will quickly rust everything. The regenerated solution in a closed bucket is no problem. Regenerating with H-perox also does not have this problem. But it is a costly reagent, compared to free air.
I have the regenerator bucket outside behind the shed. As I am planning to build/buy an oxygen concentrator soon, I think pure oxygen will probably speed it up to leave it running in the fume hood.
The biggest drawback to me: When you regenerate the solution with HCl and an air bubbler, it is very corrosive to every metal in the area. Small amounts of HCl evaporate by the exchange of gasses from the bucket and will quickly rust everything. The regenerated solution in a closed bucket is no problem. Regenerating with H-perox also does not have this problem. But it is a costly reagent, compared to free air.
I have the regenerator bucket outside behind the shed. As I am planning to build/buy an oxygen concentrator soon, I think pure oxygen will probably speed it up to leave it running in the fume hood.
I really do like dissolving base metals with nitric and then finishing with AR it just uses so darn much nitric. I like the CuCl2 leach but absolutely hate vaccuum filtering the massive amount of nasty black solution. I guess it's all a "give and take". I have a LOT of different styles of pins to work through!
Allow your CuCl2 to fully settle, then decant the clear solution from the majority, temove the upper most volume, this way you filter a smaller volume of the solution. I once filtered two five gallon buckets of AP and hope to never do it again.
Yeah
kinda... Practically, I never used anything else for production processing for over 8 years. If you are up for speed + use the least amount of nitric, straight AR is your choice.
+ no issues with metastannic acid or eventual stainless/ferrous materials/aluminium during processing - this is huge thing if you will scale up sometime and want to save time by doing bigger mixed batches of all kinds of scrap.
4L HCl + 1-1,2L nitric for kilo of copper based scrap. For ferrous based less nitric and more HCl. Adjust from case to case, this is only empirical ballpark number. Never fill the beaker more than 40 % of volume (if you are novice to AR). Try to never go past 80 °C as you will unnecessarily evaporate HCl and waste active nitric. Dump in all of the HCl and material, preheat to 45-50 °C and add 1/4 of nitric. Wait for it to start rolling, and watch for foam level. When foam goes down and start to break into patches, quickly start adding nitric in small quantity to sustain the reaction. NEVER let the AR dissolution die down from rolling reaction - as it will tend to erupt gasses upon addition of fresh nitric. Nearly everything regarding AR is delayed and have some sort of induction period - be aware of this and it will serve you well
No silver in material, the least amount of junk (plastic, PVC sleeves from cables, whole connectors etc.) - and you should be good to go.
AR outgas is very corrosive, worse than NOx outgas. Anything metallic in proximity of your operation will rust, if you will scale this up into kilogram range on regular basis.
Dirty drop is not necessarily that "dirty", and I regularly got above 995 with "dirty" drops. My material averaged in range of 4-15g/kg. For less than 2g/kg it stopped to be an interesting process for recovery, as amount of waste per gain generated was quite low. But same apply to nitric or AP leach.
Do not de-NOx and drop with SMB, do the "dirty" drop with paired action of sulfamic acid + copper. Add sulfamic in a way fumes escaping the beaker will be colourless. If not, add more sulfamic. And importantly, do this HOT, gradually bring the pot just under the boiling point - traces of nitric will properly react and die, all of the gold will drop (very visual and very nice to watch), it will coalesce after some time simmering. When solution get very deep, dirty green-brown/brown (sign of simultaneous presence of Cu(II) and Cu(I) ), stir it from time to time over the course of 20-30 minutes to assure effective contact with copper plate/bar (solution will go from green, to cloudy green, cloudy green-brown with visible deposit and finally nearly "clear" deep brown). Now, all of the gold is out of solution - no need for stannous test (but we will do it anyway... at least my paranoid self
). Stop the boiling, cover the beaker with something to minimize air exposure and force-cool the beaker in bucket of cold water until it´s like 45-50 °C. Take out copper and let it settle. Decant or filter, it is up to you. Wash with cold concentrated HCl until colourless filtrate/decant is obtained. Then water until neutral pH and dry.250g sample in 5L beaker can be done in 5 hours to the dry gold powder. Not joking or exaggerating.
Exactly what I'm looking for, THANK YOU orvi!Yeah
If you are up for speed + use the least amount of nitric, straight AR is your choice.
+ no issues with metastannic acid or eventual stainless/ferrous materials/aluminium during processing - this is huge thing if you will scale up sometime and want to save time by doing bigger mixed batches of all kinds of scrap.
4L HCl + 1-1,2L nitric for kilo of copper based scrap. For ferrous based less nitric and more HCl. Adjust from case to case, this is only empirical ballpark number. Never fill the beaker more than 40 % of volume (if you are novice to AR). Try to never go past 80 °C as you will unnecessarily evaporate HCl and waste active nitric. Dump in all of the HCl and material, preheat to 45-50 °C and add 1/4 of nitric. Wait for it to start rolling, and watch for foam level. When foam goes down and start to break into patches, quickly start adding nitric in small quantity to sustain the reaction. NEVER let the AR dissolution die down from rolling reaction - as it will tend to erupt gasses upon addition of fresh nitric. Nearly everything regarding AR is delayed and have some sort of induction period - be aware of this and it will serve you well
No silver in material, the least amount of junk (plastic, PVC sleeves from cables, whole connectors etc.) - and you should be good to go.
AR outgas is very corrosive, worse than NOx outgas. Anything metallic in proximity of your operation will rust, if you will scale this up into kilogram range on regular basis.
Dirty drop is not necessarily that "dirty", and I regularly got above 995 with "dirty" drops. My material averaged in range of 4-15g/kg. For less than 2g/kg it stopped to be an interesting process for recovery, as amount of waste per gain generated was quite low. But same apply to nitric or AP leach.
Do not de-NOx and drop with SMB, do the "dirty" drop with paired action of sulfamic acid + copper. Add sulfamic in a way fumes escaping the beaker will be colourless. If not, add more sulfamic. And importantly, do this HOT, gradually bring the pot just under the boiling point - traces of nitric will properly react and die, all of the gold will drop (very visual and very nice to watch), it will coalesce after some time simmering. When solution get very deep, dirty green-brown/brown (sign of simultaneous presence of Cu(II) and Cu(I) ), stir it from time to time over the course of 20-30 minutes to assure effective contact with copper plate/bar (solution will go from green, to cloudy green, cloudy green-brown with visible deposit and finally nearly "clear" deep brown). Now, all of the gold is out of solution - no need for stannous test (but we will do it anyway... at least my paranoid self
250g sample in 5L beaker can be done in 5 hours to the dry gold powder. Not joking or exaggerating.
Orvi, I tried this procedure today and it worked flawlessly! 1L HCL and about 260ml Nitric disolved 250g of heavily plated pins. My biggest beaker is only 2L so I had to use what I had on hand but you're absolutely correct, as long as a rolling reaction is kept going with small additions of nitric it all stays in the beaker. You really have to stay on top of that, I turned my back for 5 min after the first quarter lot of nitric and lost it and it was a bit tedious to get rolling again. The one difference was the color change, they went as you described until the end, it never went "clear" brown but a very deep brown pretty much like saturated CuCl2 leach. I haven't decanted yet to retrieve the precipitated gold yet but it's beautiful yellow colored, way more clean looking than when I drop with copperas or smb.Yeah
If you are up for speed + use the least amount of nitric, straight AR is your choice.
+ no issues with metastannic acid or eventual stainless/ferrous materials/aluminium during processing - this is huge thing if you will scale up sometime and want to save time by doing bigger mixed batches of all kinds of scrap.
4L HCl + 1-1,2L nitric for kilo of copper based scrap. For ferrous based less nitric and more HCl. Adjust from case to case, this is only empirical ballpark number. Never fill the beaker more than 40 % of volume (if you are novice to AR). Try to never go past 80 °C as you will unnecessarily evaporate HCl and waste active nitric. Dump in all of the HCl and material, preheat to 45-50 °C and add 1/4 of nitric. Wait for it to start rolling, and watch for foam level. When foam goes down and start to break into patches, quickly start adding nitric in small quantity to sustain the reaction. NEVER let the AR dissolution die down from rolling reaction - as it will tend to erupt gasses upon addition of fresh nitric. Nearly everything regarding AR is delayed and have some sort of induction period - be aware of this and it will serve you well
No silver in material, the least amount of junk (plastic, PVC sleeves from cables, whole connectors etc.) - and you should be good to go.
AR outgas is very corrosive, worse than NOx outgas. Anything metallic in proximity of your operation will rust, if you will scale this up into kilogram range on regular basis.
Dirty drop is not necessarily that "dirty", and I regularly got above 995 with "dirty" drops. My material averaged in range of 4-15g/kg. For less than 2g/kg it stopped to be an interesting process for recovery, as amount of waste per gain generated was quite low. But same apply to nitric or AP leach.
Do not de-NOx and drop with SMB, do the "dirty" drop with paired action of sulfamic acid + copper. Add sulfamic in a way fumes escaping the beaker will be colourless. If not, add more sulfamic. And importantly, do this HOT, gradually bring the pot just under the boiling point - traces of nitric will properly react and die, all of the gold will drop (very visual and very nice to watch), it will coalesce after some time simmering. When solution get very deep, dirty green-brown/brown (sign of simultaneous presence of Cu(II) and Cu(I) ), stir it from time to time over the course of 20-30 minutes to assure effective contact with copper plate/bar (solution will go from green, to cloudy green, cloudy green-brown with visible deposit and finally nearly "clear" deep brown). Now, all of the gold is out of solution - no need for stannous test (but we will do it anyway... at least my paranoid self
250g sample in 5L beaker can be done in 5 hours to the dry gold powder. Not joking or exaggerating.
BRAVO my man! That was an excellent write-up you gave on your procedure and I accomplished in 4 hours what took me a week to do last time and with WAY less chemicals!
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I am happy to hear that it worked as it shouldOrvi, I tried this procedure today and it worked flawlessly! 1L HCL and about 260ml Nitric disolved 250g of heavily plated pins. My biggest beaker is only 2L so I had to use what I had on hand but you're absolutely correct, as long as a rolling reaction is kept going with small additions of nitric it all stays in the beaker. You really have to stay on top of that, I turned my back for 5 min after the first quarter lot of nitric and lost it and it was a bit tedious to get rolling again. The one difference was the color change, they went as you described until the end, it never went "clear" brown but a very deep brown pretty much like saturated CuCl2 leach. I haven't decanted yet to retrieve the precipitated gold yet but it's beautiful yellow colored, way more clean looking than when I drop with copperas or smb.
BRAVO my man! That was an excellent write-up you gave on your procedure and I accomplished in 4 hours what took me a week to do last time and with WAY less chemicals!
Maybe I mistaken what I wanted to say with brown colour.. It is usually so brown that you cannot see through it even when you pour the barren liquid from the gold precipitate. You can help yourself with LED torch and aim the light beam from under the spout of the beaker to see if any particles are escaping or not.
Gold precipitate is usually very heavy and compact, but do not expect 999 purity from this recovery operation. I make 995-997 on average, and yes, if you have some dissolved silver (as silver chloride in this solution), it will also drop alongside gold.
I use this as a quick and reliable recovery method. Main drawback is that you add additional copper into your waste stream - it is evident and clear. But the amount can be significantly lowered when you pair precipitation/de-NOx with sulfamic acid. NOx gasses generated in solution are further reduced to unreactive nitrogen species, and effervesce from reaction mixture.
Then, if desired, you re-refine the gold obtained, which is an easy task since you will get reasonably pure gold precipitate.
In "production mode" I didn´t even filter the solution from dissolution in AR - I just strained it through tight mesh strainer to get rid of obvious floating debris, and then immediately dropped with copper/sulfamic. This is much easier then setting up for regular filtration, no need to cool down the juice - you save time and energy. Not suitable for every instance, but like 90% of a time, you will be OK with this.
This is definitely my favorite recovery method!I am happy to hear that it worked as it should
Maybe I mistaken what I wanted to say with brown colour.. It is usually so brown that you cannot see through it even when you pour the barren liquid from the gold precipitate. You can help yourself with LED torch and aim the light beam from under the spout of the beaker to see if any particles are escaping or not.
Gold precipitate is usually very heavy and compact, but do not expect 999 purity from this recovery operation. I make 995-997 on average, and yes, if you have some dissolved silver (as silver chloride in this solution), it will also drop alongside gold.
I use this as a quick and reliable recovery method. Main drawback is that you add additional copper into your waste stream - it is evident and clear. But the amount can be significantly lowered when you pair precipitation/de-NOx with sulfamic acid. NOx gasses generated in solution are further reduced to unreactive nitrogen species, and effervesce from reaction mixture.
Then, if desired, you re-refine the gold obtained, which is an easy task since you will get reasonably pure gold precipitate.
In "production mode" I didn´t even filter the solution from dissolution in AR - I just strained it through tight mesh strainer to get rid of obvious floating debris, and then immediately dropped with copper/sulfamic. This is much easier then setting up for regular filtration, no need to cool down the juice - you save time and energy. Not suitable for every instance, but like 90% of a time, you will be OK with this.
Yeild from 500g of this style pins. Recovery was Orvi's AR dissolution method (only I'm out of nitric acid so i used PMAR with potassium nitrate) cemented out on copper with addition of sulfamic acid, decanted, washed, redisolved in PMAR, cold filtered twice through same Watman #1, dropped with copperas, washed, dried and then melted. I'm getting better at this, it's by far my best looking gold powder so far and a real nice looking button 
