# Iodine leach



## patnor1011 (May 10, 2020)

Look and marvel how fast it is 
While it is one of the more expensive methods it may be a solution for people who do not have access to cyanide or do not want to work with hot sulfuric, wait a long time for AP or create a lot of waste dissolving plated material. 

[youtube]https://www.youtube.com/watch?v=p39UdRKFZRs[/youtube]


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## rickzeien (May 10, 2020)

Really nice demonstration. So it does not effect the copper, stainless steel or nichol substrate? Or if it was left to long it would put those in solution as well?

I asked some questions on your leach system video post? I would have asked here if I saw this first. 

Should I move those questions to here?

Thanks for sharing?



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## kurtak (May 10, 2020)

Very cool Pat 8) 

couple questions - what is the percent/strength of the iodine - where do you get it & are there restriction on how much you can get over there

I ask because over here in the U.S. they made iodine a "list 1" restricted/regulated chemical due to it being a chemical used for making meth so here in the U.S. you can only get it at 2.2 % & are limited to the amount you are allowed to buy - in other words very restricted here unless you jump through a bunch of hoops to be certified 

https://www.federalregister.gov/documents/2007/07/02/E7-12736/changes-in-the-regulation-of-iodine-crystals-and-chemical-mixtures-containing-over-22-percent-iodine

Kurt


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## butcher (May 10, 2020)

It has been years since I bought iodine, I had no trouble purchasing it at the feed store (iodine for Thrush treatment of horses hooves), I just had to show several forms of identification, and fill out some federal forms.

https://www.google.com/search?q=thrush+iodine&sxsrf=ALeKk020WkuR0R36YJqr6de7Knnvxw4yVQ:1589123160717&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjzuf6LyanpAhWJvZ4KHdiICw4Q_AUoAnoECA0QBA&biw=1024&bih=705


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## patnor1011 (May 11, 2020)

rickzeien said:


> Really nice demonstration. So it does not effect the copper, stainless steel or nichol substrate? Or if it was left to long it would put those in solution as well?
> 
> I asked some questions on your leach system video post? I would have asked here if I saw this first.
> 
> ...



Rick, it does not affect stainless - I did not observe that but it will dissolve copper if left there too long. At least that is what I saw when I put in some broken pinless cpu with some layers of copper exposed. I saw white milky stuff coming off which can be copper iodide - but that is just my guess. 
My son is starting to study chemistry at university so he will be like my tutor in things theoretical in a short time 
Leach solution was prepared from distilled water, potassium iodide and iodine crystals in ratio 10:4:1


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## patnor1011 (May 11, 2020)

kurtak said:


> Very cool Pat 8)
> 
> couple questions - what is the percent/strength of the iodine - where do you get it & are there restriction on how much you can get over there
> 
> ...



Kurt my friend, Iodine is pure crystals. I got it from ebay - 
https://www.ebay.co.uk/itm/250g-Iodine-Crystals-Resublimed-99-9-pure-quality-product/152297085475
There is no restriction to buy this item other than you have to be over 18.
If you cant buy iodine you can actually make it from iodide. Is there any restriction to buy potassium iodide in the USA?


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## rickzeien (May 11, 2020)

patnor1011 said:


> rickzeien said:
> 
> 
> > Really nice demonstration. So it does not effect the copper, stainless steel or nichol substrate? Or if it was left to long it would put those in solution as well?
> ...


Thanks. I am very interested in this leaching method. I have almost everything set up for my own trials. 

I had read that the leach time was very fast now I see in your video that it is. 

Keep up the great work!

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## kurtak (May 11, 2020)

Hi Pat 

Just did a search on potassium iodide (is potassium iodide a restricted chemical) & from what I can see the KI is not restricted like iodine is so should be able to get the KI - have not searched (yet) for where to get the KI

In you reply to Rick you said the leach solution is made with D-water KI (potassium iodide) & iodine at a ratio of 10 - 4 - 1

so that's a 40% KI 10% iodine solution 

As I said - here in the U.S. the iodine is VERY restricted

So - will the KI by its self work - or do you need the KI in combination with the iodine for it to work

Next question - how due you get your gold back after it has gone into solution

Edit to add; - the KI can be found bought on amazon :arrow: https://www.amazon.com/Potassium-Iodide-Purity-Crystals-Granules/dp/B008D8161I#detail-bullets

Kurt


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## rickzeien (May 11, 2020)

kurtak said:


> Hi Pat
> 
> Just did a search on potassium iodide (is potassium iodide a restricted chemical) & from what I can see the KI is not restricted like iodine is so should be able to get the KI - have not searched (yet) for where to get the KI
> 
> ...


I got my iodine/iodide from ebay. 

Have not worked out the ratio or concentration yet so I am not advocating this for use yet. Just want to conduct some trials. 

https://www.ebay.com/itm/250-Grams-99-8-Elemental-Iodin-Crystals-Granule-For-Lab-Chemicals-Kit-TOP/333281725593?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

https://www.ebay.com/itm/Potassium-Iodide-Crystal-Powder-High-Purity-USP-Grade-100gm-250gm-500gm-1Kg-/401772742335

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## patnor1011 (May 11, 2020)

Kurt. I saw some sellers on eBay com selling iodine crystals in the USA. I will look up auction number later on. 
If you can not get iodine there is a workaround. You can get iodine from iodide. All you need is hydrochloric acid and 3% hydrogen peroxide solution.
Dissolve potassium iodide in distilled water add HCl and add peroxide. Then evaporate solution and you will have iodine crystals on the bottom. 
If you Google topic there are a lot of tutorials and videos on the subject. 
Dropping gold with ascorbic. Then rejuvenate solution with peroxide added in drops. 
Check our member owltech videos he did quite a few of them concerning iodine-iodide process.


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## patnor1011 (May 11, 2020)

Rick. I used in my video 300 ml od distilled water 25g of iodine crystals and 100g of potassium iodide.


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## Shark (May 11, 2020)

Very interesting. 

Any idea of how much gold a given volume can hold? Are there signs to watch for that indicate the solution is reaching its load point?


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## patnor1011 (May 22, 2020)

Gold dropped. Beaker is main leach solution bottle is gold off wash water. 
Leach will be rejuvenated and reused again.


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## kurtak (May 22, 2020)

VERY cool Pat :mrgreen: 

Going to have to look into this some more

And thanks for answering my earlier questions 

Kurt


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## rickzeien (May 22, 2020)

patnor1011 said:


> Gold dropped. Beaker is main leach solution bottle is gold off wash water.
> Leach will be rejuvenated and reused again.


Really awesome. What did you use to precipitate with. 

To rejuvenate is it just add more iodide? And at what ratio?

Thsnks for sharing. 

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## otb (May 23, 2020)

Hi Pat, congratulations!
Can you tell us what have you used for dropping the gold?
Thank you!


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## FrugalRefiner (May 23, 2020)

otb said:


> Hi Pat, congratulations!
> Can you tell us what have you used for dropping the gold?
> Thank you!



He mentioned it earlier in the thread.


patnor1011 said:


> Dropping gold with ascorbic. Then rejuvenate solution with peroxide added in drops.



Dave


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## rickzeien (May 23, 2020)

FrugalRefiner said:


> otb said:
> 
> 
> > Hi Pat, congratulations!
> ...


Thanks Dave!

I really should have reread the entire thread. 


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## otb (May 23, 2020)

Thank you, Dave!
Well, I did read it all and a few others in this regards (Iodine) and I think that this thread here is the only achievable for me...
I did see the vitamin C, which is a divine answer to my prayers, however, I would kindly ask for some details about the procedure (cold or warm solution, how much / stop when x happens, etc.)
If someone else is able to share, will gladly share some beers as between friends.
Thank you very much in advance!


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## patnor1011 (May 24, 2020)

It would be expensive to go for beer to Romania I may have to postpone it till retirement and when personal jetpacks will be available :mrgreen: 

As you can see on my videos there was no heating involved other than there was about 18 degree celsius outside. Leach worked quite fast, it stripped gold in under a minute. It is actually easy to observe when stripping is done, sometimes when unsure use wash container with a little distilled water. When you see gold is gone then it is done and you can move on another piece or batch. 
I used 2 containers I made for my crude demonstration. They were bottom part of a plastic bottle where I put a few hundred holes with a hot screwdriver. I put one in - it was moving up and down in leach and while I prepared - filled other one first one was done stripping so I took it out and put second in main leach solution. Then by the time I washed stripped material in my wash container and refilled it with another batch second one in main solution was done stipping. Sometimes I could not keep up as I only put few items in for stripping to make sure leach will get to all parts and strip everything. 
You can use stir plate - then you will not need motor to move material up and down just hang it is a basket or small fishnet bag so material is suspended in solution but stir bar is working so solution is agitated and flowing all around your material. 

I used ascorbic you can get in any health shop or gym or ebay. I estimated up to 2 grams of gold in solution (that was over-optimistic) and used double of that of ascorbic. 

To rejuvenate I added couple drops of lye to raise ph and added 32% strong peroxide in small increments with dropper while stirring solution. I also added about 2g of iodine to solution to compensate for iodine lost in wash water container.


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## patnor1011 (May 24, 2020)

And I have to add that I can not take credit for this process as I was just following what other members did before me - they may have more experience and could post their input to how to use this leach the best. Kudos to owltech as I was inspired mainly by his videos.


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## patnor1011 (May 24, 2020)

If you want cheaper and fast process, and have larger objects (larger than pins) you need to check this post made by ION 47:
https://goldrefiningforum.com/phpBB3/viewtopic.php?f=86&t=28686

This is my attempt to recreate process he mentioned there.

[youtube]https://www.youtube.com/watch?v=ZVbX6VIFcNg[/youtube]


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## Lanec84 (Jun 2, 2020)

Kurt,

Registration with the DEA is for manufacturers and distributers of listed chemicals. End users of the chemicals only have to provide information and provide proper ID. For example, a local pharmacy sells Codeine cough syrup OTC. However, if you try to buy more than two bottles within a 30 day period (I think this is the right amount and timeframe) you will not only be turned away, but you can expect a visit from law enforcement. So as long as you show a legitimate use for the iodine you are purchasing, it shouldn't be an issue. Unfortunately it has the same implications as obtaining acids. Wholesalers want federal or state business tax ID numbers so are exempt from collecting retail sales tax. And they don't ship to residential addresses. Just my two cents.

Lane


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## Lou (Jun 2, 2020)

I2 leach can also be used with organic solvents, including DBC. 

The gold is recovered by boiling wherein the iodine sublimates, AuI3 decomposes and metallic gold left behind.


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## rickzeien (Jun 2, 2020)

Lanec84 said:


> Kurt,
> 
> Registration with the DEA is for manufacturers and distributers of listed chemicals. End users of the chemicals only have to provide information and provide proper ID. For example, a local pharmacy sells Codeine cough syrup OTC. However, if you try to buy more than two bottles within a 30 day period (I think this is the right amount and timeframe) you will not only be turned away, but you can expect a visit from law enforcement. So as long as you show a legitimate use for the iodine you are purchasing, it shouldn't be an issue. Unfortunately it has the same implications as obtaining acids. Wholesalers want federal or state business tax ID numbers so are exempt from collecting retail sales tax. And they don't ship to residential addresses. Just my two cents.
> 
> Lane


I broke my back 6 years ago and required narcotics for pain. Fast forward to a few months sga and my dentist gave me a script for a pain killer. 

When I went to have it filled the pharmacist refused because she said the DEA had two files on me. One in Florida where I used to live and one in South Carolina where I am now. 

Had to sign an affidavit that I was no longer in Florida. By the time it cleared I no longer needed the pain relief. 

Point is the DEA does keep records on Individuals. I don't know what the threshold for chemicals is but I am sure it could be low for precursor chemicals.

That said I have purchased Iodine crystals and Ki from Ebay. Both in small quantities. 

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## bvdsluis (Jun 3, 2020)

Hi Patnor,

Thanks for this very informative thread. I'm long time reader on this board and still only collecting material but not ready for refining. 
When the time is there I will start. The time will be ready when I have done enough study and reading and have collected enough material to work on. 

Enough about me, I have a question. I have also seen a thread from you about Eco-Goldex E Series (years ago) and this Iodine leach reminds me to that thread . How do you compare/feel about both methods on processing plated items in terms of:
Availability in Europe (I believe you live in Europe).
Price.
Precipitating the gold, how do you check there is gold in solution left?
Known pitfalls?
I remember you were very positive about Eco-Goldex E Series. I ask this because I see several options to process plated items but more options makes it harder to decide what is the best way for me. I stay in Holland and have to keep in mind what is there available and what not and that will be part of the decision. 

Thanks for your time,
Bob


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## galenrog (Jun 3, 2020)

Did you happen to notice the thread right below this thread? “Eco-Goldex” is in the title. Give it a read. 

Time for more coffee.


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## patnor1011 (Jun 4, 2020)

bvdsluis said:


> Availability in Europe (I believe you live in Europe).


Both processes chemicals are available and can be bought on ebay for example.



bvdsluis said:


> Price.


Iodine leach is more expensive however can be reused couple times so the price is lower considering few runs out of one leach despite initial investment. But even while it is more expensive the price still is not extraordinary. 
Secondly, I think there was some sort of consensus reached in our discussions at that time that there is no need to go for ecogoldex of any series as it is basically ferrocyanide leach and whatever it does it can be done with straight ferrocyanide without the hassle of dealing with other chemicals present in ecogoldex. Ferrocyanide can be bought quite cheap.



bvdsluis said:


> Precipitating the gold, how do you check there is gold in solution left?


I am not formally educated in chemistry but I am quite confident that when I drop gold out of iodine and solution is clear that pretty much mean there is no gold left in solution. I may be mistaken but then if some of the gold remains it is going nowhere as solution is going to be reused.



bvdsluis said:


> Known pitfalls?




Ferrocyanide or ecogoldex require delicate balance of UV light, oxidation and PH level. It works but it will take some time to master it and for me personally based on my experiments iodine is much faster. I mean really faster. What I observed though is that reused solution is a little less selective and dissolved gold but also nickel layer. I need to play with it a little longer and find out if a little addition of either iodine or iodide will make a difference. (I think it should)
Couple of weeks ago I did some experiments with ferrocyanide and while it worked it was painfully slow. There was not much of sun and while it worked it was really slow. My other experiments with ecogoldex where much faster but still slow compared to iodine. I literally could not keep up with removing stripped material, washing it and putting in new. I do not experienced any pitfalls with iodine yet so only time will tell.



bvdsluis said:


> I remember you were very positive about Eco-Goldex E Series. I ask this because I see several options to process plated items but more options makes it harder to decide what is the best way for me. I stay in Holland and have to keep in mind what is there available and what not and that will be part of the decision.
> 
> Thanks for your time,
> Bob



I have nothing against ecogoldex but knowing that it is basically the same as ferrocyanide leach I see no reason to use it when you can get ferrocyanide and use just that. Compared to iodine well gold drop is pretty easy and straightforward with no need to go through extra steps and procedures which ecogoldex require.


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## bvdsluis (Jun 4, 2020)

Hi Patnor,

Thanks a lot for your comprehensive and clear reply. This is what I was looking for and I hope this will benefit other readers as well. 

Kind regards,
Bob


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## Pierre2laps (Jun 16, 2020)

Hey Patnor,

I tried your iodine/iodide solution. It worked pretty well. I have now a solution cotaining 600mg/L of gold.

The problem is to drop gold with ascorbic acid. I introduced about 7 g of AA (I read a publication which said that AA/Au molar ratio of 15 is optimal) but nothing happened. I do not have a clear solution as yours. Any idea ?

Best regards,


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## Pierre2laps (Jun 16, 2020)

Re : I'm sure the problem is that my solution is too much I and KI concentrated but I used the same amount of KI and I than you. I'm really suprise you obtained a really nice clear solution with all the iodine there.


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## patnor1011 (Jun 18, 2020)

Add more ascorbic to it.
Stir in more till it dissolves and then leave it to sit overnight. Your gold should be settled on the bottom.


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## Pierre2laps (Jun 18, 2020)

It worked, thank you very much !


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## Owltech (Jun 18, 2020)

SMB can be used too


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## Tquilha (Jun 21, 2020)

This is a very interesting process and I'll be trying it for sure in the near future.
If anyone is interested, I found this paper on iodine leaching of electronic waste: https://dl.uctm.edu/journal/node/j2017-2/22-16_106_L_Lucheva_326_332.pdf

Could this work on gold bond wires after crushing ceramic CPUs?


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## philddreamer (Jun 22, 2020)

So, when ascorbic acid is used to precipitate the gold from the Iodine solution, the solution can be rejuvenated…

When SMB (sodium metabisulfite) is used to precipitate the gold, can the solution be rejuvenated, and how?

Thank you!
Phil


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## Owltech (Jun 23, 2020)

In the same manner - by using H2O2


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## Pierre2laps (Jun 24, 2020)

Does anyone know the amount of plated gold jewels which can be treated with one liter of this solution (ratio 10:4:1) ?

Does one liter is enough to treat 1 kg of gold plated jewels ?


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## Slochteren (Jun 24, 2020)

I tried it on gold plated silver, that made a mess, it also dissolves silver

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## philddreamer (Jun 24, 2020)

Thank you, Owltech!

Phil


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## patnor1011 (Jun 25, 2020)

When rejuvenating solution add peroxide in small increments. Slow. 
It is exothermic reaction which produces heat.


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## patnor1011 (Jun 25, 2020)

Owltech said:


> SMB can be used too



Will SMB or ascorbic drop also silver from solution or something else is used to drop silver?


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## rickzeien (Jun 25, 2020)

patnor1011 said:


> When rejuvenating solution add peroxide in small increments. Slow.
> It is exothermic reaction which produces heat.


How do you know how much to add. Do use 32 or 35%. Is their a reaction or something else that indicates you have added enough to indicate it is rejuvenated?

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## patnor1011 (Jun 25, 2020)

I would say that you will see when there is enough. If you will be adding in small increments, like couple ml at a time and stirring you will see it changing back to violet dark colour. 
That is also why small increments are preferable you will see when there is enough. 
Do not be impatient as adding more will make solution to become way too hot. 
I also do have full strength peroxide and I have used it but as I said - be careful and do it slowly.


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## rickzeien (Jun 25, 2020)

patnor1011 said:


> I would say that you will see when there is enough. If you will be adding in small increments, like couple ml at a time and stirring you will see it changing back to violet dark colour.
> That is also why small increments are preferable you will see when there is enough.
> Do not be impatient as adding more will make solution to become way too hot.
> I also do have full strength peroxide and I have used it but as I said - be careful and do it slowly.


Excellent. Thanks 

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## Owltech (Jun 26, 2020)

patnor1011 said:


> Owltech said:
> 
> 
> > SMB can be used too
> ...





https://patentimages.storage.googleapis.com/e5/84/46/7a0d7c23402d8c/US5137700.pdf


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## Yggdrasil (Jul 1, 2020)

Thanks Owltech 
I have been reading this patent document. 
So I'm thinking the Ammonium Iodide seems like the best route for most of us.
Hydrazine hydrate is not a very benign chemical to work with, and it may or may not be hard to get hold of.
So even if the Hydriodic acid route seems good with respect to the lack of chemicals introduced it may be expensive and difficult for most.
Ammonium Hydroxide is easy to find and then it is only the Hydrogen Peroxide and Iodine which should be easy enough, at least for me.
The leaching for the Ammonium Iodide is done at near neutral conditions and are less prone to dissolve base metals. And when the Iodide is sufficiently "polluted" it si just to drop the Iodine out and regenerate.
At least as I have understood it so far.
Are there anyone here with experience withe the Iodine/Ammonium Iodide leach that can confirm or not, this for us?


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## philddreamer (Jul 3, 2020)

I was able to purchase Iodine prills and Potassium Iodide crystals on e-bay... so I plan to run a test batch this weekend. I will saturate the solution until no more gold will deplate... I will post results! 
I have been doing some searches and been gathering more great information... 
this old thread help me a bunch:
https://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=127&p=2701&hilit=Iodine+7%25+Leach+for+Gold#p1007

Thank you!
Phil


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## Yggdrasil (Jul 3, 2020)

Looking forward to your results.
But within the topic, has anyone tried Amonium Iodine?
BR Per-Ove


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## philddreamer (Jul 4, 2020)

As I review the information I've collected, and a post from Lazersteve in this thread:
https://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=127&p=2701&hilit=Iodine+7%25+Leach+for+Gold#p1007


> Here are some ratios I came up with from a University Document :
> 4g:2g:10ml - KI:I2:H2O Hot (70C) 280 nm/min
> Steve


that means, according to those documents, if we use 300ml of distilled water... then we would need 120g of Kl: and 60g of I2. :? ...decisions, decisions!!! 

Some input... please!  

Phil


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## rickzeien (Jul 4, 2020)

philddreamer said:


> As I review the information I've collected, and a post from Lazersteve in this thread:
> https://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=127&p=2701&hilit=Iodine+7%25+Leach+for+Gold#p1007
> 
> 
> ...


Phil,

From Patnor " Rick. I used in my video 300 ml od distilled water 25g of iodine crystals and 100g of potassium iodide"

It works in those ratios. Have only done a small test but it works.

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## philddreamer (Jul 4, 2020)

Hi Rick!
That's the ratio I'm ready to use... 
but knowing what was posted by lazersteve, and the info on the old thread, I was wondering if adding extra iodine would help dissolve the gold faster. In one of Owltech videos, he seemed to have a bit of problem dissolving the gold, so he added more iodine and it speeded up the dissolving. 
I'm just trying to "start on the right foot"! :mrgreen: 

Thanks, Rick!

Phil


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## rickzeien (Jul 4, 2020)

philddreamer said:


> Hi Rick!
> That's the ratio I'm ready to use...
> but knowing what was posted by lazersteve, and the info on the old thread, I was wondering if adding extra iodine would help dissolve the gold faster. In one of Owltech videos, he seemed to have a bit of problem dissolving the gold, so he added more iodine and it speeded up the dissolving.
> I'm just trying to "start on the right foot"! :mrgreen:
> ...


When I did a test I swished a couple of ram sticks with the gold fingers still on and it dissolved in about a minute. You could try something similar before you change the ratios. 

I will be doing more test soon. From what I have read as long as you have free iodine and are below 7 PH it is supposed to work. 

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## Yggdrasil (Jul 4, 2020)

According to before mentioned patent document the ratio in a Iodine - potassium Iodide etchant is:
1-4-10 with respect to Iodine - Iodide - water and it should be quite acidic if my memory serves me well.
The worst with respect to base metals are the Hydriodic acid leach which is around 0-1 in Ph
The Ammonium Iodide leach should be done between 6.8 to 7.6 and is quite benign with respect to base metals.
It is also quite easy to prepare new Iodide from precipitated Iodine.


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## philddreamer (Jul 4, 2020)

I started a batch using Patnor's recommended ratios. The Iodide crystals dissolved readily, the Iodine prills about 10 minutes.





...so I placed another pound of assorted plated material... done in 10 minutes!

I have a light grey sediment, so I'm letting it settle; then will filter and precipitate w/ascorbic acid.



to be continued!!! :mrgreen: 

Phil


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## Yggdrasil (Jul 4, 2020)

Nice.
That is the recommended ratio for I - KI and I - HI solutions.
You are using ordinary vitamine C pills and crush them or dissolve them?


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## philddreamer (Jul 4, 2020)

Thanks, Bro!
I'm planning Vitamin C, though, I can use SMB. Restore with Peroxide and a couple grams of Iodine prills.

I plan to crush and add the powder... I'm used to do the same with SMB.
Plus, I don't want to add too much water when I rejuvenate the solution.


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## philddreamer (Jul 4, 2020)

After filtering the solution, I separated in halves; I tried Ascorbic acid on the left and SMB in the right.
Here are the results:


After 15 minutes of stirring, no visible results with the ascorbic.

I proceeded to add SMB to the beaker on the right... quick change in color; and after stirring, gold started to precipitate in a little over one minute!





Will check the results in the morning.


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## philddreamer (Jul 4, 2020)

Another note:
The gold, "dropped" with SMB, finished settling after 3 hours. I couldn't wait for the ascorbic to do its thing in the left beaker, sooo... I Cheated, and added SMB to it! :mrgreen: 
The gold has precipitated, and is 80% settled.

I ran this batch because I had to find out how much gold can be dissolved with a 300ml of solution, 
that way, I'll decide if it's worth the while for me to process about 100 pounds of pins and connectors using the Iodine leach. I ran 2.25 pounds of pins before the solution was saturated. 
It took a little less than 10 minutes to de-plate the first pound; another 5 minutes to decant the solution, and place another 1.25 pounds in the beaker; poured the solution. Another 10 minutes, and the second batch was done! 
I tested the solution to see if it was still "hot" but the item did not de-plate, so I believe the solution was saturated.
Guesstimating from the gold settled in the right beaker, I might be able to recover 3g... we'll see.


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## kurtak (Jul 5, 2020)

Just wanted to say thank you to everyone contributing to this thread :G 8) 8) 

Its "really good" to see a discussion going on about a process different from the so to speak "norm" of processes discussed :mrgreen: 

So thanks Pat for starting this thread - as well as the contributions of Rick, Yggdrasil, Owltech, etc. 8) 

And Phil - Sooooo cool to see you pop in on this one --- reminds me of the good old days 8) :mrgreen:

Since my move I don't really do much any more - might just have to go looking for some material to play again :mrgreen: 

Kurt


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## rickzeien (Jul 5, 2020)

kurtak said:


> Just wanted to say thank you to everyone contributing to this thread :G 8) 8)
> 
> Its "really good" to see a discussion going on about a process different from the so to speak "norm" of processes discussed :mrgreen:
> 
> ...


Come on in Kurt the water is fine...[emoji23][emoji1787][emoji16]

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## Yggdrasil (Jul 5, 2020)

I completely agree Rick.
We have nice comfortable water here  
The only sharks we have here do not eat people anyway :mrgreen: 
No pun intended Shark :wink: 

Back to the topic, this is the kind of threads I really love.
When we combine forces and delve into the ocean of knowledge amongst our esteemed members and discover new/old things in new/old ways as a group.
The Iodine leach has been sitting in a hidden dusted down corner of my brain waiting to get out, since I first heard about it.

And then Pat opened this thread and the nuggets of knowledge just materialize 
For me the main eyeopener was the patent document Owltech posted.
So I think the thanks should go to the ones that has done the testing, I'm just reading back my findings in the document.

In my eyes this is the kind of discussions that makes this forum so valuable.
Thanks to all the contributors, past and future.
If we can ignite enough interest to lure some of our dignified members back into the art again, even better  :lol: :mrgreen:


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## philddreamer (Jul 5, 2020)

> Just wanted to say thank you to everyone contributing to this thread :G 8) 8)
> 
> Its "really good" to see a discussion going on about a process different from the so to speak "norm" of processes discussed :mrgreen:
> 
> ...



Thanks indeed, to all! 

In the last year and a half, I haven't done much processing either... I've been a bit burned out, so doing some resting; also recovering from a couple of surgeries to repair hernias, and my right knee. 
I always like to check in, though,... and when I read about Pat's iodine testing, I said to myself, " I gotta try this"! :mrgreen:


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## Yggdrasil (Jul 5, 2020)

Just what I said, another bonus on top of the icing of the cake   :mrgreen:


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## philddreamer (Jul 5, 2020)

> I completely agree Rick.
> We have nice comfortable water here
> The only sharks we have here do not eat people anyway :mrgreen:
> No pun intended Shark :wink:
> ...



I, for one, have been wanting to find an easier and safer way to de-plate gold... I've used the sulphuric cell successfully, but we all know its dangers... and it can be messy! 
Pat's presentation made it look so safe, and simple, that I just needed to give it try. 
So far, so good! Knock on :G :mrgreen:
I know that we'll all be able to end with a very detailed, and safe way to use this process!

This great Forum has the minds! 8) ... uhhhh, speaking of great minds,  
I'm trying to rejuvenate the solution, but after adding about 20ml of peroxide, no change in color, other than when I add it.
So, my question is: after running 2.25 pounds of material thru the 300ml solution, the iodine was depleted? Can the solution be rejuvenated? 
I've read that in some of the other tests, only a few items were deplated... maybe there was enough free iodine left, and that's the reason why it was rejuvenated!?

Thank you kindly!


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## rickzeien (Jul 5, 2020)

philddreamer said:


> > I completely agree Rick.
> > We have nice comfortable water here
> > The only sharks we have here do not eat people anyway :mrgreen:
> > No pun intended Shark :wink:
> ...


When I rejuvenated mine I added 32% H202 drop wise. Each time I added it the solution would turn to a cloud of red as the drops entered the solution. I kept adding g slowly until it was back to it original color. 

I added it faster on a second time and it was very vigorous to the point of almost "boiling" over the top of the beaker. It was a very hot reaction so I would use caution when adding the peroxide and use a catch basin. 

The literature I read said you could recover the iodine by adding even more H202 and the filtering out the elemental iodine. (I have not tried this yet but it is on my to do list)

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## Yggdrasil (Jul 5, 2020)

Again pr the document and the forum:
It can be rejuvinated but it is recommended to not do it too many times.

Since the I2 - KI leach is acidic, it will pick up base metals which will make it less effective over time.
Just add 30% H2O2 slowly with stirring untill it have restored the deep brown color.

If you add 3% H2O2during the leach, it will leach significantly faster but it should be done at the bottom of the liquor so it will generate O2 bubbles through the liquor. 
Which makes me think... How about an air pump like AP???

When it becomes too contaminated, you add 30% H2O2 with stirring untill all the Iodine has precipitated out.
It shall then be rinsed in HCl or Nitric and De Ionized water and it is ready to make up a new mix.

PS!
Rick beat me to it :lol:


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## rickzeien (Jul 5, 2020)

Yggdrasil said:


> Again pr the document and the forum:
> It can be rejuvinated but it is recommended to not do it too many times.
> 
> Since the I2 - KI leach is acidic, it will pick up base metals which will make it less effective over time.
> ...


The HCL wash is a new item for me. Thanks. 

I also prepared a leach with just KI and HCL and added a small amount of 32% H202. 

I used 50 grams KI and 50 ml of HCL in 250 ml DI water. (Distilled would work as well of course) I used 3 ml of H202. 

It seemed to strip as well as using the elemental iodine and KI. I am concerned it may be more aggressive to base metals so I am going to do some trials of base metals only. I ordered some copper, nichol and carbon steel foils to test. 

I will report here when I get the results. 

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## Yggdrasil (Jul 5, 2020)

The HCl or Nitric wash is to clean the Iodine after it have been dropped out of the dirty Iodide solution.
The document uses the phrase "mineral acid" so I guess HCl might be the goto solution for most of us.

I'm going to test Ammonium Iodide because then I'm not confined to buy new KI.
I will then just generate the NH4I needed by adding NH4OH and H2O2 to the I2.
That is my plan at least :wink: :mrgreen:


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## philddreamer (Jul 5, 2020)

> rickzeien wrote:
> The literature I read said you could recover the iodine by adding even more H202 and the filtering out the elemental iodine. (I have not tried this yet but it is on my to do list)


Well, I only have 12% H2O2, so I must have been too generous, and added extra H2O2, because the solution turned very brown and there're chunks of "something" floating, and at the bottom! :shock: 
Is that my extra iodine that I'm supposed to filter out!?



> Yggdrasil wrote:
> If you add 3% H2O2during the leach, it will leach significantly faster but it should be done at the bottom of the liquor so it will generate O2 bubbles through the liquor.
> Which makes me think... How about an air pump like AP???


In the old Iodine thread Gold-Digger seemed to find out that ,that's not a good idea!
https://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=127&p=2701&hilit=Iodine+7%25+Leach+for+Gold#p3217



> rickzeien wrote:
> I also prepared a leach with just KI and HCL and added a small amount of 32% H202.
> 
> I used 50 grams KI and 50 ml of HCL in 250 ml DI water. (Distilled would work as well of course) I used 3 ml of H202.
> ...


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## rickzeien (Jul 5, 2020)

I think so. Filter them and rinse. I believe elemental iodine is a blue/gray color. 



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## rickzeien (Jul 5, 2020)

Iodide chrystal image






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## Shark (Jul 5, 2020)

Thanks everyone, I have been interested in this since owltech did his first videos of it. I have a growing pile of plated jewelry and hate to use the sulfuric cell right now due to other things keeping me busy. Maybe at a later date I can actually give it a try.


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## Yggdrasil (Jul 6, 2020)

The quoting was a bit strange so I'm not sure whom to adress.
But anyway here it comes:


> I did a search on NH4I prices and they're 4 to 5 times more expensive! :?
> For now, I'm sticking with KI



From the document:


> An aqueous solution containing 400 gms of ammonium iodide was prepared as follows:
> (1) 500 ml of de-ionized water was placed in a 2-liter beaker.
> (2) 351 gms of iodine were added.
> (3) 47 gms of hydrogen peroxide were added and stirred.
> ...



Specifically this:


> (3) 47 gms of hydrogen peroxide were added and stirred.
> (4) 97 gms of ammonium hydroxide were slowly added and stirred until all the iodine dissolved.



So one do not have to buy Ammonium Iodide if one has access to 30% H2O2, which one should have anyway, when running an Iodine- Iodide leach.


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## rickzeien (Jul 6, 2020)

Is the percentage of ammonium hydroxide specified?

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## Yggdrasil (Jul 6, 2020)

Rick.
So far I haven't found any reference to the strength.


> The ammonium iodide is prepared by adding elemental iodine to water, then adding 30% hydrogen peroxide and finally adding slowly, and with stirring, a solution of ammonium hydroxide.
> Iodine is barely soluble and barely reacts with an aqueous solution of ammonium hydroxide. However, it readily dissolves in and reacts with the ammonium hydroxide when hydrogen peroxide is present.
> The ammonium iodide that forms is readily soluble in the aqueous solution.


So since it was referenced as an aqueous ammonium hydroxide I kind of assumed it to be sufficient with 15% household brand.
But then again assumptions is the mother of all f... .ps.

Here is the link Owltech posted:



> Re: Iodine leach
> 
> Post by Owltech » June 27th, 2020, 5:19 am
> 
> ...


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## rickzeien (Jul 6, 2020)

Thanks

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## patnor1011 (Jul 6, 2020)

I have found that after I drop gold from first iodine-iodide solution and rejuvenated it I left it to stand in a closed bottle - it developed some white/yellow/gray crust towards the bottom of the bottle. I decanted iodine solution to another bottle and kept this crust-crystals in bottle where they formed. 

I used this rejuvenated iodine solution to deplate gold and found that it is not as fast as the original solution, I need to find out why. 

I am thinking that I will try to extract iodine after every use and make a fresh leach solution every time. According to patent owltech posted 1l of this leach should hold up to an ounce of gold. Extracting iodine and making iodide from some of it to create fresh leach every time is more time consuming than simply rejuvenating, I need to play with this some more to figure out what may be the best solution.


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## Owltech (Jul 7, 2020)

https://www.mdpi.com/2075-4701/9/3/363/htm


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## Yggdrasil (Jul 7, 2020)

Pat
I believe the crust is precipitated/crystallized base metal salts and the reduced efficiency of the leach are caused by increasing amount of base metals in the solution.


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## kurtak (Jul 7, 2020)

rickzeien said:


> Come on in Kurt the water is fine...[emoji23][emoji1787][emoji16]
> 
> Sent from my SM-G950U using Tapatalk



:lol: :lol: :lol: 

Thanks for the encouragement - but the problem is not jumping in to give it a go - the problem is not having material to jump in on

When I made my move I brought a trailer load of higher grade material with me & last year I went through the trailer & pulled out the vast majority of the plated stuff & processed it - got 52 grams out of that run - if I dug "deep" back into the trailer I "might" come up with another pound of plated material - just not worth chasing for a gram or two

Where I now live there just is not a lot of material available because grant county (which is like the 4th or 5th largest county in Oregon) only has about 7,500 people in the county (there is only one stop light in the whole county) so finding scrap is hard to even find - the county is like 70 - 80 % national forest

I do have like 60 - 70 pounds IC chip I hope to process this year but that's an incinerate/smelt process

As well I have a few hundred pounds of HIGH chip pop boards - but again - those are an incinerate/smelt process

Also have a few hundred pound of some "good" silver recovery stuff (contact points)

Just don't really have any (or much) gold plated to play with  - or I would certainly jump in to play :mrgreen: 

That all said - I sure am enjoying watching you all play :G :mrgreen: 

Kurt


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## patnor1011 (Jul 7, 2020)

I wonder (and will try this) if this is not a way to get silver out of keyboard mylar sheets. I have saved up about 15 kilogram of them. Seems like a next project but I will have to find a way to get hydroxylamine


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## patnor1011 (Jul 7, 2020)

Yggdrasil said:



> Pat
> I believe the crust is precipitated/crystallized base metal salts and the reduced efficiency of the leach are caused by increasing amount of base metals in the solution.



That is what I thought so that is why I think that I will remove iodine and start fresh after every use, or every other one.


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## philddreamer (Jul 12, 2020)

I finally had some time today and melted a .2g buttom...  … I think I dissolved more base metals than gold. So, I've been doing some reading and I found this:
https://www.sciencedirect.com/science/article/abs/pii/0304386X9190029L
which reads:


> Several oxidants (hypochlorite, iodine and hydrogen peroxide) were used to evaluate the dissolution of gold in iodide electrolytes at ambient temperatures. Evans diagrams constructed for the two half cells involved in the dissolution process show that hydrogen peroxide is not a suitable oxidant for the iodide system.
> The gold dissolution rate in an iodine-iodide mixture is dependent upon the concentration of iodide, iodine and the solution pH. An optimum iodine-iodide mole ratio of 0.35–0.4 was found for 0.1 M KI solutions, with pH ranging from 2.7 to 11.5; these are capable of dissolving gold at a maximum rate of 17 mg/cm2h.
> If a small addition of hypochlorite is made (< mM for 0.1 M KI solutions), gold will be dissolved faster than with iodine as oxidant. However, the gold dissolution rate in a hypochlorite-iodide mixture is strongly dependent upon the solution pH. The optimum hypochlorite-iodide mole ratio is 0.25 for KI solutions of 0.02 to 0.1 M at pH 2.7.
> Cyanidation, using the same concentration of cyanide yielded gold dissolution rates within the range of 1.3 (at pH 12.5) and 3.5 mg/cm2h (at pH 8.5).


I'll make another batch and check the pH, and maybe bring it to pH6 (or higher) if need be!? 
Maybe then, it will dissolve more gold and less base metals!?
Just wondering... :|

Thank you!
Phil


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## patnor1011 (Jul 13, 2020)

Key here may be in using uniform stock. Like if the material is the same it is easy to observe when gold is dissolved and material can be removed before any significant amount of base metals start dissolving. Also agitation. When I did it I used smaller amount of material going up and down in solution. THat way it was all exposed more or less equally. 
I would love to try like 5l of solution in a RVEC. :mrgreen:


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## philddreamer (Jul 13, 2020)

patnor wrote:


> Key here may be in using uniform stock.


I just started doing that last night...  while looking for more material to process, I came across 11 pounds of the same material, so I've been sorting it, and prioritizing... which one will be processed first and so on!
I still would like to know, though, that if by adding some lye and bringing up the pH, if that would help keep base metals from dissolving too readily... :|

phil


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## patnor1011 (Jul 15, 2020)

Don't know Phil all we can do is to try 
I picked up 50 laptops so when I tear them apart I will have some more material to experiment with.


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## philddreamer (Jul 21, 2020)

Well, here's an update on my iodine leach process...
I made a new batch, I checked the pH = 6.7; so I added 2 pounds of low yield plated material, and it de-plated quickly; I decanted the solution and added another 2 pounds. As I swished the solution, the solution quickly became clear!!! :shock:
So... I thought, that means I de-pleated the iodine!? 
So I added some 12% peroxide, and the iodine color came back, BUT, that's when things went BLAHHH! :?
The solution started to foam up, so I added a bit of water, proceeded to decant the solution and add some SMB in order to drop the gold. 
The gold didn't drop, but the base metals did, resembling silver chloride, (though no silver was in material). :roll:
I suspected that the gold cemented, so I inspected the left over material and it seems so. 
I need to go back to the drawing board, sit down and evaluate things... :mrgreen:

Pat mentioned about the thio cell, is it this one?
https://goldrefiningforum.com/phpBB3/viewtopic.php?f=86&t=28686#p302362

phil


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## nickvc (Jul 22, 2020)

Phil what you experienced is very similar to what happens if you overload a cyanide solution which is very easy with plated materials as the leach prefers copper and nickel, so you strip the gold and it cements back out as it prefers to dissolve them, weak solutions are much more selective but also more time consuming and produces much more waste solutions.
I think you are going to have to play with your solution and different ph levels to find the optimum balance, I remember talking to our much missed GSP about this and also recall him saying he made good money buying other refiners stripped material and doing the job properly


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## philddreamer (Jul 22, 2020)

Nick wrote:


> Phil what you experienced is very similar to what happens if you overload a cyanide solution which is very easy with plated materials as the leach prefers copper and nickel, so you strip the gold and it cements back out as it prefers to dissolve them, weak solutions are much more selective but also more time consuming and produces much more waste solutions.
> I think you are going to have to play with your solution and different ph levels to find the optimum balance, I remember talking to our much missed GSP about this and also recall him saying he made good money buying other refiners stripped material and doing the job properly



Thanks, Nick! 
Yes, I'm afraid I have overloaded the solution...  It's obvious that we need to find a balance.
I have been thinking of diluting and/or raising the pH levels, then run some tests until we figure it.
Yeap, I miss Chris, too! 

I will be trying the thiourea/citric cell soon... lets see how that works out with big batches!!! 
I know, I know... "we donee no stinking baachess!" :mrgreen: 

phil


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## kurtak (Aug 2, 2020)

Ok - so recently I have had a couple people tell me they have "several" buckets full of black sands & asked if I could recover the "traces" of gold in the sands - these would be the traces remaining in the sands "after" other concentration methods (running the sands through a gold spinner &/or over a shaker table)

we know that even a shaker table or gold spinner does not get all the gold from black sands

So I am just wondering if iodine/iodide leaching the black sands would work to recover the traces of gold in the black sands ?

Hopefully Deano can chime in on any pros/cons 

out the gate I can likely get my hands on 10 - 15 buckets full & if it's a viable leach method I can likely get who knows how much more - being as where I live it's just a matter of putting the word out to get more

Kurt


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## Deano (Aug 2, 2020)

Most gold in black sands is present as free gold particles, it is rare for any quantity of gold to be locked up in the sands themselves.

As most of the black sands cons have been recovered by sluicing you are looking to gravity recover the gold by a system which is at least as efficient as a sluice system.

Most, if not all, of this free gold can be recovered by use of a table, provided the feed has been properly sized and the table is operated correctly, I had a section on tabling on my earlier thread.

The amount of gold which is not recovered by a properly run table is small enough that it is only viable to use cyanide as a leach system to recover this gold.

You can certainly recover any fine residual gold from table tailings with most gold leaches but it usually is not viable to do so due to the cost of running these leaches.

Most acid based or high redox leaches will also have a lot of the leach components lost in the digestion of the iron sands themselves, so you are looking at low redox or neutral to alkaline based systems to minimise reagent consumption.

My first approach would be to set up a properly made Wilfley type table and run feed which has been well sized, it is impossible to recover all < 50 micron gold from a coarse feed which has a higher inertial component.

Deano


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## DNIndustry (Aug 11, 2020)

Lou said:


> I2 leach can also be used with organic solvents, including DBC.
> 
> The gold is recovered by boiling wherein the iodine sublimates, AuI3 decomposes and metallic gold left behind.



I previously did this alot both KI and NH4I.
KI is very acidic is very hungry for base metals. NH4I is nearly neutral easy virtually no base metals 

1 gallon of this KI/I3 (depending on I2 concentration) can hold upto 4 ozt of Gold

Lou..
I believe that unless you use a some form of liquid cooled coiled condenser you are going to loose values. I know this for a fact. I have lost a decent amount For reference they use iodine to refine Titanium, Niobium, Halfnium, And a bunch of other metals as an Iodine gas. 
Chemical Mass transport
Van Arkel Deboer process

Any apparatus ideas?


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## DNIndustry (Aug 11, 2020)

Yggdrasil said:


> The HCl or Nitric wash is to clean the Iodine after it have been dropped out of the dirty Iodide solution.
> The document uses the phrase "mineral acid" so I guess HCl might be the goto solution for most of us.
> 
> I'm going to test Ammonium Iodide because then I'm not confined to buy new KI.
> ...




Look back through my old posts. You will find alot of what you will need.


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## DNIndustry (Aug 11, 2020)

House hold nh4oh is not the same. 
A
Has other ingredients if its the cleaner. 
Tech grade NH4OH is 28 to 29%. 1 gallon will last for ever

Make sure to follow directions on lingering smell if it occurs. Add h2o2 as delineated. 

I believe I used sulfuric for the regenerating. Have to look back.

Hydroxylamine hcl is on eBay. 

Don't forget you can do palladium platinum and rhodium as well.

I advise against the oxalic acid drop ....nano spherical metalic gold that glazes your beaker.

You will know if you cleaned the mud well when you melt an purple or blue smoke comes out. Your losing gold if so.


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## Lou (Aug 12, 2020)

Do not add ammonia (ammonium hydroxide) to elemental iodine!!


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## Yggdrasil (Aug 12, 2020)

Hi Lou.
Can you please elaborate a bit more?


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## patnor1011 (Aug 13, 2020)

Yggdrasil said:


> Hi Lou.
> Can you please elaborate a bit more?



It will produce highly unstable explosive nitrogen triiodide. That stuff if dried can be set off with a feather. 
I do not mind a bit of base metals in solution or to recover iodine after every leach and to start over. It is more labour-intensive but well offset any hazard of trying to use iodine with ammonia. 
I like the peace of mind when doing my stuff and as little hazard or problems as possible. To this day I am scared to go close to concentrated sulfuric or lye and I do not plan to add iodine leach to that list so no ammonia for me. :mrgreen:


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## Yggdrasil (Aug 13, 2020)

Aah I rest my case.
There was no such mention in the patent document.
Can this be counteracted by adding peroxide first or using a lower concentration ammoniun hydroxide?


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## DNIndustry (Aug 14, 2020)

The patent doesn't give the warning Lou does. 
It expects you to follow the directions explicitly. If you follow them it works wonderfully. 
Remember your reading a patent. Pretty sure the patent office reviews and checks the claims very carefully. 
They are not going to publish what not to do
Ammonium iodide it self is not flammable.


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## vav (Oct 10, 2020)

HI ALL

how do you exactly handle with rinsing water...do you evaporate ...or precipitate as main liquor...or use as another part of source of new batch
Thanks for your imput

vav


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## vav (Nov 4, 2020)

To DNIdustry
I have tried to send you PM but its stucked in Outbox don't know why,than I have to posted here

Amonium Iodine problem
Sent: November 3rd, 2020, 8:21 pm
From: vav
Recipient: DNIndustry 

Dear sir,

I am not completly biginer,some methodes like AP,AR,drop with even oxalic acid, Sulfuric cell etc. goes well for me and I alreday recovered little more than 110gAu after melting but
I would like to ask you to help me with my NH4I composition.Regarding patent this should be clear or whiteish solution.
I read all available wires here in GFR about this topic as well as patents you mentioned and see some videos...but
even when I follow the amounts of ingredients exactly I am not able obtain NH4I as clear solution,thus I cant add suplemental Iodine to form final etchin solution
I took for first try all in 1/10 ratio.
50ml DI H2O add 35.1g Iodine crystals
start stiring at magnetic stirer
add 4.7g H2O2 30%
stiring in 1 min. slightly red color
add 9.7g NH4OH 25% in 2ml portions by pipet,
after 3rd additons no more clear solution only dark brown even after all 9.7g spent
continuos stiring didn help even after 3 hours
and there is still undisolved residue of Iodine at the botom of beaker.
Even in this state without adding last portion of 10g suplemental iodine
the solution strips my finger from old ISA slot in less than minute,but I would like to understund what I did wrong especialy when NH4OH and Iodine is envolved.
ALL ingredients are lab. grade from Lachner company.
I would like to use this method because some mine material is not suitable for sulfuric cell like smal connectors with pins traped in plastic which cause problems in sulfuric...
Thank you in advance,and hope you will spend some time to help me
Jan
[email protected]


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## FrugalRefiner (Nov 4, 2020)

vav said:


> To DNIdustry
> I have tried to send you PM but its stucked in Outbox don't know why,than I have to posted here



Jan, your PMs stay in your Outbox till they are opened by the recipient. Then they move to your Sent folder. It's not an error or a problem. It's just the way the PM system works.

Dave


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## vav (Nov 4, 2020)

Tkanks a lot Dave
didnot remember this behavior of PM, 3 years ago I used last one


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## vav (Jan 5, 2021)

Hmmm...
That's a piti,looks like no one is wiling to help me.


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## Yggdrasil (Jan 5, 2021)

Have DNindustry read your PM?
I do not have any direct input to your questions.
But since it strips the gold it can be used as is, cant it?
Have you tried to precipitate the gold?

Edited for spelling error


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## FrugalRefiner (Jan 5, 2021)

DNIndustry last visited the forum October 7th, 2020.

Dave


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## vav (Jan 6, 2021)

Thanks Yggdrasil for reply

No, PM is stil unopened.

Yes strips the gold,but the place where thiknes of gold layer is thicker is covered with black sludge after deplating and rest of pin is nicely silver shining__nickel layer.
Also I have same problem like Pat had with WhiteGrey sediment in the bottle of rinsing water.Don't know how to redislove this resudue {HCl does not work} and thus separete it from precipitated gold.


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## FrugalRefiner (Jan 6, 2021)

Vav, I don't think it's that no one is _willing_ to help you. It's that most members have never tried it. I don't know if Patnor ever got it to work as he was hoping, and DNIndustry hasn't visited the forum in quite some time. If you try the process and work out the bugs, please let us know.

Dave


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## vav (Jan 6, 2021)

Thanks Dave,

For sure I will, onec I find the solutions of mine bugs.
Because everything I know about Recovery/refining I learned from ALL OF YOU here/
perheaps I will give small piece back to the forum later on.
Unfortunately I have no lab ,all I do outside at the garden,what is now impossible due to snow here,I have to wait at least for 10deg.C for my experiments to continue


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## FrugalRefiner (Jan 6, 2021)

We're in the grips of winter here too.

Stay safe when you're working outdoors. Winds can shift quickly.

Dave


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## rakno91 (May 1, 2022)

Owltech said:


> SMB can be used too


hello owltech 
1st timer needed help. i did my leaching 1:2:10 on gold plated pins got success in getting gold into solution.then i diluted caustic soda (10gms)into 15 ml distilled water and slowly added it into the solution stirred it well and left it for 10 minutes.then i dissolve 25gms of ascorbic acid in 20 ml distilled water and left it for overnight.nothing happened no gold drop no clear solution.can you suggest what to do now?


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## rakno91 (May 1, 2022)

rickzeien said:


> Phil,
> 
> From Patnor " Rick. I used in my video 300 ml od distilled water 25g of iodine crystals and 100g of potassium iodide"
> 
> ...


hello phil 
what will be the next step for the gold containg solution to drop gold first timer pls help i am stucked


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## Yggdrasil (May 1, 2022)

rakno91 said:


> hello owltech
> 1st timer needed help. i did my leaching 1:2:10 on gold plated pins got success in getting gold into solution.then i diluted caustic soda (10gms)into 15 ml distilled water and slowly added it into the solution stirred it well and left it for 10 minutes.then i dissolve 25gms of ascorbic acid in 20 ml distilled water and left it for overnight.nothing happened no gold drop no clear solution.can you suggest what to do now?


Why are you adding NaOH?


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## orvi (May 2, 2022)

rakno91 said:


> hello phil
> what will be the next step for the gold containg solution to drop gold first timer pls help i am stucked


Next time use directly SMB to the pregnant solution. It will reduce excess iodine back to iodide and simultaneously drop the gold.


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## rakno91 (May 2, 2022)

orvi said:


> Next time use directly SMB to the pregnant solution. It will reduce excess iodine back to iodide and simultaneously drop the gold.


can i use smb now??


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## rakno91 (May 2, 2022)

Yggdrasil said:


> Why are you adding NaOH?


for high ph level


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## orvi (May 2, 2022)

rakno91 said:


> can i use smb now??


SMB work only in acidic conditions. So I am not sure it will do the thing now. Ascorbic acid should work just fine for this - but you need to kill all residual iodine with it, and it takes some quantity of it. You should eventually see the solution to lighten in colour - iodine will be slowly reduced to iodides. 

If you fail to recover your values with ascorbic acid, acidify the solution with HCl and then use SMB.


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## rakno91 (May 2, 2022)

rakno91 said:


> hello owltech
> 1st timer needed help. i did my leaching 1:2:10 on gold plated pins got success in getting gold into solution.then i diluted caustic soda (10gms)into 15 ml distilled water and slowly added it into the solution stirred it well and left it for 10 minutes.then i dissolve 25gms of ascorbic acid in 20 ml distilled water and left it for overnight.nothing happened no gold drop no clear solution.can you suggest what to do now?





orvi said:


> SMB work only in acidic conditions. So I am not sure it will do the thing now. Ascorbic acid should work just fine for this - but you need to kill all residual iodine with it, and it takes some quantity of it. You should eventually see the solution to lighten in colour - iodine will be slowly reduced to iodides.
> 
> If you fail to recover your values with ascorbic acid, acidify the solution with HCl and then use SMB.


thanks orvi i will eventually try ascorbic acid again.but if i fail then i will acidify it wid hcl and then use smb.but how much hcl n smb should be used pls clarify.


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## rakno91 (May 2, 2022)

rakno91 said:


> can i use smb now??


and how much smb should be used and will it change its colour


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## Yggdrasil (May 2, 2022)

rakno91 said:


> for high ph level


????
Please explain. Why do you do a thing... 
you do a thing for a purpose, what is that purpose and why.


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## orvi (May 2, 2022)

You need acidic solution, take pH paper and add HCL till you get pH around 2 and less. That should be good enough. SMB is added to the point when reaction mixture clears up significantly (destroying iodine) and then a bit more (like a spoonful for dropping gold. I do not exactly know how much of the iodine was in.


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## rakno91 (May 2, 2022)

Yggdrasil said:


> ????
> Please explain. Why do you do a thing...
> you do a thing for a purpose, what is that purpose and why.


i just read it said so. although i had a very little knowledge of chemistry so as a first timer , considered it a step that i had to raise ph then i had to bring ph down with ascorbic acid for result


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## rakno91 (May 2, 2022)

orvi said:


> You need acidic solution, take pH paper and add HCL till you get pH around 2 and less. That should be good enough. SMB is added to the point when reaction mixture clears up significantly (destroying iodine) and then a bit more (like a spoonful for dropping gold. I do not exactly know how much of the iodine was in.


the solution was iodine1: potassium iodide 2:water10


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## 4metals (May 2, 2022)

Probably 30 years ago we used to get in drums of iodine etch solution which was used to selectively etch hybrid microcircuits. They were loaded with gold and simply adding KOH released the gold and regenerated the iodine to make KI which was used to make more etchant.


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## orvi (May 3, 2022)

4metals said:


> Probably 30 years ago we used to get in drums of iodine etch solution which was used to selectively etch hybrid microcircuits. They were loaded with gold and simply adding KOH released the gold and regenerated the iodine to make KI which was used to make more etchant.


Yeah, phase diagram is right about this, and of course, simply KOH will do the job. But I assumed he has base metals in there, which will precipitate as hydroxides and complicate the workup procedure. Not quite a problem, but filtering that could be painful.


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## manorman (May 3, 2022)

Yggdrasil said:


> Why are you adding NaOH?


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## manorman (May 3, 2022)

It sounds like he he adding NaOH inbthe wrong step, I believe it should be used after the gold is recovered using vitc or SMB. NaOH will recover the KI


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## 4metals (May 3, 2022)

Even if base metals were present, which they were not in the application I mentioned, they can be separated out after drying the precipitate and acidifying in Hydrochloric Acid which would likely re-dissolve the hydroxides leaving the gold as an insoluble. 
Of course every application is different and may present different hydroxide impurities, but the bottom line is the gold will be down and a little experimentation will show you the right path to purification.


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## rakno91 (May 4, 2022)

manorman said:


> It sounds like he he adding NaOH inbthe wrong step, I believe it should be used after the gold is recovered using vitc or SMB. NaOH will recover the KI


hi manorman 
can you guide me from step 1 to finale.the gold stripping material could be e waste,or the base metal may be copper or ss.thanks


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