Iodid-iodine still a reliable method?

[solar_plasma]

Now I've read hours for hours the posts about iodine for PGM-recovery and after I've succesfully tried the mainstream methodes, it sounds to me,that this is just the nicest one. Chemicals are no prob of mine and I love it's cold and slow style.

Are there any more complete and detailed descriptions,which I haven't foundt? Does anyone in this forum still use it?

 

[butcher]

There have been several long discussions on its use here on the forum, normally for leaching gold from ore.

 

[NobleMetalWorks]

There was a post that was removed, I believe because it was someone trying to promote the sales of a method used to recover gold, but it looked to me as if they were using an Iodine leach to recover gold from CPUs.

Once I am set up again I am planning on looking into it more, but at the moment I am just trying to get moved into my new location and set up. If anyone reading this is interested though, you can look up information on potassium iodide etching solution, and recovering Au from said solution. It seems that you can do so with a weak acid such as ascorbic acid, and a buffer such as sodium bicarbonate. Further more, you can also recover, and re-use the potassium iodide, thus reducing the cost of processing over a length of time.

When I was really actively investigating iodide leaching, I learned that it was actually a very well known and used method until cyanide leaching came along. Cyanide leaching was so good, and so inexpensive that iodide leaching was sort of abandoned. However, I believe for our intended purposes here on the forum, specially applying this older leaching technology to recovering values from e/i -waste, this method has a lot of value. Far safer and the ability to selectively digest only the Au and not base metals, for things like CPUs or pins, etc makes it a seemingly excellent leach solution.

Scott

 

[solar_plasma]

Interesting!

well...while I was sleeping and since I woke up,I'm thinking over, how to build a save DIY-sealed system for iodine-leaching, but each time I think of the neutralizing, storing and reusing of the waste (hopefully only as potassiumiodide),I can't help wondering, what iodine does to non-precious metals like tin. I've read, that tin reacts with iod forming tiniodide, which is poison and cancerogene. On the other hand, I read, that iodine-leaching is said to be highly selective. How can that be????

...but first I have to walk, before I run, so the next step will be a manually test with a smaller amount...

 

[NobleMetalWorks]

Interesting!

well...while I was sleeping and since I woke up,I'm thinking over, how to build a save DIY-sealed system for iodine-leaching, but each time I think of the neutralizing, storing and reusing of the waste (hopefully only as potassiumiodide),I can't help wondering, what iodine does to non-precious metals like tin. I've read, that tin reacts with iod forming tiniodide, which is poison and cancerogene. On the other hand, I read, that iodine-leaching is said to be highly selective. How can that be????

...but first I have to walk, before I run, so the next step will be a manually test with a smaller amount...

It's selective in certain cases so long as the PH is controlled.

I don't know enough to claim anything definitive, and I may or may not have overstated some things. I am trying to put my new location together and don't have much more time than making some posts, on this forum, to spend on this at the moment. Rather I am trying to point people reading this in the right direction if they wish to investigate this further, I will be once I have more time.

So if you are interested and looking for more information, you can google potassium iodide etching solutions, there is good information on how to recover from these types of solutions that might give you more information on how it might be done.

I'm sorry I'm not more help

Scott