An alternative passive stripping system

[DarkspARCS]

ok, um... I'm wondering about this OP telling us to "add water if solution goes clear to reconstitute the iodine solution".

My solution went from reddish brown to clear opaque like I said, in roughly 5 minutes. Following OP instuctions I added water: no reaction.

I remembered the method using h2o2 to create iodine cystals - so I added 1/2 cup h2o2 (NOT H2O) and the solution reconstitutionalised to a reddish brown.

so...

1. add a little HCL.

2. iodine reconstruction technique - h2o when it should have been h2o2.

 

[DarkspARCS]

ok. contents stripped, sitting on about 1/2 gallon of yellowish lixivant. there's a white grainy substance on bottom, I'm sure that it's the lye I previously added. how do I use the activated carbon? do I use it in an electrolytic cell? Do I heat the solution? Will cemetation work?

Do I need to filter out the lye? lol, there's so many different methods I've come across, this is your method, let us know how you use your charcoal.

 

[jimmyreece]

has anybody tried this with gold filled jewelry?

 

[DarkspARCS]

Activated Carbon took about a day of passive attention in lixivant agitation for it to completely turn the clear bright yellow fluid into a rich dark reddish brown iodine solvant... I'm assuming that the lixivant has been stripped by the activated carbon of values, thus leaving behind (basically, with geater volumn than originally used and possibly stronger iodine to water percentage) a viably reusable iodine solvant.

I've put the impregnated carbon into a large folgers crystals jar, which is filled about 3/4ths full. I'll need to ash it and smelt it to determine what I've got. I suspect a higher silver to gold ratio... as well as some pgm values from proprietary pcb smt stripped along with the flatpacks.

Jimmy... I will just say that this technique will cleanly strip G.F., As long as the gold is directly exposed to the iodine based solvant. Be patient as it will take some time. If solution loses its reddish brown color, add hydrogen peroxide to reconstitute the iodine.

Don't forget to add a small agitant of HCL to the iodine/ water mixture (4:1, water: iodine). if solution loses it's bite add additional shot of HCL 15% (Muriatic Acid). Don't forget to wear your P.P.E. and DON'T breath in fumes, wash exposed areas of skin splashed with solvant immediately, and ALWAYS....

ADD THE ACID TO THE WATER. =)

Capture values in solution with activated carbon (charcoal), ash, then smelt.

 

[jimmyreece]

do you feel adding some oxgen(small air pump) to the solution would speed the procss up a bit. and how essential is the use of activated carbon, would smb or similar be just as effective in dropping the values from solution and approx what is the ratio between values in solution and the stripped solids (foil) on the bottom of the solution?.......i apologize for the many questions, i am very eager to attemp this method , just seeing which way would be my best approach. thanks

 

[DarkspARCS]

basically, activated carbon is best in absorpsion of any pm values - esp. coconut charcoal meshes.

the air pump would serve to continuously agitate the solution through the material being stripped, speeding up the process time and making the solution work more efficiently.

 

[Irons]

Hello all,

Seems my first attempt at gold recovery was less than a stellar success...

Since I have no access to a fume hood and I live in a densely populated area, the Aqua Regia process would be very hard for me to attempt, so I decided to try out the iodine solution process.

So I attempted the experiment on a small scale to see if it works, and since iodine dissolves better in ethanol than H2O, I used that instead, but I decided to have a more concentrated mixture than recommended by the OP to see how fast it works.

In a small 50 ml flask, I added:
15 ml of Proviodine 7.5%
20 ml of ethanol 50%

Then I dropped a small piece of Pentium in the flask and I put a cork stopper on top. I let the mixture sit for over 48 hours, thinking that I would have my little pentium chunk stripped clean of gold, but to my surprise, the pins and the gold traces on the creamic substrate were totally unaffected.

So either I did something wrong, or the process itself takes a very very long time... The OP mentioned that he only used water and his mixture was just a "thin red color". My mixture was much more concentrated than that. So before attempting anything on a larger scale, I just wanted to ask the fine members of this forum who had success using this process if they have any recommendations, mixing ratios or suggestions they could share with me...

Robert in Montreal

You might want to check this .pdf out:

http://www.dim.esdm.go.id/makalah/2006_murakami_CCOP.pdf

 

[stihl88]

That links broken so try this one http://ebookbrowse.com/2006-murakami-ccop-pdf-d28345212
If you still cant get it to work then I'll upload a copy here.

 

[Irons]

That links broken so try this one http://ebookbrowse.com/2006-murakami-ccop-pdf-d28345212
If you still cant get it to work then I'll upload a copy here.

The original link works here in the US. 8)

 

[qst42know]

Does anyone know if DMG will extract gold from an iodine solution? Leaving the iodine in a reactive state?

 

[Irons]

Does anyone know if DMG will extract gold from an iodine solution? Leaving the iodine in a reactive state?

DMG is specific for Pd (acid medium) and Nickel (basic medium). It will not affect the Gold in the leach.

 

[qst42know]

Sorry Irons.

I was thinking of Dibutyl carbitol.

Will a solvent extraction work on an iodine leach.

 

[Irons]

Sorry Irons.

I was thinking of Dibutyl carbitol.

Will a solvent extraction work on an iodine leach.

The DBC is miscible in alcohol, so there would not be any phase separation.

http://en.wikipedia.org/wiki/Miscibility

 

[qst42know]

Is alcohol a necessary component of an iodine leaching solution?

 

[Irons]

Is alcohol a necessary component of an iodine leaching solution?

Good question. It will work to some degree. Iodine will dissolve in a solution of Potassium or Sodium Iodide. Try it and see.

 

[DarkspARCS]

I didn't use any alcohol. I haven't checked my charcoal yet, as I've been busy, but hopefully I succeed in seeing values when I do. Niether the OP nor the basement chemist (in his iodine leach version) mention alcohol.

United States Patent 5026420 doesn't use alcohol, but "a styrenic, strongly acidic cation-exchange resin, to selectively absorb and remove heavy metals from the lixiviant while allowing gold and iodine to pass through the resin" instead... I'm suspecting that they are referring to the use of corn syrup in that patent.

However, someone else used alcohol, so it's possible that the OP left that little detail out (like the other two items he left out, making alcohol the third item he left out...), and I'm sitting on worthless charcoal if he did.

I'm gonna be hot to trot if that becomes the case, because he would have ruined 3 months of hard work and 1000 grams of my produced materials...

 

[trashmaster]

No Dr. Williams did not use any alchol,,

 

[jimmyreece]

can someone explain to me what activated carbon is and how it is used in this process and can the pms just be filtered using standard filters

 

[Palladium]

Look in my sig line under chemistry handbooks to find more information on activated carbon.

 

[DarkspARCS]

Look in my sig line under chemistry handbooks to find more information on activated carbon.

Thanx Pal !