Eco-goldex CYANIDE Leach

[ettran]

hi , used zink powder , activated carbon , no results thus far. anyone have any results yet ? ed.

 

[patnor1011]

lets just talk about Eco-Goldex here please..

edit:
Patnor do you have some progress on this?

I do not have any way figured out how to ash carbon. I may try something but it may require some MacGyver improvisation. My original leach from what I stripped so far is stored with carbon in it but no way to move further on at this moment.

 

[Ali]

Hi everyone,

As far as I know best way to use carbon to adsorb gold from pregnant solutions is by circulating the pregnant solution or continuous mixing,for incineration it really needs oxygen, I've seen guys do it in big pan with blowers(pics), also I have came a cross a post in this forum talking about burning activated carbon http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=38&t=24511
[/attachment]

 

[Kilroy2k1]

Hi everyone,

As far as I know best way to use carbon to adsorb gold from pregnant solutions is by circulating the pregnant solution or continuous mixing,for incineration it really needs oxygen, I've seen guys do it in big pan with blowers(pics), also I have came a cross a post in this forum talking about burning activated carbon http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=38&t=24511
[/attachment]IMG-20160828-WA0045.jpg

I could be wrong, but the possibility of values floating away in the smoke from this method seem a little too high for comfort. I think something like an old Kiln for ceramics might be better suited to ash carbon.

Tom.

 

[Owltech]

Electric crucible furnace. If you can't afford it - make it.

 

[patnor1011]

Another video from ecogoldex, any thoughts?

[youtube]http://www.youtube.com/watch?v=E97dsVMYU_0[/youtube]

 

[frank-20011]

hello,

why they add NH3 (i thought eco goldex has an basic supplementarry) and why zinc stripes instead zinc powder?

regards!

 

[Mcnew32(Ag)]

A little update of my progress with eco- goldex E-series. Works very well.
Key factors are as follows:
1. Keep water hot (not quite boiling)
2. Keep solution in motion weather it be from a bubbler or some sort of storing device.
3. Always keep PH around 11-12 or close.

General info in my experience:
Day1. Used about 150g of eco-goldex powder to begin.
Added 1gallon of hot water to 5gal bucket. Stir still dissolved. Added about 4lbs of gold plated connectors from old nortel HF racks. Kept stirring for about 15 minutes the decanted solution into another clean bucket. Sprayed down connectors and picked out the ones that were not complete which were very few ( picture 1) Next I added about 80g of various pins from circuit boards, smaller connectors and various other plated items. I stirred for another 10 minutes. I noticed the dissolving was slowing so I added about another 100g of powder and stirred till dissolved. Another 5-10 minutes everything was deplated. Poured off solution washed materials and proceeded to add about 2.5 lbs of various slot connectors and cable ends and other contaminated connectors with plastic, solder and brackets on them. Stirred until the plating was dissolved. Took about 15-20 minutes of stirring. Noticed it was slowing a good bit so I added another 100grams of powder stirred until dissolved then added about 30 grams of fingers and about 1.5 lbs of mixed ceramic CPUs. I knew the solution was cooled off so I added another gallon of hot water And began to stir. When I added the CPUs and fingers it's wa already getting late I knew it was safe to leave the materials in the bucket over night. So I cleaned up and covered the bucket and left it overnight. Came back about 6pm the next day after work and poured solution into another container and picked through the CPUs and fingers. 95% of the fingers were deplated. Only maybe 50% or less of the CPUs were deplated. So I sorted out the finished fingers and cpus and left the rest to finish. Over night again. Note the solution is cooled and the CPUs are a lot heavier plated than fingers so will take quite a bit longer. The CPUs have been in solution for about three days now. Should be 100% complete tonight. I want to make sure that all of the free cyanide is used up so this is why I'm leaving material in for so long. I did notice that on the last couple decantings there was a little bit of black powder precipitate in the Bottom of the bucket. I will collect this when everything is complete and I do my filtering stage before I add zinc powder to the pregnant solution. I will update when I am in this stage.

 

[anachronism]

A few points if I may.

Some of your material still has gold on it. Be careful that you get it all off.
You appear to be using far far too much of the compound for the volumes of material that you are doing. You can also see where the copper has been leached.
Differing strengths have differing leach properties.
The ceramic processors still have gold underneath the chip dies.
You will not necessarily use up free cyanide just by leaving the product in there, and you can actually have the gold precipitate back onto the base metals that are exposed by trying to do this. I can see items on your photos that already have gold precipitated back onto them.
There's more to this type of leach than meets the eye, and although it's a promising start there's an awful lot more to understand and learn to ensure your get all your values recovered safely.

I hope that helps

Jon

Edit for spelling mistake

 

[FrugalRefiner]

Mcnew, I have to agree with anachronism that it sounds like you're using too much eco-goldex. Are you providing plenty of light during the process? From what I understand, the potassium ferrocyanide that is the active ingredient requires UV light to liberate the cyanide that dissolves the gold. If you expose it to UV light, the cyanide becomes available. If you put it in the dark, the cyanide recombines with the iron. At least that's how I understand it.

Dave

 

[upcyclist]

Is that gold I still see on the fingers? Would it make more sense to separate your source material a bit more and use different methods for different sources? Like copper chloride for fingers, Eco-goldex for pins, a little more pretreatment for ceramic chips, etc.

 

[Mcnew32(Ag)]

Thank you for the replies, after the pictures were taken I did sort out the parts that still have plating as well as the components that have some gold precipitation attatched. So all the material has since been sorted accordingly. You are right as I stated in my post there were some values precipitated in the bottom of the bucket but that will all be caught washed and re dissolved in AR later along with my other filters from the same process. Both of you are right about adding too much eco-goldex but i figured if I added more goldex to the solution I wouldn't have much gold precipitate out. I also have about 5lbs of fingers and about 20lbs of ram that I could run through the solution to use up more of the cyanide if need be. The first day I started was a very sunny day so the solution had enough UV light. The only time it didn't have light was over night obviously but there was only a hand full of material left in the solution over night which was the ceramic CPUs. By the way I did open the lid from the CPus before putting into solution.

I do have a question tho. The brass and copper items that have had some of the gold precipitate too, what process would you recommend getting that gold off?

 

[Mcnew32(Ag)]

The material that you see was all done according to the type of material. I did not just dump it all in at once. Hence reason for so much extra liquid from washes. Once on type of material was complete or close I would pour off wash material then start new material.

 

[frank-20011]

hello,

one question about the UV-fact.

the producer didn't speak about it and i think that the uv-part of the daylight is mostly, very mostly filtered out by the window glass, above all by the modern combined-window-systems with 2 or 3 (or more) window panes and hoy much of these very, very little UV which passed the window is present in the near of a back wall of a room ant the at the bottom of a plastic pail?

do UV real play such a big main role in the eco goldex process?

and again, why the add NH3 AFTER the leaching process to the eco goldex sollution which is basi enough by itself?

best regards!

 

[Deano]

Look at my post of July 19, the active component of the leach is the ferrocyanide which requires UV to disassociate into the CN- complex.

No UV, no CN-, simple as that.

Not a lot of UV is required but some is on a continuing basis.

I have no idea why you would use a proprietry leach rather than just buying the straight ferrocyanide.

The oxidiser present in the proprietry leach will give you major problems if you try to zinc the gold values from the liquor but will not cause problems for activated carbon adsorption.

If you use straight ferrocyanide as your leachant the only oxidant required is dissolved oxygen from the air, this is via a fine bubble sized bubbler or similar.

Feel free to pay extra for a proprietry product which will give you problems not gotten with straight ferrocyanide.

You still need to use the same conditions of pH 11 no matter which cyanide type leach you use.

Generally a little marketing patter for these types of products makes them seem even better than the basic chemical.


Deano

 

[anachronism]

^^^^^ What Dean said.

I wasn't being my usual blunt self but as Dean has pointed out numerous times, along with others, is that this a straight cyanide leach but wrapped in a more eco friendly wrapper.

So you pay for the base chemical or you buy the same chemical within a bunch of useless stuff for loads more money.

 

[FrugalRefiner]

I believe Deano meant his post of June 19 Eco-goldex.

Potassium ferrocyanide will disassociate in solution to form ferrocyanide complexes, these complexes will decompose to form free cyanide.

Effectively what you are doing is running a cyanide leach where the cyanide concentration is controlled by pH, temperature and UV level.

If you have a cyanide probe you can optimise the conditions to get the maximum free cyanide in solution for leaching.

If you get the conditions wrong you will precipitate out cyanide-metal salts.

If you block out all UV light there is minimal decomposition of the ferrocyanide complex and virtually no free cyanide is formed.

He also discussed it briefly in the sodium thiosulphate And hypochloride leaching thread.

The second option is to use potassium ferrocyanide to generate potassium cyanide.

The only reason you use this method is that the potassium ferrocyanide has virtually no restrictions on transport or storage.

The conditions for use are virtually the same as for sodium cyanide, the only qualifier is that the formation of the cyanide complex is catalysed by UV and thus either sunlight or UV lights at night are required.

Dave

 

[frank-20011]

hello everyone,

i would try eco goldex and so i decide to take all the ingredients written in the msds an mix it by myself (in the EU it isn't easy to buy it) but after all the discussions....and:

"Feel free to pay extra for a proprietry product which will give you problems not gotten with straight ferrocyanide.

You still need to use the same conditions of pH 11 no matter which cyanide type leach you use"

written by Deano i will try straight ferrocyanide but about ferro-leach i can't find anything in the forum search and almost nothing at the web.

in this paper they've wrote about ferrICcyanide gold leaching.

Regards, Frank!

 

[Mcnew32(Ag)]

I have a quick question would I be able to use a stainless steel pot to evaporate some of the water from my eco goldex solution?

Also I was wondering if I would be able to use i high quality stainless steel pot to evaporate some of my stock pot down. If anyone can shed some light on this please let me know.

 

[upcyclist]

I have a quick question would I be able to use a stainless steel pot to evaporate some of the water from my eco goldex solution?

Also I was wondering if I would be able to use i high quality stainless steel pot to evaporate some of my stock pot down. If anyone can shed some light on this please let me know.

I can't comment on the viability of evaporating cyanide & ferrocyanate compounds, but sure, you can evaporate your stockpot liquors down. You'd want to be careful, of course, since it's probably a mixture of various acids. Will it work with stainless? I'm not sure--I'm tempted to think heated acids would eventually attack it, but I'm sure others here have practical knowledge of it. You could also use corningware/pyroceramic cookware to do it--very sturdy, very nonreactive.

Are you looking to evaporate it down to reduce the amount of liquid in your waste stream? Is it worth the time and hazards involved, over just cementing it with copper and moving on to the next stage?