Eco-goldex CYANIDE Leach

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I used it on some gold filled jewelry items and although it took about 5 days it seemed to work quite well. Patnor, thanks so much for all your guidance with this method of gold recovery. Did you say that I should incinerate my activated carbon prior to using it to absorb the gold particles?
 
No, I did not. I used it straight as I got it. After it is loaded with gold it need to be ashed. Do not use torch like I did. Torch will blow away fine ash along with gold which happened to me :oops: .
Use what Deano suggested. Some kind of furnace.
 
patnor1011 said:
No, I did not. I used it straight as I got it. After it is loaded with gold it need to be ashed. Do not use torch like I did. Torch will blow away fine ash along with gold which happened to me :oops: .
Use what Deano suggested. Some kind of furnace.
hi , I searched eco goldex web site and they sell a furnace for $880.00. I cant afford that right at the moment. hope everyone has luck with this process . waiting for good results here , ed.
 
I've been trying to order some but the site was calculating the shipping at like $140 for a couple kg order to the next province..
Now i see the site is trowing errors on the zinc and carbon pages so i am a little cautious.
 
ettran said:
patnor1011 said:
No, I did not. I used it straight as I got it. After it is loaded with gold it need to be ashed. Do not use torch like I did. Torch will blow away fine ash along with gold which happened to me :oops: .
Use what Deano suggested. Some kind of furnace.
hi , I searched eco goldex web site and they sell a furnace for $880.00. I cant afford that right at the moment. hope everyone has luck with this process . waiting for good results here , ed.
hi again , I bought some eco-goldex - E and waiting for it.tried the first sample and it strips the gold after a week but turns blue fluid and leaves a mixed white and black percipatant on the bottom . hope goldex -E solves my problem.ed.
 
If it took a week and dissolved copper on process (blue) then there was something wrong. It should and in my case did stripped gold literally within minutes. You need to apply correct ph and do use air bubbler. I do use air bubbler so solution is moving constantly around material. I stripped all kind of material as you can see in pictures here and none of them took longer than 15-20 minutes. With exception of my first try when I did not got it right with ph and after few days when not much was going on I overdid it with lye and ended up with copper on fingers dissolved when I left it there overnight. It is crucial to get ph within reccommended range but if you make it there you will be flying.
 
Kilroy2k1 said:
I've been trying to order some but the site was calculating the shipping at like $140 for a couple kg order to the next province..
Now i see the site is trowing errors on the zinc and carbon pages so i am a little cautious.

Send him email or just call him but I cant see the need of having kilograms of it unless you do plan to use it to leach ore. As far as I know you can strip whole lot of material with just few grams and then adsorb gold with carbon and reuse solution again.
 
patnor1011 said:
Send him email or just call him but I cant see the need of having kilograms of it unless you do plan to use it to leach ore. As far as I know you can strip whole lot of material with just few grams and then adsorb gold with carbon and reuse solution again.

Hi Patnor, are you still thinking about buying stuff together? I'm trying to order 2kgs to Czech republic but it says $111 (I've used code) including shipping, which cost $60. It is too much in my opinion. And it's still necessary to pay VAT and duty when package is comming to EU.

BTW: zinc metal powder here cost about 12 EUR / kg (including shipping). Is it expensive?
 
Thanks for the reply guys.
It would seem the gent was just busy and low on stock of carbon and zinc. he did get back to me and we completed the transaction and its already shipped to me.
I'm still curious if anyone has done a successful recovery from the solution.
 
I asked John while back about it and he was in discussion with some companies in EU to set some sort of eu re-seller. Group buy will only make sense if purchased amount will be high and sent by sea to save on shipping costs - couple hundred kilograms or ton of the stuff which I do not have capacity to store. As far as I remember it was something like 2000$/mt but I am not self employed or company to even think about that kind of amount of reagent.
 
patnor1011 said:
I asked John while back about it and he was in discussion with some companies in EU to set some sort of eu re-seller. Group buy will only make sense if purchased amount will be high and sent by sea to save on shipping costs - couple hundred kilograms or ton of the stuff which I do not have capacity to store. As far as I remember it was something like 2000$/mt but I am not self employed or company to even think about that kind of amount of reagent.
hi,how much zink powder should you use per liter of solution ? ed.
 
ettran said:
patnor1011 said:
I asked John while back about it and he was in discussion with some companies in EU to set some sort of eu re-seller. Group buy will only make sense if purchased amount will be high and sent by sea to save on shipping costs - couple hundred kilograms or ton of the stuff which I do not have capacity to store. As far as I remember it was something like 2000$/mt but I am not self employed or company to even think about that kind of amount of reagent.
hi,how much zink powder should you use per liter of solution ? ed.

If I only know. This thread is work in progress, I do not have any step by step solution or exact recipes. I thought that if some people will want to try it it may be cool to share experiences. I shared what I did so far there is not much more to add for now. I do not consider using zinc in future, I am going to focus on gold recovery with carbon.
 
How to use zinc powder/stripes to precipitate gold out of the pregnant solution

Step 1: Drop gold out of the pregnant solution
•Separate pregnant solution and residual materials by filtering; storing pregnant solution in a container;
•With constant stirring (for zinc powder), adding zinc powder into pregnant solution (use the ratio of 1 g Au : 2-4 g zinc powder);
•The gold will drop out and appear as a brownish powder.
•To insure all the gold drop out, add a slight excess of zinc, which is of a gray color. Add the zinc in increments, allow it to work for a couple of minutes, and observe the color. When the observed powder is of a uniform gray color, all the gold should be out.
•Allow the powder to settle overnight, Either siphon or dip off most of the solution without disturbing the settled solids.
•For zinc strips precipitation, just sock curl zinc strips into the pregnant solution, let the chemical reaction does its work for 6-10 hours.
•Filter (coffee filter paper can do the job) the solids and retian all the solids from the filter paper and put them into a plastic bucket. Keep the filter paper(s) for future incineration.

Step 2: purify gold with acid washing

•Add proper amount of water to the solids and stir a bit to break up the solids and create a slurry;
•UNDER A FUME HOOD!, add a small amount of concentrated HNO3 or H2SO4 acid. You should see an immediate reaction. When the reaction subsides, give it a stir and add a little more acid. Repeat until an addition of acid produces no reaction; this step is to remove base metallic elements such as Cu, Fe… that might be dissolved during stripping process. And extra Zn strips remain. Base metal sulfides(i.e. CuSO4, FeSO4, ZnSO4) are soluble in water, while Au can’t be dissolved by H2SO4 or HNO3. these base metals (junks) will be separated from Au through filtration.
•Filter the acid solution and transfer the solids to a beaker, cover with water, and heat to a little below boiling. Add some acid and heat for about 15 minutes to make sure all soluble base metal sulfites are dissolved.
•Filter the solids and rinse several times with hot water. Remove the solids from the paper and slowly dry.
•At this point, you should have 99+% gold powder(usually dark color!). To purify it further, you can use the standard aqua regia method.

This is from eco-goldex E series instruction PDF sheet.

Dwayne
 
To add to the thread be aware that dropping gold out of cyanide solutions using zinc can be difficult to almost impossible depending on what else is in the original solution, the only way to be totally sure you have all the gold out is with assays so assay your solution before attempting to drop it.
 
Thanks Nick

You do also need to be aware that using activated carbon with this particular product can cause its own set of problems too. UV breaks the ferro-cyanide bond hence the free cyanide for the leach in this product. The bond is remade when the product is put back in the dark. An activated carbon tower takes ALL the metals onto the carbon including the iron.

The reason zinc is recommended is that the zinc precipitation leaves the iron in solution. Yes you can use activated carbon but you do need to be aware of, and prepare for the iron that you are likely to get in your ash. Not a major issue if you're prepared for it of course.

You could actually short circuit the whole process by buying ferrocyanide and just using that with an oxidant under UV. Same old same old but the restrictions on buying ferrocyanide are nowhere near those for buying a cyanide metal salt such as Potassium or Sodium Cyanide. In fact I don't think it's even on a restricted list although I'm open to be corrected. That's the whole crux of this branded product in a nutshell. You can sell it and ship it with no restrictions.

It needs education though because in essence it's the same process as a full blown KCN or NaCN leach. Call it a workaround if you will.

Credit to Deano for the additional chemistry.

Edit for accurate description.
 
Well if the carbon strips all the metals including the iron surely your left with a cyanide solution as the waste solution as the carbon will leave most of the cyanide alone so it's back to the same old problem who wants to work with cyanide...
Or is my physics/chemistry wrong here.
 
nickvc said:
Well if the carbon strips all the metals including the iron surely your left with a cyanide solution as the waste solution as the carbon will leave most of the cyanide alone so it's back to the same old problem who wants to work with cyanide...
Or is my physics/chemistry wrong here.

You've pretty much hit the nail on the head old friend. :D
 

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