Leach process for large quantity of black sands

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Did they expose it to sufficient UV in the lab tests. According to what I found when researching eco-goldex, it is the ferricyanide and/or ferrocyanide that does the work, but it requires UV light to break the iron bond and free the CN-.

Dave
 
Did they expose it to sufficient UV in the lab tests. According to what I found when researching eco-goldex, it is the ferricyanide and/or ferrocyanide that does the work, but it requires UV light to break the iron bond and free the CN-.

Dave
I do not know the details exactly, but as far as i know, it also work in glass vessels on regular daylight, where passage of UV isnt very good. They used it according to the manual and measured the CN content along the way. But they didn't found any.
 
My point is how we determine CN- anion in the powder or solution via XRF. We all know very well that anything below Mg is hard to measure by XRF due to small atomic radius. C and N are way off from the magnesium, much lighter. I am just intrigued how they measured it. Powder diffraction ? Does CN- have specific pattern on powder XRF reading ?

Also, if it is encapsuled CN- with organic additives, how you distinguish carbon from that encapsulation from CN- carbon.

Guys from one mining company tested the EcoGoldex in certified lab by certified methods for CN- detection, but they found no free CN- in the solution. That is why I am intrigued about Ultrax method to prove/disprove free cyanide in EG.
Sorry for the confusion, I'm simplifying a bit for the forum :)
It is quite obvious that we use a laboratory and complex physicochemical multi-stage method for determining the composition. XRF is used to determine the type of complexing agent, not CN ligands (and by the way with XRF we can start with Na, not Mg :) Further we use other methods - sorry, they are under NDA.
I can only say that in the EcoGoldex solution works free CN groups, just like in ordinary cyanide :)
In general, we have had more problems with recycling and decomposition of waste after EcoGoldex than after ordinary cyanide :)
 
Sorry for the confusion, I'm simplifying a bit for the forum :)
It is quite obvious that we use a laboratory and complex physicochemical multi-stage method for determining the composition. XRF is used to determine the type of complexing agent, not CN ligands (and by the way with XRF we can start with Na, not Mg :) Further we use other methods - sorry, they are under NDA.
I can only say that in the EcoGoldex solution works free CN groups, just like in ordinary cyanide :)
In general, we have had more problems with recycling and decomposition of waste after EcoGoldex than after ordinary cyanide :)
Thanks for explanation :)
 
Keep it simple and do what nature does, is usually the best way to go. 2 words...ball mill. I usually mill about 3 tons a week of black sands and sulfides to 400 mesh. That will release 95% of gold that is locked up and run it back over the table. 5 tons a day, is going to require a larger ball mill than I have but it will be the same process, no chemicals needed.

run the ore, crush, and extract. what's not collectible, put in ball mill, grind to 400 mesh, extract again on table. regrind and crush as needed to ensure all (or most) of gold is extracted...wash, rinse, repeat... It's the same process mother nature uses and by far the most cost effective.

Simple effective DIY ball mill idea to process 5 tons or more a day..... cement mixer, steel balls and water. (but it can be done dry, wet is faster and more effective and easier on the equipment) You want to use roughly 1/2 the weight in steel balls as what you're grinding. 1000 lbs black sands, 500 lbs steel balls...2000 lbs black sands, 1000 lbs steel balls, etc. I use a DIY ball mill from a small cement mixer and 200 lbs steel balls, processes about 1000 lbs a day and about 3 tons per week.

keep it simple.
 
Keep it simple and do what nature does, is usually the best way to go. 2 words...ball mill. I usually mill about 3 tons a week of black sands and sulfides to 400 mesh. That will release 95% of gold that is locked up and run it back over the table. 5 tons a day, is going to require a larger ball mill than I have but it will be the same process, no chemicals needed.

run the ore, crush, and extract. what's not collectible, put in ball mill, grind to 400 mesh, extract again on table. regrind and crush as needed to ensure all (or most) of gold is extracted...wash, rinse, repeat... It's the same process mother nature uses and by far the most cost effective.

Simple effective DIY ball mill idea to process 5 tons or more a day..... cement mixer, steel balls and water. (but it can be done dry, wet is faster and more effective and easier on the equipment) You want to use roughly 1/2 the weight in steel balls as what you're grinding. 1000 lbs black sands, 500 lbs steel balls...2000 lbs black sands, 1000 lbs steel balls, etc. I use a DIY ball mill from a small cement mixer and 200 lbs steel balls, processes about 1000 lbs a day and about 3 tons per week.

keep it simple.
Screenshot from 2022-09-10 13-04-10.png
 

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Not sure what that's supposed to say. -50 mesh is easily collected on the table. Most of the gold I was referring to is going to be -150 or still locked in black sands and/or sulfides. Grinding in the ball mill extracts down to 400 mesh, easily retrieving the 1 oz+/ton in the original post. It's specifically for not using chemicals because processing 5 tons/day will run into millions $$$ IF anyone can get a permit for cyanide leaching.
 
Do you use portable XRF with start detecting from Mg? Just curious :)
I am not sure if it can do Na, but it shows Mg, and Geochem shoot quite OK the bulk of constituents of matrix... OLYMPUS Vanta :) better advertised than really functioning :D sharp step from older Elvax or NITON devices tho
 
Keep it simple and do what nature does, is usually the best way to go. 2 words...ball mill. I usually mill about 3 tons a week of black sands and sulfides to 400 mesh. That will release 95% of gold that is locked up and run it back over the table. 5 tons a day, is going to require a larger ball mill than I have but it will be the same process, no chemicals needed.

run the ore, crush, and extract. what's not collectible, put in ball mill, grind to 400 mesh, extract again on table. regrind and crush as needed to ensure all (or most) of gold is extracted...wash, rinse, repeat... It's the same process mother nature uses and by far the most cost effective.

Simple effective DIY ball mill idea to process 5 tons or more a day..... cement mixer, steel balls and water. (but it can be done dry, wet is faster and more effective and easier on the equipment) You want to use roughly 1/2 the weight in steel balls as what you're grinding. 1000 lbs black sands, 500 lbs steel balls...2000 lbs black sands, 1000 lbs steel balls, etc. I use a DIY ball mill from a small cement mixer and 200 lbs steel balls, processes about 1000 lbs a day and about 3 tons per week.

keep it simple.
Gold is never in the crystal lattice of magnetite - usually, it is hydrothermal co-precipitation (in the geological sense) in which gold particles are physically overgrown with hydroxides and iron oxides, binding very firmly precisely mechanically (!).
No amount of crushing by pressure (let aside mill with steel balls) will help free these gold particles from hydroxide shells. Moreover, oxides are often covered with a dense layer of organic bitumens - which make magnetite generally insensitive to any(!) acids or mechanical actions. Even roasting at 700-800C does not help 100%. So practically, such magnetite totally does not dissolve in anything without an autoclave and very aggressive oxygen oxidation. We have such type of ore (ferroaurates), and we were able to wash off bitumens coating from ferroaurates only with xylene - and then only partially.
Therefore, if you have ferroaurate (gold in magnetite), your only way is chemical leaching after opening the magnetite.
Opening the magnetite is a more complex problem than opening the sulfides. You can find the best solution on your specific ore in practice.
 
Gold is never in the crystal lattice of magnetite - usually, it is hydrothermal co-precipitation (in the geological sense) in which gold particles are physically overgrown with hydroxides and iron oxides, binding very firmly precisely mechanically (!).
No amount of crushing by pressure (let aside mill with steel balls) will help free these gold particles from hydroxide shells. Moreover, oxides are often covered with a dense layer of organic bitumens - which make magnetite generally insensitive to any(!) acids or mechanical actions. Even roasting at 700-800C does not help 100%. So practically, such magnetite totally does not dissolve in anything without an autoclave and very aggressive oxygen oxidation. We have such type of ore (ferroaurates), and we were able to wash off bitumens coating from ferroaurates only with xylene - and then only partially.
Therefore, if you have ferroaurate (gold in magnetite), your only way is chemical leaching after opening the magnetite.
Opening the magnetite is a more complex problem than opening the sulfides. You can find the best solution on your specific ore in practice.
interesting...
 
Did they expose it to sufficient UV in the lab tests. According to what I found when researching eco-goldex, it is the ferricyanide and/or ferrocyanide that does the work, but it requires UV light to break the iron bond and free the CN-.

Dave


As far as I am aware, there is no Ferri/Ferro cyanide in the LV/Eco-Goldex/JinChan leaches. They are essentially all the same with slight changes in the embodiments.

They use Sodium Cyanate, some Thio, oxidisers and bases.. here is the patent number CN107287439A
 

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Gold is never in the crystal lattice of magnetite - usually, it is hydrothermal co-precipitation (in the geological sense) in which gold particles are physically overgrown with hydroxides and iron oxides, binding very firmly precisely mechanically (!).
No amount of crushing by pressure (let aside mill with steel balls) will help free these gold particles from hydroxide shells. Moreover, oxides are often covered with a dense layer of organic bitumens - which make magnetite generally insensitive to any(!) acids or mechanical actions. Even roasting at 700-800C does not help 100%. So practically, such magnetite totally does not dissolve in anything without an autoclave and very aggressive oxygen oxidation. We have such type of ore (ferroaurates), and we were able to wash off bitumens coating from ferroaurates only with xylene - and then only partially.
Therefore, if you have ferroaurate (gold in magnetite), your only way is chemical leaching after opening the magnetite.
Opening the magnetite is a more complex problem than opening the sulfides. You can find the best solution on your specific ore in practice.
Method for the assay and recovery of precious metals

Patent, US5238485A.

Abstract​


Complex ores of the precious metals which also contain iron spinels and similar compounds are assayed and their precious metals content is extracted by subjecting the ores or concentrates thereof together with an iron-embrittling agent to a pyrometallurgical process which reduces at least a major portion of the iron compounds to liquid metallic iron.

The liquid iron serves as a collector metal for the precious metals and, after cooling, the iron is brittle and easily comminuted and can be separated from the precious metals through use of either an electrolytic process or a selective chemical dissolution of the iron and other base metals leaving the precious metals available for analysis and recovery.





So what is the 'embrittling agent' ??? Any ideas
 
My point is how we determine CN- anion in the powder or solution via XRF. We all know very well that anything below Mg is hard to measure by XRF due to small atomic radius. C and N are way off from the magnesium, much lighter. I am just intrigued how they measured it. Powder diffraction ? Does CN- have specific pattern on powder XRF reading ?

Also, if it is encapsuled CN- with organic additives, how you distinguish carbon from that encapsulation from CN- carbon.

Guys from one mining company tested the EcoGoldex in certified lab by certified methods for CN- detection, but they found no free CN- in the solution. That is why I am intrigued about Ultrax method to prove/disprove free cyanide in EG.

Regarding the residual CN in Eco-Goldex, in a test in Africa, with CN against JGD (Jin Chan Gold Dressing agent - same as Eco-Goldex), they did find residual Free CN. Please see attached table. The optimal concentration they found for CN was around 250ppm and for JGD was 400ppm.
 

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So what is the 'embrittling agent' ??? Any ideas
Dissolve PGM in molten iron as a collector? Did the author of US5238485A even see the state diagram of the Au-Fe system? This is obvious economic madness :) Author filed a patent for the sake of the patent itself :)

P. S. Yes it is possible to collect gold in matte from sulfide ore (it's old multi-stage Hungarian medieval technology) but molten iron is NOT a matte.
 
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So what is the 'embrittling agent' ??? Any ideas
Both steel and cast iron are made from the same mineral, cast iron comes in many grades some of which are easier the break than others.

It's only a guess but I'm thinking you want to turn the iron into something very brittle.

To make steel they inject oxygen into the molten metal.

In the video Primitive Technology he used carbon in his furnace which in turn consumed the oxygen from the oxides, leaving him with globules of metal.

Would have been interesting to see an assay of his metal then we would know which other elements is had picked up from the source material.

Iron will alloy with a lot of other metals.

If you focus on black sand and not the precious metals your after your research will stall.

Metals smelting-collection method for recycling of platinum group metals from waste catalysts: A mini review.

How to Smelt Iron: The 6 Steps to Iron Smelting | The Crucible.

During medevil times the metal used to make a sword was of such poor quality the word would often break during battle.
 
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Dissolve PGM in molten iron as a collector? Did the author of US5238485A even see the state diagram of the Au-Fe system? This is obvious economic madness :) Author filed a patent for the sake of the patent itself :)

P. S. Yes it is possible to collect gold in matte from sulfide ore (it's old multi-stage Hungarian medieval technology) but molten iron is NOT a matte.
Agree
 
If you dissolve some of the powder in water you measure the cyanide level in the water using a cyanide probe, usually on a handheld meter.
This is technology which has been around for well over a decade and is widely used in the gold mining industry.
Deano
 

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