Graphite & Carbon ?

Gold Refining Forum

Help Support Gold Refining Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

kurtak

Well-known member
Joined
Jan 16, 2014
Messages
3,827
Location
John Day Oregon
Does "graphite" pose the same preg robbing problem as "carbon" ?

In other words - as we know carbon - as the result of not reducing carbon to complete ash can/will rob gold from an AR solution --- example - if you don't reduce the epoxy from IC chips to complete ash & thereby have carbon in with your bonding wires when you go to leach it - the carbon will rob at least some (more or less depend on amount of carbon) gold from the AR

Graphite is carbon - but its a different kind (structure) of carbon (as are diamonds) so was just wondering if graphite will rob gold from AR like the carbon from incomplete incineration - or not

If not - I have an experiment I am thinking of trying - on the other hand if it does then there is no sense in trying the experiment

Kurt
 
Kurt not too sure if I'm correct but diamond is a very dense compact form of carbon whereas charcoal is much lighter and much less compact with a huge surface area compared to a diamond of the same size due to its less compact nature, with graphite it's not as compact as diamond but is much more so than charcoal, so following that logic it might have some robbing capacity on its surface but not internally as its structure is reasonably tight.
I stand to be corrected on this if anyone knows for certain one way or the other.
 
It's all about the crystalline structure of the resulting carbon. Graphite, activated carbon, charcoal....all the same element in different crystalline structures.

I know that activated carbon has a very porous structure due to having oxygen content...some of the best made from coconut shells. Charcoal...the same as activated carbon, but generally thought of as a fuel instead of in reference to it's absorptive capacity. Graphite...different crystalline structure all together.
 
Just as an update Kurt. The pic below is of gold recovered from a carbon tower.

Process followed was:

1. Pass the leach liquor up through the activated carbon until loaded.
2. Carbon ashed in furnace until no carbon remained.
3. Ash washed in Nitric/water to remove base metals.
4. Remaining metal processed in AR.
5. Dropped with SMB
6. 1 x HCl wash and 2 x water washes.
7. Dried.
8. Weighed out at 31g from using 2Kg of activated carbon.

Points to note- the AR was done as a recovery drop so no real attention was paid to trying to achieve high purity however as you can see from the picture it certainly came out pretty darned pure....
 

Attachments

  • carbon recovery Jan 2017.jpg
    carbon recovery Jan 2017.jpg
    97.9 KB · Views: 116
What is the advantage of passing leach through the filter?

On edit...through an activated carbon filter
Sent from my iPhone using Tapatalk
 
Carbon is a very strange element.

Depending on how it is arranged with it's neighbouring carbons, it displays a wide range of different behaviours.

'Activated' carbon tends to be just charcoal treated with high-pressure steam which randomly cracks the material at a microscopic level, and also randomly reacts with some of the surface, creating up to 3000m2 of surface area per gramme !

Carbon of all kinds work in the same way, just that 'Activated' does it fast enough to be useful, due to the huge surface area.

Home-made charcoal can be partially 'activated' by just grinding it to as fine a powder as possible, although it will not be as 'active' as shop-bought material.
 
anachronism said:
It recovers the gold from the solution.

Yes, what I'm trying to gather is if you filtered the leach liquor through the carbon filter as part of an experiment to show how much gold can be lost in the carbon matrix, or if filtering through a carbon filter is a routine practice. I don't believe I've read anything on it before.

For those of you that have been doing this for years, is it still as new as it was when you first started? This is FUN!
 
It is a common application, especially in mines, for recovering gold from very weak solutions.

Göran
 
Ok, so this isn't filtering say a liter of leach liquor, more for leaching from a large amount of concentrated ore?
 
He did not said anything about carbon filter. You somehow picked that up and perhaps that confuses you.
You can use liter of leaching solution, pass it through column with activated carbon to strip gold and you can reuse that leach again. And again.
 
Yes, that is what confused me.

I didn't understand the background, as to why, or what would motivate someone to want to pass leach liquor through a carbon filter. Makes lots of sense now though.
 
Carbon is a very strange element.

Depending on how it is arranged with it's neighbouring carbons, it displays a wide range of different behaviours.

'Activated' carbon tends to be just charcoal treated with high-pressure steam which randomly cracks the material at a microscopic level, and also randomly reacts with some of the surface, creating up to 3000m2 of surface area per gramme !

Carbon of all kinds work in the same way, just that 'Activated' does it fast enough to be useful, due to the huge surface area.

Home-made charcoal can be partially 'activated' by just grinding it to as fine a powder as possible, although it will not be as 'active' as shop-bought material.
Can i use coconut activated carbon for water treatment like jacobi cs , or i should use gold activated carbon
Because i can't find gold activated carbon in my area
 
Can i use coconut activated carbon for water treatment like jacobi cs , or i should use gold activated carbon
Because i can't find gold activated carbon in my area
Do not spam the forum with questions in this way.
Ask the question once in an appropriate post, it will be answered, if someone can answer.
The post you are asking in is from 2017.

You have been here long enough to know this, so please stop.
 
If activated carbon is not available in your area, make some. Depending on your scale of needs, you can build accordingly. Watch a couple of youtube videos, it isn't too difficult. The one characteristic you should desire, is it's ability to not break into small pieces. This is because it will get lost in your cyanide solution or material being leached if too small to be retained by the screens in the carbon column. Zadra has done the most complete paper on cyanide leaching from compatible ores, solution chemistry, activated carbon characteristics, stripping solutions, electro winning, or precipitation on Zinc, etc.. Basically the whole ball of wax. I have a copy if someone would like to scan, copy, and post for this web site. I don't have the time. It would almost be as beneficial to the leachers, as Hoke's is to the refiner. Let me know if anyone is interested.
 
Back
Top