Further to some posts i made a few months ago when i began researching leaching technology that is easily/legally available to non-accredited lab owners in Canada ...
One of my mining partners and i obtained some of the Chinese leaching agent ... and a couple months ago, we've began experimenting with the leaching agent on both computer parts and placer gold.
After about a week of experimenting with the leaching agent, we found that we got pretty good/fast leaching results by adding excessive oxygen/air injected into the leach liquid ... with excessive air being injected into the leaching liquid, the gold coatings on the computer parts were stripped in mere minutes, around 5 minutes or less ... while the much thicker placer gold pieces (200 mesh to 20 mesh pieces) we found it took anywhere from a couple/few hours to over-night to completely liquefy the placer gold pieces, depending on their individual sizes.
So now that we have the leaching process dialed in ... we are now experimenting to get the electro-winning process dialed in.
Our 1st electro-winning experiment was a basically bust ... i "wasn't" present when my partner tried the first electro-winning test ... but the visual results from the first test didn't reveal any discernible recovered visible Gold.
For our 2nd electro-winning test .... i "was" present ... and we did get some successful visible Gold recovery ... but our recovery results were only a small fraction of the Gold that was dissolved into the solution ... so, what we are trying to figure out now is; what are we doing wrong that is leading to a very low Gold recovery rate.
Here's how our 2nd electro-winning process went ...
- (1.) ... The Gold ..... we dissolved 3 grams of placer Gold into solution ... multiple previous assays and historical records show the Gold from this drainage averages around 86 percent purity, with the balance being primarily a Silver impurity.
- (2.) ... The Temperature & Stirring ..... using the Slendor base (see PICT 1 - SLENDOR) we were able to heat the pregnant solution to aprox. 41 degrees C ... and we were able to stir the solution while the anode/cathode plates are in the solution ... we had the stir settings on a fairly gentle setting ... you can see the small vortex from the stirrer in between the anode & cathode in the PICT 2 - VORTEX ...
- (3.) ... The Battery Power - 1 ..... at first, we used a 6 volt dc battery ... and connected the copper anode/cathode plates ... lots of bubbles formed off the cathode in the pregnant solution, we pulled the cathode after aprox. 30 minutes for a visual inspection, and basically no noticeable gold formed on the cathode.
- (4.) ... The Battery Power - 2 ..... we then switched out the 6 volt dc battery for a small little 1.5 volt dc battery ... we noticed much fewer bubbles forming off the cathode in the pregnant solution ... we pulled the cathode after being in solution for aprox. 20 to 30 minutes for visual inspection ... and we a noticed a discernible amount of nice bright yellow gold deposited onto the cathode ... see PICT 3 - GOLD RECOVERY ...
- (5.) ... Continuing On ..... we then put the cathode back into the solution, connected to the 1.5 volt dc battery for another 20 to 30 minutes ... we noticed that the amount of bubbling coming off the cathode diminished quite quickly - eventually producing almost no bubbles ... it appeared that very little new Gold was being deposited on the cathode ... after aprox 20 to 30 minutes, we pulled the cathode for visual inspection, and it appeared that very little additional Gold was being deposited onto the cathode ... we also noticed that the color or coating on the previously bright yellow gold turned to a much darker shade ... see PICT 4 - DULL COATING ...
- (6.) ... Stopped Testing ..... after the bright yellow Gold turned dark, we decided to stop the experiment that afternoon, as it was also getting late in the afternoon.
Now we are trying to figure out the following .....
- (A.) ..... why were we only able to recover only a very small amount of the Gold in solution? ... ie; we only recovered aprox. a 1/4 gram Gold at most ... but we dissolved a total of 3 grams of placer gold in solution ... so with an aprox. 86% Gold purity, there should be aprox. 2.58 grams of Gold in the pregnant solution ... which means we only achieved aprox. a 10% recovery rate at best.
- (B.) ..... why did the Gold recovered on the cathode turn from a nice bright yellow color to eventually a much duller/darker shade/coating?
- (C.) ..... what are we doing wrong? ... or what should we be doing differently? ... for example, in hindsight, we could have turned up the stirrer settings quite a bit, which would have dispersed the ions in the pregnant solution much more aggressively ..... should we be using a different battery voltage? - ie; 2.0 or 2.5 volts?.
Any insights greatly appreciated
One of my mining partners and i obtained some of the Chinese leaching agent ... and a couple months ago, we've began experimenting with the leaching agent on both computer parts and placer gold.
After about a week of experimenting with the leaching agent, we found that we got pretty good/fast leaching results by adding excessive oxygen/air injected into the leach liquid ... with excessive air being injected into the leaching liquid, the gold coatings on the computer parts were stripped in mere minutes, around 5 minutes or less ... while the much thicker placer gold pieces (200 mesh to 20 mesh pieces) we found it took anywhere from a couple/few hours to over-night to completely liquefy the placer gold pieces, depending on their individual sizes.
So now that we have the leaching process dialed in ... we are now experimenting to get the electro-winning process dialed in.
Our 1st electro-winning experiment was a basically bust ... i "wasn't" present when my partner tried the first electro-winning test ... but the visual results from the first test didn't reveal any discernible recovered visible Gold.
For our 2nd electro-winning test .... i "was" present ... and we did get some successful visible Gold recovery ... but our recovery results were only a small fraction of the Gold that was dissolved into the solution ... so, what we are trying to figure out now is; what are we doing wrong that is leading to a very low Gold recovery rate.
Here's how our 2nd electro-winning process went ...
- (1.) ... The Gold ..... we dissolved 3 grams of placer Gold into solution ... multiple previous assays and historical records show the Gold from this drainage averages around 86 percent purity, with the balance being primarily a Silver impurity.
- (2.) ... The Temperature & Stirring ..... using the Slendor base (see PICT 1 - SLENDOR) we were able to heat the pregnant solution to aprox. 41 degrees C ... and we were able to stir the solution while the anode/cathode plates are in the solution ... we had the stir settings on a fairly gentle setting ... you can see the small vortex from the stirrer in between the anode & cathode in the PICT 2 - VORTEX ...
- (3.) ... The Battery Power - 1 ..... at first, we used a 6 volt dc battery ... and connected the copper anode/cathode plates ... lots of bubbles formed off the cathode in the pregnant solution, we pulled the cathode after aprox. 30 minutes for a visual inspection, and basically no noticeable gold formed on the cathode.
- (4.) ... The Battery Power - 2 ..... we then switched out the 6 volt dc battery for a small little 1.5 volt dc battery ... we noticed much fewer bubbles forming off the cathode in the pregnant solution ... we pulled the cathode after being in solution for aprox. 20 to 30 minutes for visual inspection ... and we a noticed a discernible amount of nice bright yellow gold deposited onto the cathode ... see PICT 3 - GOLD RECOVERY ...
- (5.) ... Continuing On ..... we then put the cathode back into the solution, connected to the 1.5 volt dc battery for another 20 to 30 minutes ... we noticed that the amount of bubbling coming off the cathode diminished quite quickly - eventually producing almost no bubbles ... it appeared that very little new Gold was being deposited on the cathode ... after aprox 20 to 30 minutes, we pulled the cathode for visual inspection, and it appeared that very little additional Gold was being deposited onto the cathode ... we also noticed that the color or coating on the previously bright yellow gold turned to a much darker shade ... see PICT 4 - DULL COATING ...
- (6.) ... Stopped Testing ..... after the bright yellow Gold turned dark, we decided to stop the experiment that afternoon, as it was also getting late in the afternoon.
Now we are trying to figure out the following .....
- (A.) ..... why were we only able to recover only a very small amount of the Gold in solution? ... ie; we only recovered aprox. a 1/4 gram Gold at most ... but we dissolved a total of 3 grams of placer gold in solution ... so with an aprox. 86% Gold purity, there should be aprox. 2.58 grams of Gold in the pregnant solution ... which means we only achieved aprox. a 10% recovery rate at best.
- (B.) ..... why did the Gold recovered on the cathode turn from a nice bright yellow color to eventually a much duller/darker shade/coating?
- (C.) ..... what are we doing wrong? ... or what should we be doing differently? ... for example, in hindsight, we could have turned up the stirrer settings quite a bit, which would have dispersed the ions in the pregnant solution much more aggressively ..... should we be using a different battery voltage? - ie; 2.0 or 2.5 volts?.
Any insights greatly appreciated
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