Thiosulphate Dropped--Testing for PM?

[Ferrell]

How much gold are you getting out of one steel wool pad? Have some that are coated pretty good havent burned them down just cureous.

Honestly, we don't know yet. We've only done it twice. We've hit the steel wool with a propane torch to burn off all the chemicals, but the wool doesn't really burn very well. We don't have a smelting furnace yet (we hope to purchase one soon) so we're just storing the wool until we can finalize processing it. Right now we're working on setting up an electrowinning system with a titanium plate the way Dr. Poe suggested, as we can't see continuing with the steel wool long term. We have a 110 gal cone-bottom tank we want to use so we can do more than a small, 3 gal batch. Using steel wool for something that large isn't economical and it would be hard to gauge how much we'd need.

I'll let you all know how the experiment goes with the titanium plate after we're done and have tried it.

 

[Dr. Poe]

When your needs are fulfilled, pass this knowledge on to others. Better still, improve on it and also pass it on. When your tax bracket goes up. Remember that I don't charge to help, I do accept gratuities, so does the forum. Noxx has to pay expenses to keep this site going. My personal contact is: [email protected]. Noxx has a site for donations to help keep the forum alive. Dr. Poe

We'll definitely keep that in mind when we start making some 'real' money. We like to pay it forward whenever we can, as well as appropriately thanking those who have helped, or passing along that help to others.

One more quick question....is there a set amount of time the titanium plate should stay in the leach solution? How do we know when it's collected all it will collect?

Before I answer, I advise that you heat treat the titanium prior to it's use. Use a flame and allow the titanium to cement nitrogen from the air to form TiN. This is the way that you get the anode ready. It's not soluble in acids or alkalies, but only in a very hot aqua regia plus hydrofluoric acid (3 acid system). It's ready when it turns bronze yellow. Get a refractometer. Also hang your anode from a scale. watch the weight go up, watch when it stops or at least slows down to almost nothing. Make sense? Dr. Poe

 

[Ferrell]

Before I answer, I advise that you heat treat the titanium prior to it's use. Use a flame and allow the titanium to cement nitrogen from the air to form TiN. This is the way that you get the anode ready. It's not soluble in acids or alkalies, but only in a very hot aqua regia plus hydrofluoric acid (3 acid system). It's ready when it turns bronze yellow. Get a refractometer. Also hang your anode from a scale. watch the weight go up, watch when it stops or at least slows down to almost nothing. Make sense? Dr. Poe

Yes, Allen plans to heat treat it as you suggested, no problem. We'll be using it in the thiosulfate leach (although we'd love to know if it would work in the SSN, as well?).

So you're saying it's ready to take out of the leach when the titanium turns bronze/yellow?

I'm not clear what you're saying about hanging it from a scale to watch it go up, then down. Why? What are we watching for? That's the part that didn't make sense.

In an earlier post you mentioned a rectifier, which Allen was able to pick up. We don't have a refractometer, and have no idea what/how to use one if we did, as we're not familiar with it? Are you suggesting/saying we can't or shouldn't try to extract the gold from the leach with the titanium without one?

Just want to be clear on all points....

 

[rusty]

I'm just another Noob here, I was hoping that Dr. Poe would elaborate on the use of the refractometer and which one would be suitable for metallurgy.

A year ago I took this picture of some IC's I had incinerated, don't have a clue why I decided to take a picture of what looked to be a pile of ash for you could not see the tiny beads with the naked eye. Only after taking the picture, the flash bounced off of the beads giving a blue to violet color almost like an aura.

Since we do not have a reference guide we are left to experimentation, since you are aware of the metals in your leach you already have a leg up.

Use the scale as Dr. Poe suggested, get an inexpensive refractometer, take a sample reading from the beginning to acquaint yourself with the refractometer. When your scale no longer registers a weight gain take another reading from your refractometer.

It is not necessary to have the refractometer, owning one simply makes your job easier to understand and identify when your pregnant leach has become barren of values.

Picture is only to show the effects of light from a camera flash. Your refractometer is more sophisticated.

 

[Dr. Poe]

Rusty's got this one. I can't advise better. Wow! Rusty, look at those blue hues! 75% gold with 25% iron?
Or is that something else? Christmas gold bulb hues. Some times silver will flash that hue. Am I mistaking silver for 18K blue?
Chances are that any silver wouldn't be that pure, so I'm betting 18K blue (gold/iron).

 

[jack_burton]

I'm not clear what you're saying about hanging it from a scale to watch it go up, then down. Why? What are we watching for? That's the part that didn't make sense.

From how I understood this, the weight of the titanium plate will rise as it collects the gold. So suspend it from a scale watch for it to stop getting heavier. I could be wrong, but that's how I read it.

 

[goldaa]

What would you think about igniting the steel wool with a some magniesum ribbon?

 

[Ferrell]

I'm not clear what you're saying about hanging it from a scale to watch it go up, then down. Why? What are we watching for? That's the part that didn't make sense.

From how I understood this, the weight of the titanium plate will rise as it collects the gold. So suspend it from a scale watch for it to stop getting heavier. I could be wrong, but that's how I read it.

Thanks. That's kind of what we ended up deciding, as well.

 

[Wyndham]

This is a golds mine of info,I'm quite amazed.
If I can add a bit of info, there is a company called reactive metals that sell all types of titanium sheets and sizes.
http://www.reactivemetals.com/

I have dealt with them over the years and found them good folks to work with.

I do have one question on using the titanium. If the cathode is titanium what is the anode? I may have missed it in the different post.
Thanks Wyndham

 

[Ferrell]

We did our first test with the steel plate. It turned out that the titanium plate Allen's boss had was too thick and not flexible, so he had to go with two, 4" x 5" flexible steel plates. He didn't have caustic (you said 'hot caustic'....did you mean caustic soda heated up, or something else?) to wash it with, so he hit both sides of both plates with a grinder then a sander to take the surface off.

We mixed 4 gal of thiosulfate leach & 5 lbs of finely ground ore (as we did before), but this time added just over 1/16 of a teaspoon of copper sulfate. You mentioned 1 tsp per 50 gal, so this would be close for 4 gal.

We were able to recover a little over 3 gal of leach from the ore, ran it through a 1 micron filter and got it very clean. The ph was 8.4.

Allen connect a wire to each plate using a DC power supply with knobs to control volts and amps. It puts out 7 amps at its highest, and we had it set at 5 volts.

He suspended the plates with fishing wire from a board across the top of a plastic 12 gal tote and put them into the leach, approx 5" apart. The ph jumped to 8.7 (we checked it about 10 min in) and within about a minute of starting the leach was bubbling and swirling along the edge of the negatively charged plate and the swirls were turning dark. I'll post pictures in order of what happened. First the positive plate started turning totally black from water level down, and the leach got a tinge of green/black, then slowly turned totally green/black. After the positive side of the plate turned black, the top edge just under the fluid started turning orange, like rust. Nothing seemed to be adhering to the negative plate at that time. It ended up having a very thin black film on it that wiped completely off.

We didn't know if we should move the leach around (stir it lightly) to get all of it in contact with the plates, so he did a couple of times. But we noticed the orange line started breaking apart and orange/gold flakes were falling into the leach and floating on top. By the time we finished and removed the plates, there were some very large patches of orange floating on top.

We left the plates in for about an hr then lifted them out. At first it looked like we'd lost all of the strip of orange, but, as you can see from the picture of the plate, after it dried it turned from black to orange on the top 1" or so, and still black below, but with an orange tinge when hit with a flashlight.

As it was drying, little flakes of black were falling off. We caught them on a filter and I also took pics thru the microscope of what those look like close up.

Here are our concerns & questions.

Was the distance apart of the two plates correct? We weren't sure of your instructions on the decimeter distance. Did you mean that it's one decimeter of distance per inch of plate? If that's the case, then with a 4" wide plate, would we be multiplying that by 1 decimeter? If so, we were way off on our distance.

Do the pictures I posted look anything like what it should or did we do it all wrong?

When we pulled the plates out it was still bubbling & swirling around the negative plate. We pulled them due to our concern over so much residue falling off the positive plate into the leach.

 

[Ferrell]

Blast! It loaded my post without letting me do the rest of the pictures. I'm probably doing something wrong, but I'll try again. These will be in order, but it's possible the uploading tool could show them reversed. You want to start viewing from the point the tank/leach is clear.

Looks like I can only do 5 at a time, so I'll put the rest in another post.

 

[Ferrell]

Here's the rest of the pics from my previous post.

Dr. Poe (or anyone who knows) I'd love input on the 10 pics I've posted, as well as the info and questions in my earlier post. We really want to do another batch of leach tomorrow and try again, but want to know what, if anything we're doing wrong....if this looks like it should or if we're way off base.

Thank you for any help anyone can give!!

Miralee and Allen

 

[goldaa]

I would get a teracota flower pot seal the hole in the bottom with silicone then put the anode in the pot hang off the bottom to collect what drops off have done this with a soft steel rod but the titanium works better it plated some gold on to the iron rod. a filter bag works better. I bought a toster oven from the salvation army store and put two pads in it and have run it a 400 degrees for 20 minutes and its breaking down the pads, but will still have to run it with the propane torch. The one I bought has quartz tubes in it. only paid $5.00 dollars for it good deal.

 

[Dr. Poe]

This is a golds mine of info,I'm quite amazed.
If I can add a bit of info, there is a company called reactive metals that sell all types of titanium sheets and sizes.
http://www.reactivemetals.com/

I have dealt with them over the years and found them good folks to work with.

I do have one question on using the titanium. If the cathode is titanium what is the anode? I may have missed it in the different post.
Thanks Wyndham

That's incorrect, plating occurs on the anode with negative charged compounds of gold. The cathode is quite insignificant.
Dr. Poe

 

[Ferrell]

This is a golds mine of info,I'm quite amazed.
If I can add a bit of info, there is a company called reactive metals that sell all types of titanium sheets and sizes.
http://www.reactivemetals.com/

I have dealt with them over the years and found them good folks to work with.

I do have one question on using the titanium. If the cathode is titanium what is the anode? I may have missed it in the different post.
Thanks Wyndham

That's incorrect, plating occurs on the anode with negative charged compounds of gold. The cathode is quite insignificant.
Dr. Poe

Dr. Poe, I'm hoping you'll have time to review the pictures and questions we posted last night in two different posts. We value your advice so much and we're not sure if we're on the right track with the test we ran or not. Thank you!!

 

[Dr. Poe]

Mrs. Ferrell, I'm sorry that I don't seem to make myself clear to you when I post. "Per decimeter" is referring to the area of the anode facing the cathode. Not the distance. When he ground the zinc off, it made the gold hard to flex off. It was no longer smooth. No matter, the amperage was too high as the gold flaked off prematurely. Using the titanium anode (heat treated yellow) and then using a scrapper to remove the gold might have been better than the steel. Getting a thin titanium anode shouldn't be that hard to find. Can anyone here on the forum help Mrs. Ferrel find a vendor of thin titanium anodes?
Until then, turn the amperage down, use a steel plate that's smooth. Remove any galvanization with hot caustic Sodium hydroxide. I've been really busy, I can't visit the forum as often now. Use the e-mail system. My wife will spot it. I won't abandon you and your husband. Anything that I tell you now is just rehashing old posts. You cannot get away from doing your own experiments. For some things, there are no answers until you find them. Not by asking others, but by experimentation.
Send me Google e-mail and I'll send you our phone number. I'm not going to post my phone number on the forum. That would indeed be foolish of me. Dr. Poe

 

[renatomerino]

Dr. Poe:
Very interesting your advice on how to apply gold ore leaching with thiosulphate.
I'm currently leaching silver ores with cyanide but I want to change that also use thiosulfate for gold.
I can report the concentration of thiosulfate solution used in tests please?.

 

[Dr. Poe]

Dr. Poe:
Very interesting your advice on how to apply gold ore leaching with thiosulphate.
I'm currently leaching silver ores with cyanide but I want to change that also use thiosulfate for gold.
I can report the concentration of thiosulfate solution used in tests please?.

As a rule of thumb (general applications) the weight of sodium (ammonium) thiosulfate is twice that of cyanide.
Have you been adding a little lead nitrate to help your cyanidization recovery?
Do you know the amount of copper found in your ore?
Please forgive my late response as I had caught a 24 hour virus and was too sick to think. Dr. Poe

 

[goldsilverpro]

This is a golds mine of info,I'm quite amazed.
If I can add a bit of info, there is a company called reactive metals that sell all types of titanium sheets and sizes.
http://www.reactivemetals.com/

I have dealt with them over the years and found them good folks to work with.

I do have one question on using the titanium. If the cathode is titanium what is the anode? I may have missed it in the different post.
Thanks Wyndham

That's incorrect, plating occurs on the anode with negative charged compounds of gold. The cathode is quite insignificant.
Dr. Poe

That's strange, Poe. In all my years in the plating industry, I've never seen any metal deposit on the anode, as metal. It just doesn't happen. In most all gold plating baths, the gold is in the solution as a negative complex cyanide ion and the plating always occurs on the cathode. When plating silver from thiosulfate fixer solutions, in which the silver is in the solution as a negative complex ion, the silver, as metal, always deposits on the cathode. In that system, a rotating cathode is usually used to forcefully replenish the negative ions, which are repelled by the negative cathode, at the cathode surface (the cathode film).

 

[butcher]

I also have been perplexed on this, and have been watching the discussion, not knowing if I am missing something or if there is some difference in these solutions from the acidic side of electrolysis, which I am more familiar with.

Usually when a metal is in solution with an acid copper and sulfuric for example (copper sulfate (the copper ions being positive plate out to the cathode), (the sulfate being negative move to the anode).

Metal Cation Cu+ migrates to cathode
(Acid) Anions SO4- migrate to anode

This works with all solutions with electrolysis the compound splits.

I have never heard of metal plating to the anode, usually (unless the anode is inert) the anode dissolves into solution (with assistance of freed Anion), and the metal in solution plates out or reduces to metal powders at the cathode releasing the Anion.



I was wondering if this gold thiosulfate complex was something abnormal from what I am used to (plating to anode??), or if they were calling electrodes backwards from what I would call them.

I was thinking if I waited and kept reading the answer would surface to my question, but since GSP asked this question I also would like to understand this better.