I tried Potassium Peroxymonosulfate.....help!!!!

[fixinator]

Here is my orriginal post on another thread:




Joined: 10 Apr 2007
Posts: 32
Location: Southwest Michigan

PostPosted: Thu Jan 08, 2009 8:37 pm Post subject: Reply with quote Edit/Delete this post
Shocked Embarassed I tried something similar to this. It seemed all was well until I tried to precipitate the gold. Now I have a smelly mess. I used the potassium monopersulfate to regenerate the acid peroxide solution.

It was working so well I just kept stripping and dissolving parts. I even threw in a couple pellets of pool chlorine. It dissolved all the metals. There was no black powder left on the bottom of the pail.

Now the dilemma. I had a busy summer and didn't have much time to work the lab in my shed. Now it's cold. I brought this bucket and a couple others in to the garage to work. After testing with SnCl I diluted this solution approx 1.5x. I then started adding smb. I could see the gold precip in a thick cloud. I walked away for awhile and when I came back there was no gold powder to be seen. Twisted Evil I added more smb, then more. I read on this forum that excess oxidizers can be wiped out with smb. I added alot (about 3.5 pounds altogether) at regular intervals. I added smb in solution, powder and chunk. each time it precipitated gold heavily. Later it was gone.

The solution still has a rapid stain when tested.

I tried pushing it out with copper then iron. NO LUCK!!

After reading that patent I think the problem is that it made a water soluble form of gold chloride. Or gold halide perhaps. Now I don't have any sodium borohydride or the facilities to follow this part of the patent. I hesitate to boil because I have already seen values condensing on the bucket lid.

Incidentally The addition of the iron caused strong odor of hydrogen sulfide in the sample I added it to.

This stuff works too well!!! It also takes a different method to precipitate.

If any of you knowledgeable people have an idea how to recover my values......I would gladly buy you dinner!!!



The products used were HCl, H2O2 to get it started, then non-chlorine pool shock (42.8% Potassium Peroxymonosulfate) to regenerate, I admit using this to excess. I also added some clorox, about a pint over a two month period and a couple stabilized chlorine tablets like you would use in a pool. This mix was digesting metals very well. Now I can't get them back.

I tried to keep solder and other nasty base metals out. Of course there is going to be some copper and other things that are unavoidable. Most of what was dissolved was fingers, a few processors and some other pieces that had gold plating. I didn't keep a record of how much I put in the bucket but it was alot. This was my experiment that got carried away.


Last night I culled out 150 ml and added 1 level tsp sodium hydroxide to it. I then added another 40 ml water to wash it all down into solution. The first thiing that happened is the formation of yellow sponge at the top and bottom of the solution. It weems that the excess sodium hydroxide settled on the bottom below this sponge. Now about 18 hours later the top sponge has dropped and the solution still tests positive with stanous.

Apparently my photos are too big, they would not attach. I'll re size and try again.

 

[OMG]

You must have a LOT of excess acid in there if it keeps redissolving the gold. Maybe if you think it would be worth it, see if BDG would be useful in extracting the gold. Otherwise if I were you, I'd use something to raise the pH then precipitate the gold.

 

[fixinator]

This problem may be resolving. One of the samples I separated I added a small amount of sludge from my stock pot. It took a few days but now there is almost no SO2 odor from this sample. Also this solution now tests negative. I realize that I will have to refine the sediment now. Of course with much less oxidizer, hehehe. A second sample also tests negative and had a beautiful light brown sediment that can be seen through 7 inch deep solution in the bucket. This one still is strong on the SO2. The main 2 buckets are still strongly positive and are now showing sediment on the bottom of the buckets. Perhaps in a few days these too will finish.

The last sample, a small bit in a graduated cylinder shows much color. In this I added a small amount of Sodium Hydroxide. This still tests positive although the reaction in the test filter is slow and weaker than the rest.

I'll once again try to attach photos.

 

[fixinator]

OK folks......progress is being made. By raising the ph, icing and starting the precipitation with a piece of galvanized steel (only for about an hour) the gold and probably alot of other stuff as well is dropping very slowly. It takes about 2 to 3 days for the solution to clear.

I also found alot of info here:

http://www.dupont.com/oxone/techinfo/index.html#incompatible

This is very similar to caro's acid. I mixed it with HCl and stabilized clorine but it looks like mixing with only sodium cloride is adequate.

 

[jsargent]

Sounds like you're using a patent I've had some success with. If you follow it to the letter things will go well, or at least for me they did. The sodium bromide is essential as the gold-bromide is much more stable than gold chloride. Likewise the sodium borohydride seems to be key as it is a strong enough reducing agent to drop the ORP sufficently to precip your PM's. Nice thing with this procedure is you do the leach at about 3.2-3.6pH so you tend to not leach the iron. Works like a charm on carbonaceous ores.

 

[fixinator]

This started as a simple experiment. It worked so well that I got carried away with it instead of followning procedure and making sure I could get my metals back easily.

I used the peroxyMS instead of 3% H2O2 in the acid peroxide process. Instead of simply flaking off, the gold was dissolving after it flaked off. I figured that once the solution became saturated it would start precipitating. This wasn't the case. It just kept growing and growing. Also the ph was generally about 1 or 2 the whole time so it digested the iron, tin, copper, pretty much everything except the IC chips and the silicon. Although it did show signs of attacking the silicon.

Does this sound like it is close enough to the patent for the sodium borohydride to work? I'm willing to try it. Where can I get some?
What is the procedure for its use?

Fix

 

[jsargent]

This started as a simple experiment. It worked so well that I got carried away with it instead of followning procedure and making sure I could get my metals back easily.

I used the peroxyMS instead of 3% H2O2 in the acid peroxide process. Instead of simply flaking off, the gold was dissolving after it flaked off. I figured that once the solution became saturated it would start precipitating. This wasn't the case. It just kept growing and growing. Also the ph was generally about 1 or 2 the whole time so it digested the iron, tin, copper, pretty much everything except the IC chips and the silicon. Although it did show signs of attacking the silicon.

Does this sound like it is close enough to the patent for the sodium borohydride to work? I'm willing to try it. Where can I get some?
What is the procedure for its use?

Fix

It sounds like you drifted away from the patent quite a lot or you were following a different patent. In any case, now you have mixed-metal soup. Maybe you could reduce/precip the whole mess then use singular acids to pull out specific base metals. Sulfuric should dissolve all the base metals but leave the gold and PGM's as residue. It may dissolve any palladium as well, not sure. Try drying the residue, wash several times with distilled water then HCL+Cl to dissolve the gold. Drop the gold with SMB. You can get sodium borohydride as a product called Boromet from Montgomery Chemicals. I believe they have a 5 gallon minimum. Here... http://www.montgomerychemicals.com/?gclid=CJmM1bqXzJgCFShRagodQihv1g
Best of luck!

 

[jsargent]

This is very similar to caro's acid. I mixed it with HCl and stabilized clorine but it looks like mixing with only sodium cloride is adequate.

Indeed it is more than adequate. When monopersulfate is added to salt water it liberates robust amounts of chlorine. A tad dangerous actually if the pH is too low. In fact when doing a halogen leach, there is no reason to go below about pH 3.0. Lower pH will not significantly improve the process and it will cause the chlorine and worse yet, bromine, to boil off and create a respiratory hazard. Below about pH 1.5 that old devil iron will be dissolved and then you got metal soup.

 

[jamthe3]

Where in Texas are you??

John

 

[jsargent]

Where in Texas are you??

John

Near Austin