Did not dilute my SMB drop.

[Nopyrite]

Hello, all was going well in my quest for shiny metal. I had carefully followed instructions using Steve's Acid Peroxide formula and had successfully dissolved about 400 grams of Gold plated PC boards. I had a nice little batch of HCL and water washed (multiple washes) foils in my filter. I then dissolved the foils in HCL/Clorox. In the next step I attempted to drop the Gold using SMB. The result is very disappointing. A very thin layer of brown stuff has settled into the the bottom and the the solution still has a dark cloudy look. The one thing I missed was the instruction to DILUTE solution 3 times before dropping with SMB. I did not dilute at all. My question is: Where do I go from here with my botched "drop"? I have the dark solution and settled stuff in a glass coffee pot. Any help will be greatly appreciated.

 

[butcher]

the brown powder is gold, have you used stannous chloride to test your solution, also if you still have free chlorine in solution it can keep gold dissolved, and if chlorine keeps gold dissolved your cstannous test may not precipitate gold either, sunlight or heat will rid free chlorine from solutions.

 

[Nopyrite]

Thank you for your help butcher. I let the pot set out in the bright sun light for a day. I just did a stannous test on the liquid and am not sure what the results mean. I have included some photos. If you get a chance to look at them I would be grateful. The dark end of the swab was the test of my stannous with a known gold solution. The lighter end is from the pot. The black powder in the bottom swirls around very easily and does not seem heavy as I was expecting. Should I attempt to siphon off the liquid? Once again thanks for your help.

 

[Nopyrite]

butcher, i forgot to mention that the solution cleared up quite a bit after sitting in the Florida sunshine. Thanks for that little tid-bit. Also, it has been a couple of hours since I did my stannous test. I just took another look at the swab. The known gold end is still dark, but the other end seems to be loosing color as time goes by.

 

[Harold_V]

The test with stannous chloride is very sensitive, therefore it responds to even tiny traces of gold in solution. If, after testing, you find that you don't have a prominent purple color, you can safely assume that the solution contains so little gold that it isn't worth any effort. That is assuming you do not have an abundance of nitric acid in your solution, which can interfere with the reaction. Note, also, that if a solution is absent of yellow, there's a pretty good chance it's barren. The color, of course, is a viable method of making a determination only when there are no other elements in solution. Color alone can be misleading. The presence of copper, nickel or iron will yield colors that confuse the mind. They do not present an obstacle when testing with stannous chloride, however.

Harold

 

[Nopyrite]

Harold, thank you sir. I have only been a member here for a few months, but my knowledge of the correct processes taught here continue to expand. Prior to finding this board, I had tried a little refining, but without proper guidance, I just made things messy. Harold, are you the one here who advocates "incinerating" some items prior to treating with acid? If so, perhaps you can advise me on some Gold plated items I have. These items have tiny white printing which does not go away in the AP process. They just float around with the foils. I will post a picture and maybe you can advise me as to a solution.

 

[Harold_V]

Harold, thank you sir. I have only been a member here for a few months, but my knowledge of the correct processes taught here continue to expand. Prior to finding this board, I had tried a little refining, but without proper guidance, I just made things messy. Harold, are you the one here who advocates "incinerating" some items prior to treating with acid? If so, perhaps you can advise me on some Gold plated items I have. These items have tiny white printing which does not go away in the AP process. They just float around with the foils. I will post a picture and maybe you can advise me as to a solution.

Indeed, I am the one that harps on incineration. Frankly, I'm mystified why others don't advise the same thing. Incineration tends to solve all problems, coupled with the appropriate HCl wash when necessary.

Harold

 

[g_axelsson]

Frankly, I'm mystified why others don't advise the same thing.

We don't have to, you are doing such a good work! :lol:

/Göran

 

[Nopyrite]

Harold, great, check these out please. I have a few lbs that I would like to process. The foils in the filter were a trial run. When they were still in solution, the mash looked like "alphabet soup" with all those little letters and stuff floating around. If you look closely, you can see the dried foils are saturated with those little rascals. I decided to do no more until I could figure out how to get rid of the white stuff. Do you think these pieces would be a good candidate for incineration? I am just a small time retired guy down here in Florida. I have always had a fascination with all things Gold related and am now able to play and enjoy my "Golden" years.
P.S. I only have a little MAPP torch at this time, would that be adequate?

 

[lazersteve]

Dissolve the foils with HCl-Cl and filter out the solder mask/ silk screen trash.

Steve

 

[texan]

After dissolving the gold foils in HCl/bleach and then filtering I have found a second round is useful. A less robust auric cloride will be formed and the trash goes to a bin to be incinerated in the future when enough material is collected to make it worth the time.

I hope to be able to display my first button soon...right now I have a nice flask gradually filling with "brown coffee grounds" but no way to do a "melt."

Birthday coming up soon...I may tell the wife I need a decent welding rig to help keep the back yard furniture in good repair.....

Texan

 

[butcher]

Texan that is a good way to get a torch for your birthday.

although dont tell your wife you can melt the gold in a small fire brick furnace and a Mapp gas torch and a melting dish, you can see lasersteve's web site for the fire brick furnace and dish, he also has video's if you havent seen them.

 

[Oz]

Although it is pushing the limits of insulation I think Noxx melted some gold with just propane when he was just starting out.

It is worth saying that although many of our women think we are nuts (ok, maybe I am) once they see buttons or bars of precious metals they want them for themselves and wish you to make more. After all it is easy and just a hobby for you, right?

 

[Harold_V]

Harold, great, check these out please. I have a few lbs that I would like to process. The foils in the filter were a trial run. When they were still in solution, the mash looked like "alphabet soup" with all those little letters and stuff floating around. If you look closely, you can see the dried foils are saturated with those little rascals. I decided to do no more until I could figure out how to get rid of the white stuff. Do you think these pieces would be a good candidate for incineration?

Indeed I do, and it is far better than processing and eliminating them in filtration. Incineration is truly the magic bullet of refining. You never know what is contained in a lot of recovered values, some of which can be troublesome. Traces of oil, for example.

I only have a little MAPP torch at this time, would that be adequate?

You would be far better served to have a small hotplate. An electric one will serve the purpose, but you will render one that is good, not so good for future use in the kitchen. Use one you don't cherish. Use a small stainless fry pan, which can be procured from any of the second hand stores. Boy Scouts had a tiny fry pan that is ideal for small lots. Heat to dull red, which will ignite any carbonaceous material. If you have an oxygen bottle, when the material is hot (do not melt), play a little oxygen on the surface (very small amount, at low velocity, so you don't lose the foils). Any combustible material that is present will glow. When all has been consumed, you can really guild the lily by giving the material a wash in HCl before dissolving and filtration.

These small steps tend to yield a much higher quality of gold. Whether they are worth the effort to you, or not, is a personal decision. You can process without any of it, removing the unwanted material in filtration. That was never my choice. Nothing went through my system without first being incinerated, or being melted (inquartation). I had no issues with unwanted substances that way.

Harold

 

[Nopyrite]

Harold & Steve, you guys are as the kids say, "DA BOMB". Thank you, thank you, thank you. Steve, I will use your method on the dried foils. Harold, your frying pan suggestion has me all revved up. I have a small hot plate in my shed and a bottle of Oxygen came with my Mapp, which I have never used. Lets see, I have the hot plate, the oxygen, some golden items. Next I find some Boy Scouts cooking their dinner, I mug them and steal their frying pan, WOW, this sounds like fun. Just Kidding!! Harold, one little clarification. The purpose of the oxygen: Is it to aid in the combustion or just the low pressure to keep the foils from floating out of the pan? Thanks again guys.

 

[rewalston]

Steve I have a quick question for you. When our gold foils, powders, etc. are placed into solution utilizing HCL/CL can a person collect the auric chloride and keep adding to the solution. What I mean is, can I use the AUCL as a collector of sorts until I get a nice blood red solution and then process it at that time? If so what is the theoretical limitations of HCl/Cl for dissolving gold into solution? Does this make any sense?

Rusty

 

[lazersteve]

Theoretically yes, practically no, you may be better off dropping the gold from each batch and refining it all a second time in a much smaller amount of Poormans AR to get that nice red solution.

The main reason is because by reusing the pregnant solution you risk cross contamination and secondly you may very likely end up losing gold to any debris, sludge, or filters it comes in contact with along the way.

If you want to stretch your chemicals try not being so heavy handed on the oxidizer and calculate the proper amount of HCl ahead of time.

Here's a post of how much gold HCl-Cl will hold:

Saturation of HCl-Cl

It was fun to do the hypothetical math, but in reality you and I will likely never achieve, or even truly know, the theoretical limits.

Steve

 

[Harold_V]

The purpose of the oxygen: Is it to aid in the combustion or just the low pressure to keep the foils from floating out of the pan?

It acts as an indicator, and accelerates combustion, assuming it isn't complete. You have to use good judgment, as the foils are easy to blow out of the pan.

If you are at the proper temperature (in excess of 1100°F, carbon will burn. Providing oxygen will give it cause to glow brightly. If you don't see that reaction, either the combustion is complete, or you are below the combustion point of carbon. Very reliable method to use when incinerating polishing wastes from the jeweler's bench.

Harold

 

[Nopyrite]

Harold, I dug out an old Stainless Steel pot and gave it a go, but it looks like my method needs some fine tuning. I have posted some pictures for you to check. I never got to the oxygen stage as the smoke and smell caused me to shut down the operation. One of my problems may have been my choice of cooking pot. I placed 5 pieces in the pot and they did not all heat at the same rate probably due to the pot not having a flat enough bottom. Some of the pieces got so hot that they started to de-laminate. I believe the bonding material which started to melt was the main cause of the smell. Notice also that some of the plated metal completely separated from the fiber boards. Do you think I should have let it keep going and not shut down so quickly? I still like the incineration approach.

 

[Nopyrite]

Here are two more pictures I forgot to attach.