1 gram in solution - Gold Chloride Clears after SMB - But...

[Photobacterium]

First of all, Many Thanks to LazerSteve and the other many members here who have helped me learn !

After much preparation I have done the acid peroxide process, using 200 mg of gold-plated fingers from AGP, PCI, & ISA cards, along with gold from SD-DDR memory etc.

In the videos, LazerSteve mentions using 600 grams of fingers from ISA cards, yielding 3 grams of gold. Admittedly the plating may be thicker on the ISA cards.

I wanted to test my process before investing a full 3 grams, so I started with 200 grams of cut-off gold PCB fingers.

I got a nice yellow Gold Chloride when I did the Muriatic 35% / Clorox combination on the gold foils. Since I was using 1/3 the weight of gold-plated fingers, I used half of the amounts of chemicals that LazerSteve used.


To describe the details of my SMB solution -

I used 8 ounces of warmed up distilled water & 8 grams of SMB, Sodium Metabisulfite.

I gave it about an hour to mix up & to "just sit there". i figured it was good to be patient.

I looked at threads from a search for "SMB recipe" here at

http://goldrefiningforum.com/

One of the threads implied a 2 grams of SMB per gram of gold ratio. Another thread said, 1 gram of SMB per gram of gold.

I didn't think I had much more than a gram of gold. So, I figured 1 1/2 grams, that would be 1 1/2 ounces of solution, again warmed up, about 90 degrees F.

I mixed that in with the Gold Chloride. It had cleared when I went back to check it, clear like water. Then after another hour I could see like a dark brown smoke, wisps of it, on the bottom. Or maybe like rust on the inside of the 'beaker' (I'm using a large glass measuring cup to hold the final filtered Gold Chloride, and hopefully to do the precipitation.)

But then it just sort of stopped there.


I used Distilled water for all water inputs & rinsing. LazerSteve I think said he diluted his Gold Chloride 3 parts to 1, before adding the SMB solution.

I diluted the finished Muriatic-Clorox solution with the gold dissolved (pregnant solution ?) with an equal part of distilled water. But I don't know exactly how much gold I have. It covered about 6 square inches of multiple coffee filters with multiple layers of very very thin gold foils.

Ambient temperature is about 40 degrees F. That's why I warmed up the solutions, I didn't want to jinx them by them being too cold.

Does the AuCl - SMB precipitation process need a warmer ambient temperature, like 70 degrees F ?

In terms of air pressure, I am at about 1500 feet elevation.


Then I let it go overnight, hoping for some Precipitation. Temperatures dropped to about 30 degrees F. I checked it about 5 AM, maybe 16 hours after initially adding the SMB. The solution remains cleared, with just a tinge or wisp of something on the inside of the measuring cup that holds the clear solution that used to be Gold Chloride.

Anyway, I welcome any trouble-shooting type suggestions that could help me get this sorted out.

I'm tempted to add more SMB, but I thought I should ask for help before plunging blindly ahead.

 

[cnbarr]

I will ask, what I am sure everyone else will ask first, did you test with stannous chloride and what were the results?

Sorry for being short, I'm new to this as well, but it sounds as if you done everything correct, except maybe stannous test? Your solution cleared out and you have a whisp of rusty mud in the bottom, this is your gold, it just might not be as much as you anticipated.

 

[eeTHr]

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In your dissolving step, you used half the amounts of chemicals that LazerSteve used, for only one third the amount of gold. This means that you will have more Clorox remaining in your Au solution.

All the Clorox needs to be out of your solution before attempting to precipitate your gold.

Unlike nitric acid, Clorox will usually evaporate out on it's own. Some people set the solution in the sun for a couple hours, and some people just let it sit overnight. But with your lower temperatures, and having more than usual Clorox in solution to begin with, that won't work as well.

Try warming your Au solution at around 100--120 degrees (don't boil it) until it stops precipitating.

 

[Photobacterium]

Thanks very much for the replies !

I would have to say there is decidely more 'smoke'/brown dust on the inside of the glass measuring cup now, a few hours later, in the cleared solution that used to be yellow.

Yesterday, when I did the reaction, I did it outdoors. All the gold foils from Part 1 (acid + peroxide) dissolved. It was 45 to 50 degrees F but the warming bowl and the measuring cup with the reaction were warmer.

Then, as I was letting it sit, temp's. dropped overnight to just below freezing. The water in the bowl that I originally used to warm the solution was frozen when I went bck to it this morning.

As far as smell, I could smell the chlorine from about 20 feet away, outdoors, yesterday. I hold my breath when I'm closer to the reaction.

This morning there is no chlorine smell from 15 feet away. Still holding my breath & wearing safety gear when I get near the reaction 'bucket', though.


I didn't want to bring the reaction indoors, but I need some electricity, so I set up -
+ Plastic gray busboy tub, inside measures about 20 x 15 1/2" - to catch spills
* Hot plate, low capacity, set at halfway between Min & Max dial setting. The knob fell off, I just have to turn the steel thing it was attached to.
* Stainless steel bowl with water
* Large glass measuring cup with the cleared yellow solution & small amount of brown powder.

I guess I'm getting the reaction. It's just taking longer.

==> Is my SMB recipe OK ? 1 gram of SMB per liquid ounce of distilled water, mixing it up 8 grams to 8 ounces, using distilled water 90 to 110 degrees F.

EDIT - I am hesitant to use myself as a "chlorine meter". But when I was looking at it just now, feeling the temp of the water in the stainless bowl that the reaction cup is in, I took a whiff from about 4 feet away. Zero smell of chlorine.

 

[eeTHr]

photo---

I am hesitant to use myself as a "chlorine meter". Is there some other way to tell if the chlorine has departed the premises ?

Like I said: when it stops precipitating.

8)

 

[eeTHr]

Photo---


P.S. Don't do this indoors, unless you build a fume hood. Harsh chemicals can temporarily disable your sense of smell, and you could be breathing chlorine gas without knowing it.

Even with a fume hood, you shouldn't do it inside a residential building. A shed is recommended.

 

[martyn111]

==> Is my SMB recipe OK ? 1 gram of SMB per liquid ounce of distilled water, mixing it up 8 grams to 8 ounces, using distilled water 90 to 110 degrees F.

Maybe here is your problem, SMB produces sulphur dioxide which is the active ingredient to precipitate your gold. Sulphur dioxide, being a gas, will be driven out of solution at 90 to 110 degrees F, you also mentioned in an earlier post that you made up your SMB solution and let it sit for an hour before using it, during this hour of sitting the SO2 will have been evaporating, so you probably didn't have much SO2 present when you started to use your precipitant.
Personally I use SMB dry, approx 2 grams per gram of gold in solution.

Editted for punctuation

 

[Photobacterium]

I made it a point to re-listen to Steve's SMB video -

http://www.goldrecovery.us/goldrecovery/videos/ShowVideo.aspx?id=smb&yt=0

Yes, 3 times its weight in distilled water before adding SMB.

How does this help the process ? I'm not questioning anyone's judgment, I just want to learn the details.

It makes me wonder if chemical reactions need "space" to occur, the molecule form of room to move around.

Without the water, is it too 'crowded' for the SMB, so it doesn't create the sulfur-ish gas ?

 

[butcher]

“Is there some other way to tell if the chlorine has departed the premises?”
At test for chlorine gas, fill a plastic bottle cap with ammonia, hold it close to the heated solution to be tested, if you see “white smoke” in the chemical reaction of chlorine gases, and ammonia gas, this “white smoke” is ammonium chloride (a positive test for chlorine fumes.
Usually your nose will tell you.
Gases in solutions, cold solutions hold gases much better than hot solutions, heat can be used to drive off the chlorine gas, but this can also form salts (NaCl and NaClO3).

With excess chlorine (oxidizer) in gold solution, the stannous chloride test may not show positive for gold in solution, even if it had gold in solution, (the chlorine may re-dissolve gold in the test and not make the purple of cassius reaction) as a precaution when testing you may take a few drops of solution to be tested in test tube heat to drive off possible chlorine (small volume fast and easy), then test with stannous chloride.

http://www.google.com/#sclient=psy-ab&hl=en&rlz=1R2RNQN_enUS457&source=hp&q=purple+of+cassius+test+for+gold&psj=1&oq=purple+of+cassius+test+for+gold&aq=f&aqi=&aql=&gs_sm=e&gs_upl=21562l30172l1l32500l17l17l1l11l11l4l1172l4641l6-3.2l5l0&rlz=1R2RNQN_enUS457&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=497a0dbec56255c7&biw=1024&bih=535

Water if using HCl/sodium hypochlorite; help to keep from forming salts in reaction.

Dilute solutions will also precipitate silver (dissolved AgCl2 changes into AgCl precipitant) and gold chloride solution can be separated from white silver powder.

 

[Photobacterium]

Thanks Everybody !

I paid $6 for a roll of 96% tin 4% Antimony today.

So now I can make some Stannous Chloride


Is it still called Stannous Chloride if it has the Antimony in it ?

 

[jimdoc]

Is it still called Stannous Chloride if it has the Antimony in it ?

The antimony should end up as black powder on the bottom of your container. You could filter it out or pour your stannous off of it.

Jim