How does SMB work?

[Topher_osAUrus]

I must add to that.

I will gladly help you when and where I can, but, BUT, I also want to help you with the safety side of it too.
I want to know that it's being done in a practical and safe manner, where you aren't endangering your life or others.

Everything from proper personal safety gear, down to waste treatment. I want you to set a precedent for other refiners in your country. It's not hard to do at all, and doing it correctly will even give you a bonus in the end, by recovering traces of metals that would otherwise be lost down the drain.

 

[farhad69]

i sent you an email.thx

 

[Chirou]

Well guys, i had beautiful green solution after Poor's man AR with some PCB's without solder i added SMB (not much like a little baby spoon) and everything turned black and nothing changes it's been like an hour.

 

[FrugalRefiner]

Did you test the solution with stannous before you added the SMB?

Dave

 

[bwalyack]

I want to know if smb is selective....I tried to use it and I got a brown precipitate but when I assayed it there was not gold...

 

[butcher]

bwalyack,

Do not confuse recovery of gold with refining gold.
SMB is a great tool in refining but is not a good tool for recovery of gold.

You were trying to recover gold, SMB, in this case, was a poor choice, as you found out SMB will reduce other metals.



SMB is selective for gold when used properly in refining gold, note here we are discussing refining gold.
where most all of the base metals have been removed from the gold in earlier recovery processes, and the solution is fairly clean of base metals.

SMB is used for refining gold, and would not be a good choice in using for recovering gold from dirty solutions.


SMB can precipitate or change the oxidation state of other metals like copper tin...

In a dirty complex of solutions of metals like in a recovery process, SMB is not selective and is not the best to recover gold from these complex metal solutions, copper cementation would be a better choice to recover gold from these base metal solutions.

Recovery of gold and refining gold are two different processes, SMB works great for refining gold but is not much help in recovery of gold from a mess of metals, the more metals in solution the more complicated the mess, and less likely to precipitate gold, if the mess is not too bad, with just some other base metals like copper the gold will precipitate dirty (Black) with copper chloride and other metals, if the solution is mostly base metals and little gold and tin in solution the gold can get locked up in solution as colloids SMB overuse trying to precipitate the colloids can increase the problem, overuse of SMB will reduce copper in solution, and even give a false positive (Brown) reaction to a stannous chloride test of the dirty solution.

 

[nickton]

I think I got that false positive stannous test in my solution, and was wondering what it was. Definitely a brown color, and after letting it all settle overnight, got some precipitate in the form of black powder but still got that weird brown test. I wonder if I should boil it down or what? How does one fix this?

 

[anachronism]

Brown isn't a false positive because the positive for gold is purple/black.

Brown can indicate other metals molybdenum for one. I'm sure one of the pro chemists can add meat to the bones of my post here but suffice to say don't worry about a bit of brown there, take a good look at the raw product you used and work out what other metals could be present.

Jon

 

[nickton]

I don't expect any thing exotic because I kept it simple with this one and just processed gold fingers.

 

[kuli]

Hello.

One dilemma. So if I drop SMB into a solution and previously did not miss the necessary NHO3 gas, can I lose gold with brown steam? Yes or no please

 

[anachronism]

Hello.

One dilemma. So if I drop SMB into a solution and previously did not miss the necessary NHO3 gas, can I lose gold with brown steam? Yes or no please

No

 

[nickvc]

Hello.

One dilemma. So if I drop SMB into a solution and previously did not miss the necessary NHO3 gas, can I lose gold with brown steam? Yes or no please

No

Agreed but bear in mind those fumes are toxic :shock: