SMB

[ViperCV]

Hello,
I've been doing some searching about SMB, but cant seem to find the answer. My question is, If I have dissolved gold, and other base metals in Aqua Regia, and am not looking for pure gold right now, will SMB drop only the gold with minimal base metals...or will it drop everything? I can not find anything with what metals SMB will precipitate.
Thanks,
~Craig

 

[Geo]

sodium metabisulfite is selective for gold. that is why its recommended. SMB creates SO2 in solution which will precipitate gold. the contamination occurs as "drag down", a mechanical process and not part of the chemical process of the SMB.

 

[lazersteve]

SMB also precipitates copper I chloride from solutions containing copper II chloride. SMB will also precipitate Palladium from solution if all of the nitric has not been removed.

Check out the precipitant chart I made:

Precipitants Chart

It's not all inclusive, but it will keep you straight for the common precipitants and solutions.

Steve