Too much SMB

[Moo]

Hi forum
I just finished adding some SMB to a solution of gold chloride I made from sweeps, upon adding the smb my thinking was a couple teaspoons cant hurt turned out though when I weighed it that a teaspoon was 2 grams and I added 3 the solution cleared and I went for a walk for a while upon returning my solution was slightly yellow again and a somewhat flaky in form powder can be seen on the bottom although not much about a gram or 2 max id say, I tested the solution with stannous and am getting a orange result, As far as im aware this cannot be relied upon however if too much SMB is added how to proceed? pics of stannous test before and after attached.

 

[lazersteve]

Sweeps may contain platinum group metals.

To be sure you are not getting a false positive you must heat the solution to drive off the free SO2. Once the SO2 is gone retest and see if you get an orange or orange that changes blue-green. Orange would indicate platinum, if it changes to blue-green test a small sample with DMG to see if you have Pd present. If Pd is present a fluffy yellow precipitate will form with DMG. Let this precipitate settle and retest the liquid with stannous chloride for Pt.

If Pt or Pd are present then add to the stock pot for recovery later using copper.

Steve

 

[Geo]

the SMB is dissolved in water and then decomposes into SO2 and salt. if you warm the solution, the SO2 (which is a gas) will escape the solution faster. it will evaporate on its own, but may take some time. by heating, it will drive the gas from the solution. bring it to a slow gentle boil for 15 minutes or so and then allow it to cool.

 

[Moo]

Thanks Guys, heated it till it started to boil then lket sit for 10 hours and still positive will add to stock pot