processors

[arthur kierski]

after extracting gold from processors, i pulverized these processors in a mill.----i took 367grams of this powder and added to it 300cc of hcl +100cc of h202(130volumes=35%)---i put the h2o2 by parts so that the solution would not boil over---the solution became red and after boiling it i filtrated and to the filtrate i added zinc powder and a black powder was precipitated---when i dried the black powder it became brown(not magnetic)--might be gold or palladium--------but what i need help to understand is:usually whem i add zinc to a chloride solution,the solution becomes white(water collor)---the solution became green(i think it is fecl2)----should not zinc precipitate iron and the solution ( zncl) becomes white(water color)? or zn does not precipitate iron??this is not the first time that this happens-------------------by the way,the brown powder obtained wa 0.63grams or1,71grams per kilo

 

[lazersteve]

Arthur,

The red extract is indicative of Palladium.

Did you test the extract liquid with stannous chloride before adding the zinc?

Zinc is above iron in the activity series chart, so it should precipitate the iron. High acid levels may redissolve the fine iron if the solution is not saturated with zinc.

Typically my zinc precipitate left overs are clear to very pale green.

If you treat the zinc precipitate with hot HCl most of the finely divided Palladium (if present ) should redissolve and the gold will not.


Steve

 

[arthur kierski]

steve,as usual (my great mistake) i did not test with stanous chloride--tomorow i will do the powder with hot hcl to see what happens and then pass to you---i have many kilos of powdered processors and tomorow i will repeat the experiment--AND test with sncl2--as the green solution i think you are right because it was very acidic and redissolved the iron

 

[Anonymous]

I read somewhere while studying up on refining that iron will not precipate, not sure if that applied only to water solutions only.

Jim

 

[arthur kierski]

james,i also read somewere that iron in some conditions does not precipitate--as i wrote in the thread --it was not the first time that this happened