what appen in my ap???

[ericrm]

my mind is bugging me right now
i have found that i have frequently what i think is coloidal gold in my ap.
i alway test with stannous and get negative result(but i have found gold inside my spent ap bucket)
that bring me to a very basis question: does ap disolve gold or not? what is realy happening in my ap?

can someone who have a better chemical understanding than me, explain me, what realy is happening in ap?
let say i have a batch of finger in ap
i put my finger in, put my h2o2 3% ,put my hcl 32% and then what appen inside? (thank you)

 

[Geo]

hcl acid will not dissolve gold unless theres an excess amount of oxygen.H2O2 is just water with an extra oxygen atom.when you add the H2O2 it is to create a small amount of copper chloride, but for the first fraction of a second it attacks the first metal it comes to which is the gold (thats where the yellow color comes from when you first add it).because gold is higher on the reactivity scale as soon as the extra oxygen reaches the copper it stops attacking gold because the lowest metal on the scale will dissolve first, then the next highest and so on till it reaches the point that gold is the only metal left.thats why its a bad idea to keep adding H2O2 to your AP after the first time.if base metal is present after the initial few seconds of adding H2O2 any gold in solution will cement back out as powder.

 

[ericrm]

ok if i understand you righ
once my ap is over my finger
ap attack gold AND copper until there is no more free oxygene
than gold ciment over coper (and give my misterious colloidal gold)
than copper chloride ...... ---i dont understand what is happening here---.......
than my ap is full of copper chloride
and my gold flake are free

 

[Geo]

hcl acid will not dissolve copper but copper chloride will.AP works by converting the copper to a copper oxide and then the hcl dissolves the copper oxide and converts it to copper chloride.for the process to move forward there has to be free oxygen in the solution for the copper chloride to work with (that's why we add the bubbler).without oxygen the reaction will stall and no more copper will dissolve. in Steve's videos, he adds oxygen by periodically adding peroxide.when processing several pounds at a time you must incorporate an oxygen supply or your wasting your time.

 

[Palladium]

What you may be seeing is very, very, very fine pieces of gold that remains sometimes if you don't rinse your plastic REAL good or filter well. What did you filter with? If it was a coffee filter then i would say you stand a chance of it being gold plating and not colloidal gold. It can be just as much as a pain in the @#* though.

 

[ericrm]

i rarely filter
what i usualy do is (with finger) get them in ap,remove finger
rince gold foil and crap
get hcl-cl with foil and crap
filter
drop with smb
hcl-cl
drop with smb
be an happy man

edit i dont write the rince in hcl and water....

 

[nickvc]

I'm not an expert on e scrap by any means but as your AP solution is not going anywhere any gold in there will at some stage be recoverable. If you feel you have reasonable quantities of fine gold powder in your solution I would decant it making sure you don't disturb the sludge and then filter through the well respected and cheap charmin plug, recover your AP and then rinse the plug with water, dry the plug, incinerate and then refine the residue. If I'm wrong about this method I'm sure one of our more knowledgeable members will correct my thinking, as I said before e scrap is not something I ever really dealt with, especially using the methods in common use on the forum.

 

[joem]

ok if i understand you righ
once my ap is over my finger
ap attack gold AND copper until there is no more free oxygene
than gold ciment over coper (and give my misterious colloidal gold)
than copper chloride ...... ---i dont understand what is happening here---.......
than my ap is full of copper chloride
and my gold flake are free

I don't know if you got an answer to this but if you want to follow my attempt from last summer here it is
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=61&t=9862