OMG said:Also, if caro acid can oxidize carbon, would it be able to oxidize gold?
I'm experimenting and gathering data mainly.
Caro's acid/Sulfuric acid mix is attractive because it will dissolve most base metals as well as sulfides. Sulfuric acid is the cheapest usable acid I know about, as well, the caro's part of it can be (re)generated by electrolysis of the solution. Also... I think it would be easier to regenerate the spent acid as well.
Caro's acid is very powerful, but if I decide to use it, I will be only making enough of it to do its job (possibly even making it using electrolysis right in the tank where it will be used), at which point it is used up and is no longer caro's acid, just metal sulfates.
Also, on another note, I'm looking into it as a method to produce ozone in enough quantity so I can try to oxidize ammonia to make my own nitrates.
All this experimenting and stuff is my hobby, I've found that I enjoy learning chemistry quite a bit. (much more than back in high school). Once I learn enough I will start refining (maybe even as a source of income).
Reading says that gold is not oxidized by caro's acid. But I would definitely have to test that out because H2O2 oxidizes gold enough to dissolve it, and caro's acid is just sulfuric and h2o2.
How you stable ph at 3+ while having orp more than 800mv?Caro's acid,(or peroxy monopersulfate, the potassium salt of it) WILL dissolve gold if your leach solution has sodium chloride or sodium bromide in it. Copious amounts of chlorine/bromine is produced forming gold halide. According to the literature, however if your ORP is too high (too oxidizing) then a layer of gold oxide will passivate the gold and prevent further dissolution. Shoot for 850mv and a pH of <3.8
Also, forget about using stainless steel anywhere in this. Eats it right up.