AP question

[aptus]

After watching video #1 about using the AP solution on finders, I have a question. As soon as the solution began to react (after about 15 mins he said) he took the buckets outside due to the fumes ect. He showed how the solution had already removed the gold plating from the fingers exposing only copper left on them. He said the disolved gold was in the solution. If so, why does he let the process continue for about 2 days to get the fingers stripped completely clean of all metals including foil? He shows the end resulting pieces of gold that he rinses but where did they come from as the gold plating was disolved? Is the foil made of gold that is under the copper? I watched all 4 videos and it clearly shows "flakes" of gold. None of the videos told if he processed the solution that contained the disolved gold.

An earlier reply to a question of mine explained the AP process to disolve the copper under the gold so the gold came off in flakes yet in the video he clearly said the gold plating was disolved when he showed the buckets after 15 mins of use. Where are the gold flakes coming from if the plating was disolved? Sorry for such stupid questions but just when I think I have something figured out I get more confused. Thank you in advance-Aptus

 

[Geo]

are you sure you watched the whole video? you should watch it again. the foils do not dissolve in the AP solution,just the copper under the foils.this releases the foils to float loose. you dont want to dissolve the foils at this stage as there is copper still present. read this thread for more information http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=52&t=12914

 

[aptus]

Thank you for the link Geo. I did watch all 4 videos in their entirity. They are on Steves site under ap videos. Its the #1 video shortly after the start where he takes the buckets outside as the reactions have started and he tips the buckets to show the fingers that are just copper in color and he says all the gold plating has been disolved into the solution. Later in the video and in the other videos he clearly shows the flake of gold that I was expecting to see.

My question is simply this. I thought the Ap solution disolved the copper under the gold and if it disolved the gold plating off the fingers like he shows and says, where did the flakes of gold come from? Is there more gold under the gold plating and the copper?

Here is the video that shows it and caused my confusion:

http://www.goldrecovery.us/goldrecovery/videos/ShowVideo.aspx?id=fingersap1&yt=0

 

[Pantherlikher]

You need to read Hoke's book to answer your question in the way you'll understand.
AP is used to disolve copper. HCL and peroxide don't really disolve gold. It would rather disolve the copper underneath, releasing the gold. If he stated it disolves the finger, he probably wanted to say that yes it will disolve some gold untill the solution gets copper impregnated.

I've found just watching every YouTube videob just does not fully qualify as having learned everything there is to know about anything...Like SAFETY!
Ever notice most in the videos never have gloves on.......

BS.
Never a dull moment in a house full of ADHD people...

 

[rheslin2]

an easy way around the possibility of loosing some of the gold into solution, is to mix the hcl and peroxide and only put copper into it, once the copper has impregnated the solution, take the copper out, cut the solution in half and mix 50/50 with water, this will allow the solution to absorb the copper plating under the gold fiols and leave the foils to fall to the bottom.

 

[Geo]

i just watched the videos again to catch what you were referring to. yes, he did say the gold was going into solution but this is not the objective of AP. keep in mind that these videos were made years ago and even Steve has tweaked the process somewhat.by adding too much oxidizer (peroxide) you will dissolve gold. theres no need to add that much peroxide. Steve was rushing the process and he knows what to expect and knows how to deal with gold in AP solution. a beginner should expect the process to take several days to complete. Steve used 2 parts acid to 1 part peroxide and then added extra peroxide. 1 pint of peroxide to 1 gallon of acid will work without dissolving gold. re-using AP solution is another way to keep from dissolving gold.

 

[aptus]

Thanks once again for the answers. Would anyone have any idea where the flakes of gold would have come from as his solution (too strong is sounds like) dissolved the gold plating on the fingers as he said and showed it gone and only copper left on the fingers in his video. (Which was not a you tube and was very informative and addressed safety at every turn) and......

If ones solution was too strong and did in fact dissolve the gold off the fingers, wouldn`t it be useless to continue the process as all the gold is already removed? Why continue to dissolve the copper off the fingers if all the gold is gone? tia-Aptus

 

[Pantherlikher]

I stand corrected but you still should read to find out your answer. Yes it did disolve some gold. But most fingers will just float away and get stuck to something or settle out. I'd guess in the video, disolved gold settled and covered the fingers so you didn't see them. Then stirring, disturbing the settiment, made fingers appear...

BS.
Not 1 person is right about everything, but also never wrong when seeking the questionable.

 

[bswartzwelder]

I too, watched Steves video before starting to work on some fingers and bare circuit boards with AP. I also remember the reference to the gold having dissolved and was going to question it, but never got around to it. With my first batch, I took a drop of the solution when I was ready to get the foils and placed it on a paper towel. I then tested it with Stannous and the results were completely negative for dissolved gold. I used 2 parts of HCl to 1 part H2O2 and it seemed to work very nicely.

 

[Geo]

I too, watched Steves video before starting to work on some fingers and bare circuit boards with AP. I also remember the reference to the gold having dissolved and was going to question it, but never got around to it. With my first batch, I took a drop of the solution when I was ready to get the foils and placed it on a paper towel. I then tested it with Stannous and the results were completely negative for dissolved gold. I used 2 parts of HCl to 1 part H2O2 and it seemed to work very nicely.

the reason for the negative test is any gold that went into solution would have cemented out on bare copper as soon as the copper was available. if you had added more peroxide after the copper was dissolved, there would be no copper metal to cement the gold and there would have been gold in solution. some members use concentrated hydrogen peroxide to dissolve their foils and powders instead of Cl because the peroxide doesnt evolve chlorine gas.

 

[butcher]

Hydrochloric acid HCl mixed with concentrated hydrogen peroxide H2O2, generates chlorine gas CL2(g) in solution to dissolve gold, the chloride in the acid is oxidized to elemental chlorine by the peroxide, to say it another way the H2O2 takes electrons from the chloride (acid) to make chlorine gas, the chlorine gas in solution can now take electrons (oxidize) from the gold, the gold can now combine with free chlorides in the acid to form a dissolved metal salt in solution called gold chloride AuCl3.

This is a bit different than using bleach with HCl to dissolve gold, the peroxide will not neutralize the acid like bleach will, but in a way it works similar.

 

[Geo]

thanks Butcher for the clarification. what i meant to say was, it doesnt evolve the choking, noxious chlorine cloud that bleach makes when dissolved in acid. when i tried it, i barely smelled the chlorine. i used peroxide used to bleach hair.i believe it was around 22%, my memory isnt as good as id like and i didnt keep notes on it.

 

[butcher]

True I normally do not smell the chlorine either.

 

[bswartzwelder]

So, if I understand what you're saying, the gold which dissolved into the solution cemented out onto any copper that was available. I then washed all the foils in hot HCl twice and in boiling water once. I still have the used solution in a bucket (with a lid on it) in a trailer out back. This solution still tests negative for any gold. This used solution was decanted through three large coffee filters and stopped before any solids were poured out. What was left in the bottom of the bucket was poured through another set of coffee filters. These are the foils which were processed through the HCl and distilled H2O baths.

I plan on dissolving the foils in AR and precipitating the gold with SMB. Then, I would like to process by using the Acid/Chlorox method and precipitating with Oxalic acid to get the purest gold possible. Is it necessary to wash the gold between the AR and the Acid/Chlorox dissolutions? Is it necessary to do anything to the gold after dropping it with Oxalic acid? Once I have dry, gold powder, I would like to melt it with an oxy/acetylene torch with a rosebud tip and pour into a graphite mold which has been smoked. I really like the hexagonal or octagonal gold button shown on a member's avatar line, but don't know where to get such a mold.