Merged Topics on Ceramic CPU Recovery with Yields

[slouma37]

Hi Barren,
no i diden't premix, i put the scrap in a pyrex beacher , i add my HCl 23% 45 mL then my Nitric 11.6 mL immediately and cover with a ceramic that fit the top of the cylindric beacher, so that no gaz can escape and return to solution for maximum effectivness. i check the beacher and let the reaction goes. i started this on my 1.46 Gr last night @ 21:15 and today @ 9 the solution is dark orange and the button still not dissolved.

 

[Barren Realms 007]

You might want to consider adding your nitric in small amounts and see if you helps you.

 

[slouma37]

But Barren i'm using exact amount of nitric given by steve's formula
31 ml / 8mL to dissolve one gram of gold.
and my problem is just this:
Why i'm not recovering 98% minimum of my gold from cpu's and fingers ?
i can incriminate the use of urea to denox AR

and the use of H2O2 added to my AR to reduce fumes also on my batch of powdered Intel Pentium (remember i recoverd 0.17 Gr gold powder from 425 Gr of cpu powder) that's too low. and here i know that 27% h2o2 can dissolve some gold alone wich can't be recovered by SMB.

Thanks

 

[slouma37]

Hi all, i did a huge error now :
i dunno why i forget to filter before putting SMB so after that i decided to filter before the precipitation starts and the result was after rincing the filter , i get the solution yellow without any precipitation and the filter tested with stannic showed positive even if i rinced it very well till it looks white (original color of the filter).
now i'm evaporating my AR diluted with the rince, coz when i put smb i realized that some NOx came off. my Solution was then still UNDENOXED.

 

[philddreamer]

Slouma wrote:
"...and here i know that 27% h2o2 can dissolve some gold alone wich can't be recovered by SMB."

Have you tried cementing with copper?

 

[slouma37]

No never yet Phil, i'll look at some examples in the forum on how and when we use that method

 

[philddreamer]

It is simple, test with stannous chloride, if + for gold, get some clean copper & put it in the solution; let it sit for a couple of days. The gold, if any silver, or platinum in the solution should cement, or drop from solution. even if it test neg for gold, I add some clean copper to the solution & let sit for a while. Then filter the solution, & the sediment I run thru HCl/Cl or AR * follow the standard procedures.

Here is a copy of the reactivity Series: http://www.zephyrus.co.uk/thereactivityseries.html ; become familiar with it, it's a most when cementing.

Check on some post on the topic.

Phil

 

[slouma37]

Ty so much phil for the help.
Just as i deduce, ur a neighbour and i think with such wether we getting last days all reactions goes slow.
1/ It's actually like 4°C, and most of gold seems to take ages to dissolve, i gave it a heat under my fireplace with a candel (+- 60°C ) and the dissolution was all done in like 30 minutes.

2/ even if i did a mistake by putting msb before filtering, i filtered and continue the hit to denox more and some urea cristals dident fizz so i added my smb again and it's now a very nice spongy brown precipit.
i'll wash by harold method, then melt and weigh the button.

the problem is now how to get the rest of the gold from the filter paper ?
aqua reggit all in or, rince till test is negatif and boil the solution before aqua reggit...
thanks

 

[philddreamer]

To recover the gold from filter papers I run the filter thru HCl/Cl. I ussually save the filters until I have enough so I can recover several grams.

Always test your solution after dropping your gold. Save the spent solution & put some clean copper so any pm's left, drop. After a few days, test with stannous cl, if neg. now add some iron. The copper will drop, & the solution is safer to dispose. 8)

 

[slouma37]

Ty Phil for these great advice !
And i got a bad surprise : when washing with Hcl some of the solution turns deep yellow and after syphoning it tests +++ soo dark violet . I guess that Urea was evaporating leaving the No3- in solution that dissolves gold again am i right ? may i use SMB to reprecipite it ? or urea then smb ?

the good surprise : is the rest of gold recovered and washed is great clear tan ,light-brown. i guess it's the 4 * 9 powder.
Thanks

 

[philddreamer]

Yeap, if there's still traces of nitric when you add the HCl you get a weak AR that will dissolve some of the gold. Some urea or heat so you evaporate the nitric, or like Harold's prefered method, add a gold buttom that will dissolve & thus get rid of nitric. Either way will work. Then SMB.

Next time, add your nitric in small increments @ a time.

Nice lite tan is good. .9999 I'm not so sure; but .995+ more likely. 8)

 

[slouma37]

Thank u so much Phil for ur precious help.
Just before i read ur post, i put some 85% formic like 20 mL to c what will happen as it's a reducing acid, but nothing seems to change right now.
I'll take this solution the way u advice me and will report the result.
Thanks again Phil

 

[Anonymous]

There is an even easier way i think to get hold of aqua regis, A new method, with just water and cooking salt. Coldboil NaCl with H2O and the Nitrogen and oxygenin the air will react with it to have HCl + HNO3 + Na... A bird whispered this method in my ear... I guess it works...

 

[butcher]

that would be a weak enough aqua regia to drink. unless cold boil is something special.
if pulling a vacuum boils off water it would also boil off any nitrogen and hydrogen from the air, and IF any HCL, or nitric could form in minute amounts they too would boil off in vacuum, if indeed cold boil is created from a vacuum.

can you tell us more about this bird wispering to you, and give more information? otherwise sorry I am skeptical as usual.

 

[Anonymous]

Haven't you heard of occhams razor, the most simpliest way is often the right one...

Let's say ½-1hour

 

[Anonymous]

Coldboil, all i can say that during the time alchemy was at hand HCl and HNO3 was called spirits of salt

 

[butcher]

http://en.wikipedia.org/wiki/Occam's_razor, never heard of it, but scanning through this its seems double talk to me, maybe my mind is too simple to understand this?

tell us more about this salt water.

Alchemy, I do not know much about it but I thought is was full of witchcraft magic some science and alot of bull to keep people in the dark, science may have origins there but as far as I can see alchemy study today is like trying to go back to the cave days in the dark, and taking your mind into a maze of puzzels with no reason. ther may be some clues to some lost chemistry in that study but you will most likely be lost in the maze trying to find it. personally I would forget that science, and spend what little time I have on earth with real science if that is what interested me. I do not mean any offence but from what little I have read of it it looked like alot of bull to me so I did not look further, tell me more about this salt water, change my mind about Alchemy, maybe it is my mind in the dark in this maize of my brain.

 

[butcher]

welcome to the forum, One_Mile_Shadow, forget what you have learned about metals and alchemy, you have joined the best place in the world to learn about metals and the chemistry of refining them. and from our short discussion I can see you are very smart, and will go far here, If you can get around what you have learned and what you will learn if you stick around here. mixing alchemy and refining you will learn from this forum can give you trouble.

 

[Anonymous]

stop tapping your pigsfeet then...

 

[Barren Realms 007]

stop tapping your pigsfeet then...

That is one saying have never heard.

No need to throw pigs feet in, they have sensative feelings too.

Anyway welcome to the forum, You possibly need to do a lot of reading.