# precipitates with smb



## arthur kierski (Dec 17, 2011)

i have an Ar solution with some gold-----i expect 3grams of gold( this is an example) ,so i add 3grams of smb-----the brown gold precipitates is 7grams-----what is the additional 4grams of brown material? this happens often to me------what is smb precipitating additionally with the gold?
thanks for coments?
Arthur


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## qst42know (Dec 17, 2011)

What metals might be in this AR solution, base or precious?


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## arthur kierski (Dec 17, 2011)

qst, base metals in the ar solution----


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## qst42know (Dec 17, 2011)

Something that precipitates with the gold, but not palladium?

At what point does this material get removed?


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## arthur kierski (Dec 17, 2011)

this material is basically done with 2 ar process-----the first ar is tested with stanous chloride and the results is blank(no precious metals)-----the second ar gives a very deep purple black with stanous----- lots of gold------after precipitating with the smb and testing with stannous the solution again give blank results


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## arthur kierski (Dec 17, 2011)

the first ar cements gold on to the base metals----the 2nd ar puts gold and remaining base metals into the solution


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## qst42know (Dec 17, 2011)

I take it this solution is from cell phone chips.

The material in question follows through both AR treatments?


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## arthur kierski (Dec 17, 2011)

from cellphones chips and other boards chips------of course separated ----board chips or cellphone chips----the problem arises in board chips(cards,mother boards-----less in cellphones chips


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## qst42know (Dec 17, 2011)

There are a bunch of fillers used in the plastic compound the packages are cast from. Perhaps this problem is related to one or several of them?

It does go away on the second AR treatment?


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## steyr223 (Dec 18, 2011)

Hi guys
Hope your Xmas. Is good
now I know I'm new but

2 Ar processes 
Dud I miss somerhing
Hey not to get of subject
Geo
did you ever get an answer. About the
Sulfer dioxide from Dr Poe
thanks steyr223


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## nickvc (Dec 18, 2011)

There are occasions when dissolving base metals with values in AR can be used to advantage, it's a trick that needs good understanding and constant monitoring as you dissolve all the metals including the values but stop before all the base metals are consumed which allows the values to cement back out leaving a barren solution but always test for values before discarding. Harold has a post about this very procedure, it's rarely used but can have it's place in our processes.

Corrected for spelling inaccuracy...


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## arthur kierski (Dec 18, 2011)

Nickvc-----it is precisely what i try to do with the 2ar system-----
regards, 
Arthur


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## arthur kierski (Dec 18, 2011)

qst, the liquid tested in 2nd ar gives blank with stannous---- always till now
regards,
Arthur
it is not the first time that i write a thread about precipitating more powder with smb then expected-----and until (if the forum permits) i will not find a reasonable answer,i will continue with my questioning. 
by the way, i try all sugestions(solutions) given to me
regards 
Arthur


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## arthur kierski (Dec 18, 2011)

the liquid from the 2nd ar gives pms when tested with stannous and blank after precipitation the gold with smb


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## Dr. Poe (Jan 5, 2012)

arthur kierski said:


> i have an Ar solution with some gold-----i expect 3grams of gold( this is an example) ,so i add 3grams of smb-----the brown gold precipitates is 7grams-----what is the additional 4grams of brown material? this happens often to me------what is smb precipitating additionally with the gold?
> thanks for coments?
> Arthur



Tellurium. Dr. Poe :|


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## Harold_V (Jan 6, 2012)

Dr. Poe said:


> arthur kierski said:
> 
> 
> > i have an Ar solution with some gold-----i expect 3grams of gold( this is an example) ,so i add 3grams of smb-----the brown gold precipitates is 7grams-----what is the additional 4grams of brown material? this happens often to me------what is smb precipitating additionally with the gold?
> ...


If that be the case, shouldn't it be driven off as red fumes if incinerated? (Or am I thinking selenium?)

Harold


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## kurt (Jan 6, 2012)

Arthur - what are you basing the "expected" return of 3 grams on - another words is it possible that you are getting a better then "expected" return.

Chips can vary a lot from batch to batch as not all chips are created equal.

Kurt


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## Anonymous (Jan 6, 2012)

Was this pure smb,it did it contain sodium hyposulfite(as in Super Rust-out)?If it did not contain sodium hyposulfite,is it possible it contained anything else?Have you checked the solution with stannous to verify that it is barren?Have you checked the precipitates,to verify that it is gold?


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## qst42know (Jan 6, 2012)

This page lists some of the inorganic fillers that might be included in chip packages. 

Antimony perhaps? A couple are calcium compounds. I seem to recall (from the forum) under certain conditions calcium can cause problems?

http://www.mdacomposites.org/mda/psgbridge_cb_materials4_other_constituents.html


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## arthur kierski (Jan 6, 2012)

the precipitant is smb----- perhaps i did not explain well----i am not assuming nothing-----what i am saying is : i have an ar solution with gold chloride in it----when i add smb to it,gold precipitates and wth the gold another powder precipitates together-----by my thoughts, only gold should precipitate----- i do not think that it is telurium---the gold comes from plated (fantasy jewllery), or black ic or processors(ceramic)-----the material which i work with,usually is put in nitric to eliminate ag , pd and base metals and then after washings the powder left , it goes thru ar-----the example given is just to try to explain better--- 3grams of smb (i learned in the forum) would precipitate 3grams or 4grams of gold----not 3 grams or 4grams of gold plus 4 or 5grams of other things-----thanks and regards, 
Arthur


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## Geo (Jan 6, 2012)

thats just it,SMB is pretty selective. nothing else should precipitate BECAUSE of the SMB.have you tried the process and waited the amount of time taken without adding SMB to see if anything self precipitates due to other factors,temp change maybe.have you tested the extra weight to see what it is? since it came from AR, then AR should dissolve it and test for values. have you tried to dissolve any of the powder with hcl/cl to see if any solids are left behind.


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## Dr. Poe (Jan 6, 2012)

Harold_V said:


> Dr. Poe said:
> 
> 
> > arthur kierski said:
> ...


Yes, Harold, you are thinking of selenium. Remember that they usually occur together. Dr. Poe


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## arthur kierski (Jan 7, 2012)

Geo,thanks for the recomendations----some of them i did---others i will do and pass to you what happened-----
regards 
Arthur


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## g_axelsson (Aug 24, 2013)

In my quest of reading every post on the forum I ran into this one which I think I could add some ideas to.

Arthur, did you ever discover where the extra weight came from?

I have run into a similar problem when precipitating gold from dirty solutions and forgetting to get rid of led before filtering the gold chloride.
I have an idea of what happened, the SMB is quite specific in precipitating gold from chloride solutions as it is producing SO2 that precipitating the gold. But the SMB also creates sulfuric acid or at least sulphate ions in the solution. If you have dissolved lead chloride SMB will precipitate lead sulphate with the gold. When mixed it can be hard to see that the powder consists of brown gold and white lead sulphate.
If there still is some nitric acid SMB can also precipitate a palladium salt.

In my case I only needed to redissolve the gold, filter and precipitate it again with SMB. The second time it came out decent, less than I wanted but close to expectations. :mrgreen: 

Göran

Edited : Changed chloride to sulphate where I did an error. No one else caught my mistake so it doesn't affect the following posts.


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## arthur kierski (Aug 24, 2013)

Goran;you are correct-----the excess powder is(was lead,silver and some more gold)----i did almost all the sugestions in the threads,and concluded ,what you have found in your experiments----

thanks and regards
Arthur


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## JHS (Aug 25, 2013)

Hi Arthur,
this may or may not sound dumb but,are you sure that you calculated the gold amount correctly.
is it possible that there is more gold than you expected.
if it's all brown,i would melt it,just to see the results.
just a thought.
john


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## arthur kierski (Aug 25, 2013)

JHS,unfortunatelly the gold found was only what was found-----
thanks and regards
Arthur


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