i give up ( and im usually not a quitter)

[goldpete]

i have now finnished my 14th batch of AR ( to give you an idea how new i am )
i process computer parts and cell phones
i know for a fact that i have gold in my AR because ive seen so much gold leaf in the filters after i soak parts in nitric.
ill tell you my exact process in a sec so yous can see that im sure i have the process right.

IM HAVING ENDLESS TROUBLE MAKING STANNOUS CHLORIDE TESTING SOLUTION
ive tried so many recipes ive lost count , and the most recent is the recipe from hokes book

first ill explain how ive been processing the material , then ill run through the way ive tried making the most recent batch of stannous
...............................................................................................................................................................
first i soak gold pins and curcuit boards in nitric acid.

then after about 2 days i filter it through 2 coffee filters and i use a spray bottle to keep spraying the contents untill only clear liquid comes out.

after the filter and its contents are dry , i put in in AR made from 40mls of nitric and 120mls of hcl and i stur it well to make sure all the contents mix well in solution.

then after 1 or 2 days i put some sulfuric acid in (approx 20mls) and i place on an electric hot plate to evaporate the nitric slowly on a low heat .
when its reduced to a syrup , i add some hcl and then add to heat again to return it to a syrup. i do that 3 times or untill i get no reaction from adding hcl.

by this time , the liquid is either black or a very dark brown colour . then i add 3 times its volume of hot water. then when cooled , i filter it through 2 new coffee filters.
the liquid that comes out is a nice gold colour and its at this stage that ive tried testing . then i add smb and let it stand.
each time the liquid has gone perfectly clear and i have fine dark dust looking residue on the bottom.
............................................................................................................................................................................
ok now the most recent mix ive tried to make of stannous is :

1 old 100ml bottle that once had cogh syrup which has been boiled in hot water to clean it
1.5 grams of stannous chloride crystals
1.5 grams of tin granuals which i hammered flat
first i tried 25 to 30 drops of hcl but the last time i tried 1/4 of the bottle
and finally 3/4 of the bottle has water.

first i soak the tin granuals in hcl , then add stannous crystals and water then mix and cover with the lid.


EVERY TIME I TEST WITH SOME SOLUTION ON A TISSUE AND ONE OR TWO DROPS OF MY STANNOUS MIX , I GET NO COLOUR REACTION AT ALL
can someone please help me before i throw the whole lot in the bin

 

[patnor1011]

Dissolve in distilled water. Spoonful (small spoon) in 0,1l of water. Add few drops of HCl. Why do you want to add tin in that?
It seems that you have life supply of SnCl2 so you do not need to acidify too much and add tin - that is just measure for prolonging life of your solution. What you need to do is to make some standard solution. Dissolve some foils from fingers in HCl/Cl and put that in small bottle. Now try to test that with stannous.

 

[goldpete]

Dissolve in distilled water. Spoonful (small spoon) in 0,1l of water. Add few drops of HCl. Why do you want to add tin in that?
It seems that you have life supply of SnCl2 so you do not need to acidify too much and add tin - that is just measure for prolonging life of your solution. What you need to do is to make some standard solution. Dissolve some foils from fingers in HCl/Cl and put that in small bottle. Now try to test that with stannous.

the reason i added tin aswel is because i followed the directions in hokes book

before i was able to get some tin granuals , i tried making test solution with just water and crystals . i even tried making a mix with hcl and crystals . as i said above , ive tried so many recipes ive lost count.

what im finding most frustrating is when i read posts on this forum , i keep seeing 2 answers over and over..............have you read hokes book , and have you tested with stannous.

well ive read hokes book atleast 5 times and i cant get stannous to work

 

[lazersteve]

Stannous chloride test (aka: 'Solution A') is very simple to make.

Here are two methods I have had great success with:

Method 1 ( my favorite) -
1) Add 30 mL of 30%+ muriatic acid to 1-2 grams of powdered tin in a test tube with a glass stopper.
2) Allow the tin to react until it no longer fizzes with the stopper off. If a little solid tin remains in the bottom this is ok.
3) Stopper when not in use.

Method 2 -
1) Add 1 gram of white stannous chloride crystals to 30-50 mL of 30%+ muriatic acid in a test tube with a glass stopper.
2) Allow the crystals to dissolve ( may require some shaking of the test tube).
3) Stopper when not in use.

That's it. When the stannous indicates a suspected 'false negative' (when you think it should be positive, but it's not), check the stannous against your gold standard solution. The standard solutions are kept on hand to verify your stannous is working correctly. If the standard solution does not porduce a positive, make a new batch of Solution A.

Steve

 

[goldpete]

Stannous chloride test (aka: 'Solution A') is very simple to make.

Here are two methods I have had great success with:

Method 1 ( my favorite) -
1) Add 30 mL of 30%+ muriatic acid to 1-2 grams of powdered tin in a test tube with a glass stopper.
2) Allow the tin to react until it no longer fizzes with the stopper off. If a little solid tin remains in the bottom this is ok.
3) Stopper when not in use.

Method 2 -
1) Add 1 gram of white stannous chloride crystals to 30-50 mL of 30%+ muriatic acid in a test tube with a glass stopper.
2) Allow the crystals to dissolve ( may require some shaking of the test tube).
3) Stopper when not in use.

That's it. When the stannous indicates a suspected 'false negative' (when you think it should be positive, but it's not), check the stannous against your gold standard solution. The standard solutions are kept on hand to verify your stannous is working correctly. If the standard solution does not porduce a positive, make a new batch of Solution A.

Steve

thanks steve but what is muriatic acid ? is it the same as hcl ? because that all i have besides my nitric and my sulfuric

 

[samuel-a]

goldpete

Pat is right.

A vital part of testing procedure is comparing results to standarts (known samples).
As such, testing known standarts solutions is basically a test for your SnCl2 test solution. It is also a rough indicator for concentration.


From your recovered and REFINED! gold so far, grab one gram exactly and dissolve it with minimal amount of AR or HCl+H2O2 30%.

To dissolve in AR, put the powder in 120 ml test tube and add 5-10 ml HCl and heat the tube from below with a low flame burner (do not boil), then drop in ONE drop of nitric acid and let it react completely. Again, make sure not to boil it, remeber the reaction it self is also exothermic. when the first drop of nitric is no loger dissolving gold, add one more. usually 2-4 drops is all it takes.
The point here is to avoid haveing too much free nitric in the solution. Do this process under the hood.

When the gold powder is gone, dilute with distilled water to make up a 100 ml solution and stir well. Now you have a standart solution with known concentration - 1g/100ml or 10g/liter. To avoid confusion, i'll call this - 'Standart 1'

10 grams per liter is too concentrated standart to work with when doing recovery, so you need to make few more standart solutions.

From your previously made 'Standart 1' solution, using a plastic graduated pipettes, pull 10 ml of solution and put it in another 120 ml test tube. Now again dilute it with distilled water to make up a 100 ml solution. You now have a new test solution with known concentration of - 0.1g/100ml or 1g/liter. Call this - 'Standart 2'

You now can make another sample solution like 'Standart 2', only now, before dilution to 100 ml, add to it a gram or two or more of dissolved copper (in AR).

The possibilities are endless. Play around with concentration and indroduce different contaminants (try even involving PGM's).
Also, It will be wise to try and make a known solution that resembles as much as possible in concentration and contamination to those solutions you are actually working with while doing recovery work.
Matrix Matching

You can make the same solution for Pd and Pt.

Eventually, if a known standart does not yield a colored result to SnCl2 test, then you know you need to replenish your SnCl2 solution.


edit: spelling and additions

 

[ericrm]

have you make your standard test solution? if no,do your homework or stop complaining and using the precious time of the poeple here :x

 

[goldpete]

thanks samuel but all the went straight over my head

 

[goldpete]

have you make your standard test solution? if no,do your homework or stop complaining and using the precious time of the poeple here :x

omg , you didnt just ask that ?
did you even read my first post ?

ofcourse ive done my homework , and this post is about how im having trouble making the test solution .
and im not complaining , im seeking help before i pull my last few strands of hair out

 

[ericrm]

lol im not talking about your stannous chloride solution. im talking about the solution you use to test your stannous chloride and nowhere even if you have been told to make some ,you mention to have make one............ if you did make one plz tell us the result ,if you didnt make one stop asking for help you will not go further in your gold recovery adventure because you refusing to do an important step foward

 

[goldpete]

lol im not talking about your stannous chloride solution. im talking about the solution you use to test your stannous chloride and nowhere even if you have been told to make some ,you mention to have make one............ if you did make one plz tell us the result ,if you didnt make one stop asking for help you will not go further in your gold recovery adventure because you refusing to do an important step foward

i really dont understand what your saying.
making stannous is the most important step that i havent been able to master and thats what im asking help with
and if you read my first post , you would now that i have already discussed both processes that i have tried

 

[lazersteve]

Pete,

Check out the Guided Tour Link below for common chemical abbrevations and names.

Steve

 

[goldpete]

thanks buddy

 

[joem]

first i soak gold pins and curcuit boards in nitric acid.

Is soaking the board wise, is this the whole board with all components?
ALso I make stannous easy, get some tin ( first I bought a piece on ebay, then a member here sent me a life time size bar-which I shared with anothe meber Devo ). Then in a small jar with a plastic lid I put a small piece and HCL. I warmed it on a piece of black metal in the hot sun ( which we had a lot of lately). Works like a charm.

 

[jeneje]

I would offer to send you some already made, but doing that is not helping you to understand the need for it. I don't why you can not make your stannous but Pete you have to slow down and take a break for awhile, what i mean is clear your mind, drink a cup of coffee and then start over with the process and BAM you have it - anotherwards you are trying to hard. Relax and do as lazersteve and others have advised you too and you will master the stannous thing.
Ken
:mrgreen:

 

[patnor1011]

Who knows maybe your powder (SnCl2) is old or it is not what it suppose to be. That is why you need standard solution. To check if your stannous work or not.

 

[goldsilverpro]

Is the stannous chloride white or brown? White is what you want. If stored improperly, it can turn brown and not work as well, or not at all.

Are you pre-mixing your AR or, are you covering with HCl, heating, and then only using enough nitric, in small increments, to dissolve the gold?

If a great excess of nitric is used in the AR, the stannous chloride can initially produce a purple or black color (indicating gold), but this color can immediately and completely fade to no color at all. Try putting a drop of the solution you want to test on a spot plate or white plastic spoon. Add 3 drops of water to dilute it and then add a drop of stannous chloride solution. If gold is present, the color produced should be more permanent.

 

[RESET]

To dissolve in AR, put the powder in 120 ml test tube and add 5-10 ml HCl and heat the tube from below with a low flame burner (do not boil), then drop in ONE drop of nitric acid and let it react completely. Again, make sure not to boil it, remember the reaction it self is also exothermic. when the first drop of nitric is no longer dissolving gold, add one more. usually 2-4 drops is all it takes.
The point here is to avoid having too much free nitric in the solution.

i put in in AR made from 40mls of nitric and 120mls of hcl and i stir it well to make sure all the contents mix well in solution.

then after 1 or 2 days i put some sulfuric acid in (approx 20mls) and i place on an electric hot plate to evaporate the nitric slowly on a low heat .
when its reduced to a syrup , i add some hcl and then add to heat again to return it to a syrup. i do that 3 times or until i get no reaction from adding hcl.

by this time , the liquid is either black or a very dark brown colour . then i add 3 times its volume of hot water. then when cooled , i filter it through 2 new coffee filters. the liquid that comes out is a nice gold colour

While I have never processed gold and may be completely off base, I think the reason your testing is coming up negative is because you have free nitric in your solution. I realize that your repeated boilings and such are supposed to get rid of it but I am not sure how you could test to make sure. Try it the way Samuel says to make known solution and see if your stannous test doesn't work a little better. You may or may not be having trouble making the test solution but without a known standard, you are running blind.

 

[goldpete]

To dissolve in AR, put the powder in 120 ml test tube and add 5-10 ml HCl and heat the tube from below with a low flame burner (do not boil), then drop in ONE drop of nitric acid and let it react completely. Again, make sure not to boil it, remember the reaction it self is also exothermic. when the first drop of nitric is no longer dissolving gold, add one more. usually 2-4 drops is all it takes.
The point here is to avoid having too much free nitric in the solution.

i put in in AR made from 40mls of nitric and 120mls of hcl and i stir it well to make sure all the contents mix well in solution.

then after 1 or 2 days i put some sulfuric acid in (approx 20mls) and i place on an electric hot plate to evaporate the nitric slowly on a low heat .
when its reduced to a syrup , i add some hcl and then add to heat again to return it to a syrup. i do that 3 times or until i get no reaction from adding hcl.

by this time , the liquid is either black or a very dark brown colour . then i add 3 times its volume of hot water. then when cooled , i filter it through 2 new coffee filters. the liquid that comes out is a nice gold colour

While I have never processed gold and may be completely off base, I think the reason your testing is coming up negative is because you have free nitric in your solution. I realize that your repeated boilings and such are supposed to get rid of it but I am not sure how you could test to make sure. Try it the way Samuel says to make known solution and see if your stannous test doesn't work a little better. You may or may not be having trouble making the test solution but without a known standard, you are running blind.

thats exactly what i first thoughttoo buddy , but then i see people say that theyve tested with nitric in and still got results. there was someone ( i forget who) up there who said get 10mls of hcl , put in gold foils and add one or two drops of nitric to make my known . and there was no mention of evaproating the nitric

 

[goldpete]

I would offer to send you some already made, but doing that is not helping you to understand the need for it. I don't why you can not make your stannous but Pete you have to slow down and take a break for awhile, what i mean is clear your mind, drink a cup of coffee and then start over with the process and BAM you have it - anotherwards you are trying to hard. Relax and do as lazersteve and others have advised you too and you will master the stannous thing.
Ken
:mrgreen:

i totally get where your coming from jeneje , and 9 times out of 10 that works for me too.
but in this case , it took me a week from start to finnish , just taking my time with the who process . and then yesterday i took an hour ( yes and hour ) to make the stannous ...... i had notes with me so i didnt forget or leave anything out . i hammered flat 4 new pieces of tin granuals , i wieghd them and the stannous crystals and meashured the hcl .
i even got the right colour , i was told many times it should be a milky white colour and thats exactly what i got. im so impressed with the way it looks that im doubting i have it wrong.
which then throws doubt back to my AR . but its not possible that there is no gold . there was soooooooooooooo much foils going into the AR , and i never spilled any or let it boil , it evaporated so slowly , took 3 days just to evaporate.
thats the one thing i spent the most time with , if there is any nitric in there then i dont know how , i evaporated it down so far that there was only about 20 mls in the coffee pot . i repeated that 3 times and i no longer got any reaction when adding hcl . i even tried adding some more sulfuric and still ot no reaction