Silver from xray flim

[mda20]

Actually I get difficulty in melting because I have to add the following:
Sodium Nitrate %100
Borax %50
Soda Ash %25

Sometimes I succeed but mostly the crucible was damaged.

The sodium nitrate is needed to oxidize the carbon but this reaction destroys crucibles. If you were to incinerate to white ash (no black) before melting, as Sena has done, you wouldn't need any sodium nitrate, at all, and, therefore, you wouldn't damage the crucible nearly as much.

Thank you goldsilverpro for these precious info.

I heat the sludge hardly to red hot temperature, but the result is black powder not white!

 

[goldsilverpro]

I just reread the thread and found that you are using oxalic acid. I have never used it. Maybe Manuel will respond.

 

[mda20]

It is the first time I use oxalic acid. I have gotten this from Manuel and so far the process not finish because I have to dry the sludge. In this way I wonder if drying under the sun is enough?

Regarding to caustic soda process, if I go to this process, I will try your process and Sena`s process in melting.

Thanks to you GSP and to Sena.

 

[mda20]

Dear Manuel,

Good day.

Regarding to oxalic acid process, now the silver compound is dry ( It has been dried under the sun).

Shall I add any chemicals with melting?

Regards

 

[Juan Manuel Arcos Frank]

mda20:

I offer an apology because I was in Mexico City doing some business and I could not answer you soon.

Look,oxalic process yields to pure silver,there is not need of any flux...anyway...if you are not getting metalic silver from your black sludge then you can use some potassium nitrate(saltpetre) as flux,melt the black sludge with its same weight of saltpetre,when it is liquid add a pinch of saltpetre until you get metalic and white silver.

Look at your process,there is some contamination that is causing you problems.

Would you mind to tell me,step by step,all you have done?

Kindest regards.

Manuel

 

[goldsilverpro]

mda20:

I offer an apology because I was in Mexico City doing some business and I could not answer you soon.

Look,oxalic process yields to pure silver,there is not need of any flux...anyway...if you are not getting metalic silver from your black sludge then you can use some potassium nitrate(saltpetre) as flux,melt the black sludge with its same weight of saltpetre,when it is liquid add a pinch of saltpetre until you get metalic and white silver.

Look at your process,there is some contamination that is causing you problems.

Would you mind to tell me,step by step,all you have done?

Kindest regards.

Manuel

He's using sodium nitrate and it's chewing up his crucible. How would potassium nitrate be any different?

 

[mda20]

Thank you dear Manuel and welcome back.

The process was:
-500 gm of Oxalic Acid added to 10L tap water.
-Solution heated to about 90C in steel container.
-3 kg of films submerged in the acid solution.

The result:
Nothing happened. Films still black, no reaction.

The process is repeated as the following:
-The films were removed from the solution.
-The solution is re-heated to higher temperature.
-The same films were re-submerged in the solution.
-The black stain was removed by ribbing.
-After 3 days the sludge settled down.
-Sludge collected and dried under the sun.

The result is black power as in the picture.

Best Regards.

 

[sena]

whats the weight ?

 

[Juan Manuel Arcos Frank]

GSP,My Dear Friend:

There is no difference between using NaNO3 or KNO3,the difference consists in adding the flux once the contaminated silver is liquid,the reaction that takes place whitens the silver.

Crucibles have to be cured,here is how I cure them:

Dip the original crucible in tap water for a few seconds.
Pick up the crucible and put it upside down
Heat the crucible with the torch for a while
Put the crucible upside up and add some dehydrated Borax
Melt borax and cover all the crucible with a liquid glass film
The crucible is ready

Of course,crucibles do not last lifetime but they work better if they are cured

Have a nice day

Your friend:
Manuel

 

[Juan Manuel Arcos Frank]

mda20:

Black powder seems to be OK,let us take a look to the vessel,What kind of stainless steels is?

 

[mda20]

Here is the steel container.

The black power is about 30 gm.

 

[Juan Manuel Arcos Frank]

GREAT HEAVENS!!!!!!!!!!!!...that pileup is not made with 316 stainless steel!!!!.

This is the source of all your problems because it is dissolving slowly(and forming an iron salt that could form a colloidal solution).Oxalic acid solution are used as rust remover.You must change your vessel,get a 316 type one.

Now,the black mud could contain some iron salts,melt it and make shot,process it(for this time) with Karo syrup process or nails process to obtain your silver.

As soon as you use a 316 SS vessel you will get pure silver without any problem.

Keep us posted about your progress.

Kindest regards.

Manuel

 

[mda20]

Thank you very much Manuel.

Is there an other choice of vessel? I mean can I use an other metal or glass vessel instead of stainless steel?

 

[Juan Manuel Arcos Frank]

Yes,Sir...you can use PYREX glass.

If you buy a new 316 vessel then it would be very expensive,but you can get an used one very cheap.

Check in junky yards,look for an old photo processor or an old X Ray processor,they are made with 316 stainless steel.I have never tried aluminium,make a test,process a few films in an aluminum vessel and see what happens.

Keep us posted about your progress.

Kindest regards.

Manuel

 

[Lou]

Don't use aluminum! It reacts with caustic (or oxalic acid) to produce hydrogen gas!

 

[mda20]

Thank you Manuel for your help.

I will repeat the process and let you know what will happen.

To Lou:
Thank you for your advice. I will not use Aluminum.

Best Regards,
MDA20

 

[Juan Manuel Arcos Frank]

Thanks,Lou!!!!!
Kindest regards.
Manuel

 

[A_mitra]

The process was:
500 gm of Oxalic Acid added to 10L tap water.
solution heated to about 90C. And scrub and got mud.
Now melting prossage: I have a great problem.
Heat coal Add mud to a iron container, add borax/Na2CO3/CaCO3 step by steep but after ½ hour it was very har.

I need your kind help step by step mathods and how much gram borax/Na2CO3/CaCO3 will add.
Like i add mud in to the iron container then heat then add borax/Na2CO3/CaCO3.
When I will add. I tried many itmes but I am unable to do.

I am keenly requested t solve my problem.

Thanks
Previous

 

[Juan Manuel Arcos Frank]

A-mitra:

Not that fast...first of all you have to heat oxalic solution and films to 95 C for 20 minutes,at least.If you heat to 90 C chemical reaction between oxalic and gelatine does not take place.

To melt silver you need to reach 1000 C,so you need an oxygen/propane torch or a convection oven.

You do not need any flux but if you want to use any then use potassium nitrate.

Kindest regards.

Manuel

 

[kjavanb123]

Hi,

Does oxalic acid method work on both types of x-ray films? Halide. And other type? Because, I have tried this method on a MRI type of films and nothing happened.

Thanks
Kevin