Silver Refining.This Process involves dangerous acids and fumes therefore safety equipment is mandatory..!!!
Wear Gloves and Eyes Protection and perform outside or in a very well ventilated room or under a fume hood.
1. Start by sorting your keyboards mylars.I'm processing only the transperent type because they have all of the printed silver exposed.
2. With this methode we cut fairly large pieces of the mylar to dip in shallow pyrex vessle.
3. You can do them whole if you like to, and have the appropriate glassware.Meet your new best friends from now on.
4. Fill the dish with only a thin layer, maybe 1/8 of an inch deep with 50/50 solution of nitric acid (HN03) 70% and hydrogen peroxide 3% (H202).I used only 100 ml solution (50 ml nitric + 50 ml peroxide) for dish.The peroxide is used instead of distilled water to suppress any NOx gases.it works..!!!
5.Prepare a rinsing dish to rinse the pieces of treated mylars. For rinsing we will use regular tap water and squeeze bottle.
6. Let's start.Grab the mylar at the tip with a tweezers and slide it in the liquid.I suggest you use a teflon coated or a plastic one unlike me.
7. Within 5-15 seconds you will see a color change some turn lighter almost dissappering and some turn black.When the color is changed completely that means that all of the silver has dissolved.
8. When we are done dissolving the silver, let the mylar drip back the nitric solution as much as you can before rinsing it.It's time to rinse the lew drops that remained on the mylar to our rinse dish.
When rinsing,the dilution of the silver nitrate an the chlorides that present in the tap water immediately precipitate any silver nitrate as silver chloride salt.
9. Note that a dilute silver nitrate create a foggy precipitation of silver chloride as a very line powder that stays in suspension.NO worry,after 24 hours it will sattle nicly on the bottom for you to collect.
Keep going until the you run out of mylar or until the solution is exhausted.
Nitric acid can dissolve great amounts of silver so remember that you probably will not reach fill potential of the acid.
On the good side of the process is that the mylars contain only silver and some lims carbon that does not react. So you don't have to worry about other metals contamination.
10. When you done with the main solution transfer it to a chemical cup.Rinse the shallow dish with a bit distilled water and add to the cup.
11. Solution should be transperent woth no color at all like in the picture and clear of solids (like dust and stuff).If you need filter it.
12. NOW the fun part..!!!! To precipitate the silver as silver chloride we add HCL 32% (hydrochloric acid).
13. It only takes a few ml of HCL to completely precipitate all of the silver.
14. Start driping and watch the magic happens..!!!
15. Drip...
16. DROP...Give a little swirl and let it settle for an hour or two.
And there you have it.your silver chloride in it folffy cottage cheese like form..
I know i haven't showed it but here is the silver chloride that has transformed to elemental silver, dried and ready to be melted.
21.If you wonder about yields..........at this particular batch i processed 24 or 26 mylars and ended up with 4,5 grams of relatively pure silver 99% pure at least.
Labels: Refine Silver from Keyboard Computer
