Mylars again

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ybotptl

New member
Joined
Mar 27, 2017
Messages
4
So there I was minding my own business when all of a sudden... Oops wrong story. I had done some mylars with nitric acid about a week ago and thought that took quite a while to do. I did about 30 pieces. Plus I used @40 ml of acid. Had quite a few that didn't react at all. Mostly ones from laptops. So I set those aside for later. Put my copper pipe in to get the silver nitrate. All is good. Was wondering what to do about the ones that didn't react to the nitric. Burn them I thought. So I did. Got the films down to an ash that looked kind of like pumice. Burnt till there were no flames coming off them at all. Decided that while I was doing that I would throw the ones that did react in there too. Took my ashes and smooshed them all up to a powder, put that in a beaker and added some diluted nitric just to cover. Came back the next day, reaction was probably done in a few min's, filtered that solution into a dirty( my bad) beaker, HCL contamination, and ended up with a bunch of silver chloride. Did the lye/sugar thing, could have probably used salt I guess, and got a nice pile of silver nitrate to melt. Not sure how much I have yet, but am wondering if burning them first might be more economical as far as time and acid goes. Any thoughts would be appreciated.
Thanks,
Toby
 
Oh, Toby, there are a lot of problems in your process and your understanding.
ybotptl said:
I had done some mylars with nitric acid about a week ago and thought that took quite a while to do. I did about 30 pieces. Plus I used @40 ml of acid. Had quite a few that didn't react at all. Mostly ones from laptops. So I set those aside for later. Put my copper pipe in to get the silver nitrate. All is good.
40 ml. of acid was way too much for 30 mylars.

When you put the mylars in nitric acid the silver dissolves and becomes silver nitrate in solution. When you put a copper pipe in the solution, the copper dissolves and replace the silver because copper is more reactive than the silver. The silver "cements" out of the solution as metallic silver, not silver nitrate.

Was wondering what to do about the ones that didn't react to the nitric. Burn them I thought. So I did. Got the films down to an ash that looked kind of like pumice. Burnt till there were no flames coming off them at all. Decided that while I was doing that I would throw the ones that did react in there too.
I wouldn't have combined the relatively pure cemented silver with the more contaminated ash.

Took my ashes and smooshed them all up to a powder, put that in a beaker and added some diluted nitric just to cover. Came back the next day, reaction was probably done in a few min's, filtered that solution into a dirty( my bad) beaker, HCL contamination, and ended up with a bunch of silver chloride.
Yep, that was a mistake. You don't mention here whether you filtered to separate the silver chloride from any silver that may have remained in solution. Unless there was a lot of chloride contamination, you might still have some silver remaining in the solution as silver nitrate.

Did the lye/sugar thing, could have probably used salt I guess, and got a nice pile of silver nitrate to melt.
What? I understand if you used lye and sugar to convert the silver chloride to metallic silver, but you lost me on the rest of that. What do you mean by "could have probably used salt I guess"? Then you say you got a nice pile of silver nitrate to melt. If you used lye and sugar to convert silver chloride you ended up with finely divided metallic silver, not silver nitrate.

Not sure how much I have yet, but am wondering if burning them first might be more economical as far as time and acid goes. Any thoughts would be appreciated.
Mylars really have been discussed at length on the forum. If you do some searching you should find a better way. I haven't picked apart your post to be mean. I'm trying to help. When a lot of our members read a post like yours with so many errors they just don't bother to respond because they assume the member hasn't done anything to educate themselves. Other who want to help just don't know where to start to try to correct them, so they don't bother to respond either. Hopefully you'll be able to use some of the things I've mentioned to search out more information. If you need help on searching, take a look at my Tips for Navigating and Posting on the Forum thread.

Dave
 
Thanks for the reply. I don't mind the pick apart thing. I always remember offense is taken, not given. And I'm not offended. All part of the learning process. The "mylars that did react" part was the ones that turned black after the acid bath. I didn't put my cemented silver in with the ashes. I added some more HCL after seeing the milk form to be sure I got it all, or close to it anyways.
40 ml's was a guesstimate. I use a 3ml pipette and put quite a few in my baking dish, adding as I go to have enough to cover the films. Didn't want to put my rinse dish stuff in to compensate.
I guess anything that's not a little silver blob in my melt dish I call nitrate. My bad.
I did read quite a few posts on the subject. I think there were about 600 some. After awhile it gets somewhat frustrating. But anyways thanks for the reply Dave. I'll pay more attention next time. :)
 
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