I'm sorry, I'm not at my post.

[TK421]

Hello all!

I've been lurking here for a while, and finally getting around to processing a bunch of electronic scrap I've been collecting for 20-ish years. Probably about time I started participating in this forum instead of watching through the windows, right?

I'm completely new to refining. I know a bit about chemistry, but "Just enough to get myself in trouble", as my high school chemistry teacher used to say about me. To that end, I've realized I'm using WAY too much nitric acid in my AR, and my precipitations are as barren as my local California precipitation.

I have a copy of Hoke's book, but to be honest, I find it somewhat difficult to read. Victorian English is not my first language.

Cheers!

 

[orvi]

Collecting scrap for 20 years... That would produce a nice pile
For first, it is the best to stick with proven and tested ways how to do it, like ones in Tutorial section of forum. And start to use your own modified procedures when you dig deeper and build confidence in what you are doing - and more importantly when you completely understand chemistry behind. It can get dangerous, messy and expensive

Wishing luck with your venture.
Stay safe
Orvi

 

[TK421]

Thank you!

Chemistry has been a hobby of mine for 15 years or so. I used to buy a lot of stuff at auction, especially Silicon Valley "junk", and I've recently decided to get rid of a lot of it. Most of it is pre-1995 or so, and a lot of it is 1960s and 1970s, mostly purchased in my search for the Holy Grail of CPU collecting - the Intel 4004. So far, in 20+ year of searching, I've found one in the wild. Sure, I can go on eBay and buy one for hundreds (or thousands) of dollars, but what's the fun in that?

Along the way, I've picked up tons of old test equipment, various abandoned projects from the Stanford Research Institute, and even a Cray supercomputer.

Unfortunately, I'm moving shortly, so I'm trying to figure out a way to put everything I have safely on hold. I have a lot of gold already dissolved, and I'm worried about it off-gassing if I put it in storage for a few weeks. I'm trying to either precipitate as much as I can now, or somehow stabilize it in a small area.

 

[orvi]

Thank you!

Chemistry has been a hobby of mine for 15 years or so. I used to buy a lot of stuff at auction, especially Silicon Valley "junk", and I've recently decided to get rid of a lot of it. Most of it is pre-1995 or so, and a lot of it is 1960s and 1970s, mostly purchased in my search for the Holy Grail of CPU collecting - the Intel 4004. So far, in 20+ year of searching, I've found one in the wild. Sure, I can go on eBay and buy one for hundreds (or thousands) of dollars, but what's the fun in that?

Along the way, I've picked up tons of old test equipment, various abandoned projects from the Stanford Research Institute, and even a Cray supercomputer.

Unfortunately, I'm moving shortly, so I'm trying to figure out a way to put everything I have safely on hold. I have a lot of gold already dissolved, and I'm worried about it off-gassing if I put it in storage for a few weeks. I'm trying to either precipitate as much as I can now, or somehow stabilize it in a small area.

Gold won´t go anywhere when dissolved and nothing is added to the solution. Also it won´t dissolve if anything capable of dissolving it is added.

 

[nickvc]

If you wish to reduce the volume of value bearing solutions you can always cement the values out using copper save the powder and refine again later, be sure to treat any waste properly before disposing of it.

 

[cosmetal]

Howdy, neighbor!

Peace and health,
James

 

[TK421]

Howdy, neighbor!

Hey neighbor!

If you wish to reduce the volume of value bearing solutions you can always cement the values out using copper save the powder and refine again later, be sure to treat any waste properly before disposing of it.

Honestly, I'm not sure how to do that. Does there exist a list of metals or metal salts in order of their...prevalence? affinity?...to being forced out of solution, or forcing other metals out of solution?

I'd rather keep the solutions in liquid form, simply because they're already liquids, and I can store them until I get settled in to my new place in a couple weeks. My biggest concern was them off-gassing corrosive gasses, or bursting their storage containers. I'd also rather not buy a lot more reagents, though I think I'll be setting up a Birkeland-Eyde reactor once I move. Nitric acid is the only reagent that really costs me anything.

 

[FrugalRefiner]

Honestly, I'm not sure how to do that. Does there exist a list of metals or metal salts in order of their...prevalence? affinity?...to being forced out of solution, or forcing other metals out of solution?

See When In Doubt, Cement It Out.

Dave

 

[markscomp]

Thought I'd share a pic of the Intel c4004 - took me few years to find this

 

[butcher]

Do some study on the reactivity series of metals, the solubility of metals, and oxidation and reduction potentials of metals and their chemical reactions, see dealing with waste in the safety section.

Copper will displace any valuable metal dissolved in solutions as ions, the copper will dissolve and trade places with the more valuable metals, the copper losing electrons to become ions dissolved in the solution, the valuable metals gaining those electrons to become atoms with a full shell of electrons these atoms join together to form elemental metal powders, the copper is oxidized (lose of electrons) the valuable metals silver gold PGM's will be reduced ( a gain of electrons) to become elemental metals, leaving the metals which are more reactive than copper behind in the solution.

The valuable metal powders can be dried for transport, saving, further processing, or whatever, normally they are refined further for a higher purity or to separate the valuable metals from each other for a higher value product...

You are then left with toxic hazardous waste, adding iron will displace copper from the solution with a few other toxic metals see the reactivity series of metals that can be dried. The copper can be reused.

Now raising the pH of this solution to pH 11 will precipitate iron and many of the other base metals from this salt solution as insoluble hydroxides which can be removed from the solution and dried.

Some metals will redissolve at this high alkalinity or pH, so bringing the pH back down ( using a little acid) to a neutral pH 7 will precipitate more of those toxic base metals that dissolve in excess base or alkaline solution (the amphoteric metals), these hydroxides can be dried with the others and disposed of.

This leaves you with a saltwater solution that is less toxic (having the more toxic metal ions or salts removed), which can then be disposed of, (although you do not necessarily need to, I dry my solutions to crystal salts before disposal).

 

[TK421]

See When In Doubt, Cement It Out.

Dave

Thank you! Part of my problem is that I'm getting a gray precipitate when trying to drop with SMB, and I started with whole metals (plated contacts, PCBs, and such), so I have a lot of copper, tin, lead, iron, and God-knows-what in solution. I need to take a step back and not touch anything until I learn more.

Thought I'd share a pic of the Intel c4004 - took me few years to find this

Yours is nicer than mine! I have a purple/gray all-ceramic one without the gold heat spreader. I actually found it on a fluke - I responded to a Craigslist ad for a medical bed being given away by a retired doctor, and as we got to talking, he told me he had a bunch of other equipment he was looking to "dump". One item was a large scintillation detector he used to analyze iodine in thyroid patients, and out of it I got an i4004, a couple i4002 (320 bit) RAM ICs, and a large scintillation detector tube. I'm pretty sure it uses a sodium iodide tube, so not exactly rare, but it's the only one I've ever had in my hands.

Do some study on the reactivity series of metals, the solubility of metals, and oxidation and reduction potentials of metals and their chemical reactions, see dealing with waste in the safety section.
...
This leaves you with a saltwater solution that is less toxic (having the more toxic metal ions or salts removed), which can then be disposed of, (although you do not necessarily need to, I dry my solutions to crystal salts before disposal).

Thank you! I have a fume hood on wheels that's in storage right now, and I think I'm going to just put everything in there as is. I'm moving this weekend, and things got kinda crazy. Short version of the story: my landlord lost the house I am/was renting from him to foreclosure, and didn't tell me about it. He withheld all the notices his bank sent, so I don't have a lot of time to move, much less work with this gold project right now. I'll have things settled in a couple weeks.

I kinda brain-farted, too - I couldn't remember the term "reactivity series" last night, and I was wondering if it would be the same thing. It's been a while since I did anything with that - probably 10+ years.

 

[VK3NHL]

Hello all!

I've been lurking here for a while, and finally getting around to processing a bunch of electronic scrap I've been collecting for 20-ish years. Probably about time I started participating in this forum instead of watching through the windows, right?

I'm completely new to refining. I know a bit about chemistry, but "Just enough to get myself in trouble", as my high school chemistry teacher used to say about me. To that end, I've realized I'm using WAY too much nitric acid in my AR, and my precipitations are as barren as my local California precipitation.

I have a copy of Hoke's book, but to be honest, I find it somewhat difficult to read. Victorian English is not my first language.

Cheers!

Read Hokes Book then read it again.
Chemistry is like cooking, just don’t lick the spoon.
Some of Hokes safety practices are certainly dated, but once you have read it twice; Read it again.. good luck & welcome..

 

[TK421]

Read Hoke's Book, then read it again.

I just finished printing it out! I'm very thankful for the efforts of the people who put it together in a PDF. I have trouble reading for a long time on a screen, so having it in print is huge for me.

Chemistry is like cooking, just don’t lick the spoon.

Ironically, right after high school I got into a culinary academy. I still love cooking, but the professional culinary world (full of high pressure and drugs) was not for me. However, one of the first things we learned was that cooking is not an exact science - everything is done to taste, because ingredients vary from lot to lot, fruit to fruit, pepper to pepper. The jalapeños you buy today might be a fraction as spicy as the ones you bought last week. Bread ingredients, however, are weighed to the gram.

Cheers!