Fiberglass removing

[Sy-Spark]

I want to strip gold from RF connectors using cyanide, but the thick plated area which is pin of the connector usually coated with fiberglass, burning the connectors will make carbon insulation layer and its not a clean process, any idea for removing the fiberglass from it?

 

[Yggdrasil]

I want to strip gold from RF connectors using cyanide, but the thick plated area which is pin of the connector usually coated with fiberglass, burning the connectors will make carbon insulation layer and its not a clean process, any idea for removing the fiberglass from it?

Is it not possible to dismantle it?

 

[Sy-Spark]

Is it not possible to dismantle it?

No, it's waste of time cause it's mechanically pressed not threaded, also am talking about tens of kilograms from this material.

In past I was using Nitric-sulphuric leach to get full gold yield, but I stopped dealing with large acids quantities, then I processed them by smelting and copper cell but zinc vapors during smelting really a big issue so I decided to only deal with them using cyanide method. The different between cyanide method and the full gold yield is about 25% because the thick plating is on the coated pin inside the connector.

 

[Yggdrasil]

I want to strip gold from RF connectors using cyanide, but the thick plated area which is pin of the connector usually coated with fiberglass, burning the connectors will make carbon insulation layer and its not a clean process, any idea for removing the fiberglass from it?

Fiber glass are not soluble in any acceptable acids.
Neither are epoxy.
Pyrolyzing and ashing will be the only option besides cracking them open manually.

 

[Sy-Spark]

Fiber glass are not soluble in any acceptable acids.
Neither are epoxy.
Pyrolyzing and ashing will be the only option besides cracking them open manually.

Do you think burning them then leaching them in NaOH will remove any carbon insulation on plated copper so I can use cyanide?

 

[Yggdrasil]

Do you think burning them then leaching them in NaOH will remove any carbon insulation on plated copper so I can use cyanide?

I'd test with one at a time to see what works.
But I see no upside with NaOH, it will not touch the Carbon.

 

[haveagojoe]

I want to strip gold from RF connectors using cyanide, but the thick plated area which is pin of the connector usually coated with fiberglass, burning the connectors will make carbon insulation layer and its not a clean process, any idea for removing the fiberglass from it?

It's not fibreglass it's PTFE, there are very few things which will dissolve it, and high temperature and pressure are needed for dissolution.

Best option in my opinion is to push them out with a press and custom jig. Any drill press will work, just use a flat-ended rod or an upside-down drill bit. And no power of course. Then cut the PTFE insulator to remove the central pin.

I do the bodies of similar gold-plated SMA connectors in Copper Chloride to recover the gold plating as foils, it works and is a lot safer than cyanide. It's the one situation I add Hydrogen Peroxide as it helps to release the foils before the substrate is attacked too much. I also use a lot of agitation to free the plating.

 

[haveagojoe]

Burning PTFE releases dangerous vapors which can cause Polymer Fume Fever ("Teflon flu") and potentially acute lung injury

https://en.wikipedia.org/wiki/Polymer_fume_fever

 

[Sy-Spark]

It's not fibreglass it's PTFE, there are very few things which will dissolve it, and high temperature and pressure are needed for dissolution.

Best option in my opinion is to push them out with a press and custom jig. Any drill press will work, just use a flat-ended rod or an upside-down drill bit. And no power of course. Then cut the PTFE insulator to remove the central pin.

I do the bodies of similar gold-plated SMA connectors in Copper Chloride to recover the gold plating as foils, it works and is a lot safer than cyanide. It's the one situation I add Hydrogen Peroxide as it helps to release the foils before the substrate is attacked too much. I also use a lot of agitation to free the plating.

I stopped using AP since long time cause I believe that with AP I will spent lot of time and miss some gold.

They are thousands of connectors so I don't think it's a good idea to mechanically remove the insulator.


PTFE decomposes very quickly in pyrolisis reactor, I read that benzene can remove carbon from metals surface easily, I'm planning to make a small test to see if leaching the dirty connectors in benzene will solve the issue.

 

[BGDOCK]

For what it’s worth those can be pushed out easily with a punch, a pair of Klien’s and a vice in a minute.

 

[haveagojoe]

They are thousands of connectors so I don't think it's a good idea to mechanically remove the insulator.

With a press it will go faster than you might think. You can make a jig with a square hole which they fit into exactly, to hold them perfectly straight and in the exact right position when you press down, that way you can process hundreds per hour and your process will be much cleaner and safer.

You're right, AP is not the most efficient way to retrieve the gold from these, but it's the safest and easiest. I just leave them to work while I do something else. It doesn't work well on the pins though.

If you want speed, a sulfuric electrolysis cell would work well on these, both the bodies and the pins.

 

[haveagojoe]

Also you could consider thiosulfate alkaline leaching, which is a safer alternative to cyanide.

https://www.mdpi.com/2075-4701/7/6/222

 

[Shark]

Small arbor press with a hole drilled in a metal plate will pop those centers out in a hurry.