1rst time reverse electroplating

[Goldmember123]

Hello and Thank you all who answered my last questions ! I did get some useful info but im i need to put my situation into better Perspective ! Ok i have like 11 pounds of Gold plated conductor pins mixed together from all kinds of different electronic devices ! I have 10 pounds of gold plated fingers from motherboards just the fingers no other parts of the boards ! I Understand the Safety measures i must take when using and or mixing any kinds of Acids and i dont have a background in Chemistry but i do understand Do's and Dont's and i understand using all safety measures and i know how to operate in a Cognitive Step by step Process ! Can Someone Please Explain the Whole process of using Aqua Regia from start to finnish from even collecting it out of the solution ? Please ! ?

 

[butcher]

I would start with C.M. Hoke's book it will give you the basic principles, She explained the chemistry in layman's terms.

The safety section is helpful in learning the dangers and how to protect yourself and others.

The guide to the forum and the general reaction list will help you in beginning to learn many of the workarounds we use that may not be covered in C.M. Hoke's book.

The search engine is helpful in finding information on different processes and the problems involved...

Different materials may need different recovery methods, or even different pretreatments or requirements to prepare the scrap for a recovery process. Many times there is more than one method that you can use to come to the same conclusion in recovery or a refining process.

Spending time studying will help you gain an understanding of the different processes, doing the experiments in Hoke's book will be very helpful in understanding the chemical reactions of the metals your studying and give you the basics for troubleshooting problems as they arise.



With working with electronic scrap many times there is no need to use aqua regia, as the gold is fine or in powdered form and can easily be dissolved without nitric and having to deal with removing it before precipitating the gold from solution.

 

[Martijn]

We now have two threads... can one of the admins delete the other one? Its a bit confusing. Here are the replies from the other one:
Dave's comments:

Welcome to the forum.

Please don't double post. I deleted your other post.

I would not use a car battery as your power supply. A car battery charger has a limited amperage and safety circuitry that will shut it down in case of a short circuit. A car battery does not.

The gold does not collect on the lead bar. It ends up as a very fine sediment at the bottom of the dish.

Make sure the basket doesn't block the path from your scrap to the lead bar.

Be sure you understand the hazards of working with concentrated sulfuric acid. An accident can be life altering.

Dave

My reply in the other thread:

Welcome to the forum.
Dangers of using concentrated sulphuric acid:
It burns through anything organic. Fast!! Clothing, skin, bone etc. When hot, its even more aggressive.

Keep water far away from this stripping cell. One drop in your acid and you are in big trouble.
No spray bottle anywhere near it.
Keep the temperature low by limiting the current through the cell to a few amps max. I have experienced very little fumes coming off when kept below 40 degr. Celcius @2Amps max. But i have always done it inside a fume hood.

Using a face mask with cartridges, we're not to fond of that here. The need for personal protective gear like that is a sign of poor preventive safety measures and poor work practices. Dont mean to offend you.
PPG like safety glasses, gloves, a face shield or a partially lowered front window on a fume hood are not a bad idea.
Getting the acid on your skin and face is your biggest concern. It wil scar you for life at least.

I measure temperature with an infra red temp. meter. No drops and spills caused by using a glass thermometer.

When tapping the deplated items out of the basket in a DRY container, avoid a spring action with the basket. This can catapult drops of acid back towards you.
Keep a bucket with water and baking soda in it to wash any accidental drops as fast as possible.

Don't use thick clumsy gloves, but nitril gloves instead. Throw them away if there is some acid on them and put on new ones. You should not get any acid on your gloves if you work safe.

Start small. Get some experience and confidence using this process before going bigger.

Dont rinse the basket between refills, same effect as with a drop of water. If you have rinsed it, to store the basket after using it, use a hot air gun to comletely dry it before storing it.

To get the last bits of plated gold off, i used a twisted bunch of copper wires and connected to the + to make contact on different places in the basket on the items.
When the current drops, the gold is deplated. Place and hold the rod on another spot, and find the leftover spots of gold by watching the currrent go up to the limit setting again.

The most dangerous part is pouring the acid with the slimes in water to dilute it. Add ice to the BIG container of water if you want to do that.
You can also let it settle for a couple of days and carefully siphon off the clear acid from top and only dilute the slimes on the bottom. The siphoned off acid can go straight back into the cell and is not wasted.
Store the cell with a lid on it to keep moisture from the air away from the acid.
This can cause the sulphuric to lower in concentration by absorbing moisture from the air, in which copper becomes more soluble because the acid gets diluted with water, and slowly eating away your basket.

And when pouring the acid off, make sure the outside of your beaker and gloves are free of any sulphuric! It gets pretty slippery when wet and using gloves. Almost dropped a glass beaker onto anther once while spraying the last bits out

Be very carefull. Be safe.
Martijn.

@Goldmember123: since your PM contained no private info, i will share it and my reply here:

Hello sir, thank you for the info ! About what you said about the gold not collecting to the lead bar i saw a video one time where this guy got the gold to collect to his lead bar some how ! Is that even a real process ? or is the whole thing bogus ?

I did not say that. That was Dave. Not sure if some gold gets trapped on the lead anode.
Just rinse and brush off the lead anode into your slime wash water and recover the gold.
You can better ask these questions in the thread you started so others can learn from it. Sharing is what were all about.
And dont double post. It makes a mess of this forum.
Martijn.