Non-Chemical Hydrochloric acid boil question

[Dougplogan]

I've been collecting gold foils from AP solution. I've just been using a coffee filter to retrieve foils then rinsed well with distilled water. After the filter dries out I stuff it down in a mason jar. Foils come from many different kinds of escrap. My question is when I go to boil in hydrochloric acid to further clean them will all these coffee filters break up and desolve? Should I add a few drops of sulphuric acid mid boil? Also originally I'd planned on using a beaker or mason jar for this. Just putting sand in a hot plate and sitting the jar on top. Ive not really gotten to this point yet so not sure if a stainless steel pot can be used if the nonstick coating effects things.

 

[FrugalRefiner]

I wouldn't recommend mason jars for dissolving gold. A beaker would be better.

A sand bath spreads heat, but you still need a secondary containment vessel in case your beaker breaks.

I don't understand the comment about stainless steel with a non-stick coating. HCl will attack stainless.

Dave

 

[Dougplogan]

I wouldn't recommend mason jars for dissolving gold. A beaker would be better.

A sand bath spreads heat, but you still need a secondary containment vessel in case your beaker breaks.

I don't understand the comment about stainless steel with a non-stick coating. HCl will attack stainless.

Dave

I was wondering about stainless. I only mentioned it because in reading other posts I've come across pictures people have added were they were using metal pot doing a hydrochloric boil. It had pictures of foils before during and after. And the during was a metal pot. I do have beakers but the mason jars seem like they'd be less likely to break during heating. I've only processed once with ar. I learned then why the beaker is needed. When gold precipitated it stuck to the sides all around the jar.

 

[Yggdrasil]

Hydrochloric acid will most likely dissolve your Stainless.
Nitric will not.
Generally speaking.
There are special classes of stainless, but 304 316 which is what you will find in ordinary stores will dissolve in HCl.

 

[Dougplogan]

Hydrochloric acid will most likely dissolve your Stainless.
Nitric will not.
Generally speaking.
There are special classes of stainless, but 304 316 which is what you will find in ordinary stores will dissolve in HCl.

If I can find the post again I'll share it here to show what I was asking. I guess if I'm going to go buy something I was hoping to get to use it for multiple things. My thoughts were a metal pan I would be able to use for inceneration purposes as well. Out of curiosity the white ceramic baking dishes every one uses what are they called again. I'm guessing the glass baking dishes aren't ideal.

 

[Dougplogan]

The filters I have are full of gold foils and a blackish powder. They don't seem very clean that's why I was thinking a hydrochloric acid boil. Plus it's several filters from different stuff. One is phron old cell phone boards with gold plating. That one has lots of green flakes from the boards breaking up. Is adding a few ml of sulfuric acid while doing the boil a good idea to help clean stuff up? One thing I am sure of is that I have avoided tin. Everything is processed in HCl before ap solution till all evidence of soldering is gone.

 

[cejohnsonsr1]

The issue with Mason jars is the relatively rapid change in temperature from hot to not hot. They’ll break. Good quality beakers are designed specifically to not break under these circumstances. Don’t use any kind of metal container for these processes. Steel is at the very top of the list of the series of reactivity. Anything you dissolve in it will cement out upon it. Stick with the high quality beakers mentioned previously. If you’re certain that all other metals have been removed, you have options as to how you dissolve the gold. AR, using small, incremental doses of Nitric, on heat, will dissolve the filter papers. Any trash or solids get filtered out after all the gold is dissolved. This will produce the least amount of waste, but requires the most care and vigilance while processing and is a bit more expensive. You can also dissolve with AP or AB but it takes a lot longer and generates considerably more waste and it won’t dissolve the filter papers, so you have to be very thorough when rinsing, which generates even more waste. No matter which method you choose to dissolve, filtering the pregnant solution and precipitation will all work the same way. Good luck with it and Merry Christmas!

 

[butcher]

A pyro ceramic dish can be used for heating or as a catch basin with or without your sand bath.

 

[Dougplogan]

The issue with Mason jars is the relatively rapid change in temperature from hot to not hot. They’ll break. Good quality beakers are designed specifically to not break under these circumstances. Don’t use any kind of metal container for these processes. Steel is at the very top of the list of the series of reactivity. Anything you dissolve in it will cement out upon it. Stick with the high quality beakers mentioned previously. If you’re certain that all other metals have been removed, you have options as to how you dissolve the gold. AR, using small, incremental doses of Nitric, on heat, will dissolve the filter papers. Any trash or solids get filtered out after all the gold is dissolved. This will produce the least amount of waste, but requires the most care and vigilance while processing and is a bit more expensive. You can also dissolve with AP or AB but it takes a lot longer and generates considerably more waste and it won’t dissolve the filter papers, so you have to be very thorough when rinsing, which generates even more waste. No matter which method you choose to dissolve, filtering the pregnant solution and precipitation will all work the same way. Good luck with it and Merry Christmas!

I've been using AP. Though I guess it was only AP the first time. Now I just mix some old AP with HCl and let it sit for a while. It worked faster when it was warmer outside but no real hurry I suppose. Thanks for the heads up on the mason jar. I'd have learned that one the hard way for sure. What I have now Is a dry mason jar full of coffee filters full of gold foils. All the foils came from AP solutions. I don't want to add them to ar just yet. Plus that many coffee filters I'd prefer to keep out of the refining process when time comes. Will they be digested if I do an HCl boil. I know I need to anyways to insure the foils are clean. I do have a small amount of sulfuric acid. I just read conflicting information on adding it to hcl

 

[FrugalRefiner]

See What will hold up? Pyroceram.

Dave

 

[Yggdrasil]

I've been using AP. Though I guess it was only AP the first time. Now I just mix some old AP with HCl and let it sit for a while. It worked faster when it was warmer outside but no real hurry I suppose. Thanks for the heads up on the mason jar. I'd have learned that one the hard way for sure. What I have now Is a dry mason jar full of coffee filters full of gold foils. All the foils came from AP solutions. I don't want to add them to ar just yet. Plus that many coffee filters I'd prefer to keep out of the refining process when time comes. Will they be digested if I do an HCl boil. I know I need to anyways to insure the foils are clean. I do have a small amount of sulfuric acid. I just read conflicting information on adding it to hcl

Adding sulfuric will give you a big mess.
Use AR, it will dissolve the filters when hot.
Or any other method to dissolve the gold, but this involves many thorough washes and as a result more waste.

 

[BLACKESTFOOT]

The glass catch dish is called
Corningware.

 

[snail]

Key to identifying pyroceram from more modern substitutes is the part number.
The part number on pyroceram begins with a P prefix.

 

[Dougplogan]

Adding sulfuric will give you a big mess.
Use AR, it will dissolve the filters when hot.
Or any other method to dissolve the gold, but this involves many thorough washes and as a result more waste.

So basically it would be better idea to go to ar then wash at this point? I think I get adding sulfuric to a hydrochloric boil is a bad idea. At that point I'd have a problem filtering from there. The foils for the most part are fairly clean in the coffee filters except for ones that came from gold plated cell phone boards. And those just have green circuit board flakes were the boards started flaking.

 

[Yggdrasil]

The filters can go to AR after you have made sure the copper chloride is dissolved.
No point in letting easy dissolved thrash follow your gold.

 

[VK3NHL]

A pyro ceramic dish can be used for heating or as a catch basin with or without your sand bath.

AND is an absolute must!
Common name ‘Corning Ware’

 

[Dougplogan]

The filters can go to AR after you have made sure the copper chloride is dissolved.
No point in letting easy dissolved thrash follow your gold.

Even if it's 20 or more coffee filters. As far as gold content I'd be surprised if it's 5 grams. That many filters will still desolve in such a small amount of acid? I suppose I could burn off the filters. It maybe the easiest way to get everything down to smaller size

 

[Yggdrasil]

Gold like carbon and vice versa.
In that case you should make sure it is completely incinerated.
No black specks left.

 

[Dougplogan]

Gold like carbon and vice versa.
In that case you should make sure it is completely incinerated.
No black specks left.

I'd be incenerating then washing with hydrochloric

 

[Yggdrasil]

What will you accomplish by that?
The only problem by incinerated filters is that the ash may be hard to filter.
Dissolving copper chloride and tin is best done before incineration, in my mind at least.