Sulphuric acid wet ashing VS Smelting

[Ayham Hafez]

Which one gives higher gold recovery from IC Chips, wet sulphuric acid ashing or smelting?

Regard silver with wet ashing,we can recover it by adding HCl to the sulphuric mud(after finish ashing and remove gold contents), then wait till all carbon settle down then smelt with soda ash and borax to get the silver, and regard fiber glass we can use HF to dissolve it after finishing wet ashing.

I know wet ashing is very dangerous but I just wonder if it has the higher gold recovery rate or smelting always beat?

 

[Shark]

Which one do the larger refineries use?

 

[nickvc]

Personally I’d rather have a lower return than mess with hot concentrated sulphuric.

 

[Yggdrasil]

Which one gives higher gold recovery from IC Chips, wet sulphuric acid ashing or smelting?

Regard silver with wet ashing,we can recover it by adding HCl to the sulphuric mud(after finish ashing and remove gold contents), then wait till all carbon settle down then smelt with soda ash and borax to get the silver, and regard fiber glass we can use HF to dissolve it after finishing wet ashing.

I know wet ashing is very dangerous but I just wonder if it has the higher gold recovery rate or smelting always beat?

We DO NOT recommend using wet ashing due to its dangers, and we certainly DO NOT recommend using HF since it is one of these extremely toxic compounds that can maim and kill you long time after exposure.

So you are talking about the two most dangerous procedures in chemistry in one paragraph.
Please stop this.
The large refineries grind and smelt, maybe without pyrolizing, but they are set up to handle the fumes in a responsible way.

 

[Ayham Hafez]

Which one do the larger refineries use?

Sure smelting, cause processing large quantities with acids are very toxic and expensive, I just ask which method gives higher yield.

 

[Ayham Hafez]

Personally I’d rather have a lower return than mess with hot concentrated sulphuric.

So that mean wet ashing gives higher yield, isn't it?

 

[Ayham Hafez]

We DO NOT recommend using wet ashing due to its dangers, and we certainly DO NOT recommend using HF since it is one of these extremely toxic compounds that can maim and kill you long time after exposure.

So you are talking about the two most dangerous procedures in chemistry in one paragraph.
Please stop this.
The large refineries grind and smelt, maybe without pyrolizing, but they are set up to handle the fumes in a responsible way.

I didn't say that wet ashing is good to go with, I explained that its very dangerous, but I asked to understand several points like how much we loose with smelting and the second point if there any gold lost during the wet ashing process. Cause many refiners use wet ashing to know the gold yield of ic chips (like fire assay).


You mentioned something new to me that large refineries don't pyrolyze, pyrolizing really took long time, can we just use wet scrubber with the furnace to handle the E-waste smoke? Wet scrubber I thought about is very simple since the furnace is small maybe just to handle crucible no 200, we can install ID fan above the furnace and at the end we push the air into barrel full of water that will eliminates smoke, also we can fire the gases from the water barrel so we will not get bad smell.

 

[Yggdrasil]

I didn't say that wet ashing is good to go with, I explained that its very dangerous, but I asked to understand several points like how much we loose with smelting and the second point if there any gold lost during the wet ashing process. Cause many refiners use wet ashing to know the gold yield of ic chips (like fire assay).


You mentioned something new to me that large refineries don't pyrolyze, pyrolizing really took long time, can we just use wet scrubber with the furnace to handle the E-waste smoke? Wet scrubber I thought about is very simple since the furnace is small maybe just to handle crucible no 200, we can install ID fan above the furnace and at the end we push the air into barrel full of water that will eliminates smoke, also we can fire the gases from the water barrel so we will not get bad smell.

Excuse me, read again.
Did I really say that they do not pyrolize?
You are jumping to conclusions mate.

 

[Yggdrasil]

So that mean wet ashing gives higher yield, isn't it?

No it do not mean that.
It means that even if it had higher yields he would not touch it.
The word of interest is if

 

[Ayham Hafez]

Excuse me, read again.
Did I really say that they do not pyrolize?
You are jumping to conclusions mate.

"The large refineries grind and smelt, maybe without pyrolizing"

What that's mean?

 

[Yggdrasil]

"The large refineries grind and smelt, maybe without pyrolizing"

What that's mean?

That means exactly as said:
Maybe they do not pyrolize.
Or with other words:
Maybe they pyrolize or maybe not.

Anyway it is moot since the scale we are talking about here will benefit from pyrolizing and incinerating before smelting.

 

[kurtak]

Which one gives higher gold recovery from IC Chips, wet sulphuric acid ashing or smelting?

Smelting

Or to put it another why - if the method you suggest worked better then smelting - then don't you think the BIG BOYS would be using that method - rather then smelting ???

Kurt

 

[Ayham Hafez]

Smelting

Or to put it another why - if the method you suggest worked better then smelting - then don't you think the BIG BOYS would be using that method - rather then smelting ???

Kurt

Really I hope smelting is the best cause I want to invest in 500 ampere copper cell and I was a bit confused that I will get higher yield or I will invest to get less.

 

[Shark]

Smelting

Or to put it another why - if the method you suggest worked better then smelting - then don't you think the BIG BOYS would be using that method - rather then smelting ???

Kurt

Even the big refineries use the term "melt loss" or "smelt loss". I would guess because at times acceptable loss is better than more dangerous, but I prefer to think because there is more profit in the method they choose. So very often "how do the big boys do it" is my first question when trying to decide how to process different items.