Advice on AR

[timlatham2020]

I am using poor mans AR which is desolving my gold nicely but I am a bit confused after seeing many varying methods of denoxing the AR, should i be meausuring for PH 3 after adding sulfamic acid or is it the case to keep adding untill it stops fizzing because of the inability to measure ph because even though the Sulfamic has neutralized the nitrates the hydrochloric will always make it show ph 0.00, very confused, thanks in advance for your help. Its just one refiner said he looks for ph 3, am i doing something wrong?

 

[Yggdrasil]

I am using poor mans AR which is desolving my gold nicely but I am a bit confused after seeing many varying methods of denoxing the AR, should i be meausuring for PH 3 after adding sulfamic acid or is it the case to keep adding untill it stops fizzing because of the inability to measure ph because even though the Sulfamic has neutralized the nitrates the hydrochloric will always make it show ph 0.00, very confused, thanks in advance for your help. Its just one refiner said he looks for ph 3, am i doing something wrong?

You are not neutralising the acid, you are decomposing/destroying Nitrates and its components. Sulfamic acid is fine for that, but it needs to be done hot 90c or around that.

 

[eaglekeeper]

because even though the Sulfamic has neutralized the nitrates the hydrochloric will always make it show ph 0.00

If you plan on using SMB to drop the gold, it will need to remain low in Ph for it to work.

 

[timlatham2020]

How do i lower the ph? By using sulfamic at 90c?

 

[Yggdrasil]

How do i lower the ph? By using sulfamic at 90c?

I'm sorry about it but I failed to notice you were new.
What you do is seal up all your chemicals and put them safely away from kids and animals.
Then you start to study so you do not hurt yourself or anyone around you.

I suggest starting with safety and waste management, then start reading Hokes book.

When you feel ready, come back here and lay out your plan, then we will help adjust it if needed.


We ask our new members to do 3 things.
1. Read C.M. Hokes book on refining jewelers scrap, it gives an easy introduction to the most important chemistry regarding refining.
It is free here on the forum: Screen Readable Copy of Hoke's Book
2. Then read the safety section of the forum: Safety
3. And then read about "Dealing with waste" in the forum: Dealing with Waste

Suggested reading: The Library

https://goldrefiningforum.com/threads/gold-refining-forum-rules.31182/

 

[kurtak]

Its just one refiner said he looks for ph 3, am i doing something wrong?

I don't know where you got that advice but it is not good advice --- as Ph goes up so does the possibility of dropping base metal hydroxides along with your gold

If your Ph is above 1 add HCl to bring your Ph down to at least 1 (or 0)

Kurt

 

[kurtak]

I should clarify (my last post) if you are dropping your gold with SMB you want your Ph low (0 - 1) it is the reaction of the low Ph acid with the SMB that creates the SO2 gas that drops your gold

If you are using oxalic acid to drop your gold you want to do a Ph up adjustment

Kurt

 

[Shark]

One day I am going to try oxalic acid.