How much Sulfamic acid is needed?

[bhilton]

Hello,

I plan to use 10ml of nitric acid for AR, but I only estimate ill have 0.2 to 0.3 grams of gold. That means I’ll have to use enough Sulfamic acid to denox 9.7ml of nitric acid.

Can anyone guide me on how much Sulfamic acid crystals to use?

 

[Yggdrasil]

Hello,

I plan to use 10ml of nitric acid for AR, but I only estimate ill have 0.2 to 0.3 grams of gold. That means I’ll have to use enough Sulfamic acid to denox 9.7ml of nitric acid.

Can anyone guide me on how much Sulfamic acid crystals to use?

Why do you plan to use that much Nitric?

 

[bhilton]

Why do you plan to use that much Nitric?

I have a few paper towels and filters I want to smother.

I understand they will break down a little bit, but a bit more solution will be easier to manage than a tiny amount.

Unless there is another better method.

I could burn them all up in a pan in my wood stove, that seems like it could be a bit more of a mess to deal with. I am open to hearing any suggestions!

 

[Yggdrasil]

I have a few paper towels and filters I want to smother.

I understand they will break down a little bit, but a bit more solution will be easier to manage than a tiny amount.

Unless there is another better method.

I could burn them all up in a pan in my wood stove, that seems like it could be a bit more of a mess to deal with. I am open to hearing any suggestions!

Put them aside until you have enough.
You could also moist them with HCl and spray SMB on them in the mean time.

 

[bhilton]

Put them aside until you have enough.
You could also moist them with HCl and spray SMB on them in the mean time.

Why spray smb on them in advance?

 

[Yggdrasil]

Why spray smb on them in advance?

The Gold Chloride will turn into Gold and it may minimize losses.

 

[bhilton]

The Gold Chloride will turn into Gold and it may minimize losses.

Ok I understand, cool!

I will do that and get them decomposing.

Aside from that, is there a guide on how much sulfamic acid to use if I have an estimated idea of how much extra nitric is in solution?

Don’t worry, I will always try to avoid using excess nitric!

 

[Yggdrasil]

Ok I understand, cool!

I will do that and get them decomposing.

Aside from that, is there a guide on how much sulfamic acid to use if I have an estimated idea of how much extra nitric is in solution?

Don’t worry, I will always try to avoid using excess nitric!

No, just enough.
It will foam considerably if excess are present so you will know.

 

[bhilton]

No, just enough.
It will foam considerably if excess are present so you will know.

Ok and is there a suggested temp to bring AR up to before adding sulfamic acid?

I searched the forum, no headline seemed to mention anything about the proper temp.

 

[Yggdrasil]

Ok and is there a suggested temp to bring AR up to before adding sulfamic acid?

I searched the forum, no headline seemed to mention anything about the proper temp.

If you have searched the forum you would have found it!
But anything from 80C and up, but not boiling, we never boil pregnant solutions.

 

[kurtak]

but I only estimate ill have 0.2 to 0.3 grams of gold.

I have a few paper towels and filters I want to smother.

Put them aside until you have enough.

As yaggdrasil said - save you filters &/or paper towels (as well as cotton swabs used for stannous testing) up until you have enough to make it worth while chasing (like at least 1 or 2 grams)

chasing a couple tenths of a gram you will be LUCKY to recover that couple tenths of a gram - the reason you lost it in the first place (to being tied up in the filters/towels)

When you have a 5 gallon bucket (or 2) full of this kind of material it will be worth chasing & we can revisit methods of how to recover something worth chasing

Kurt

 

[bhilton]

As yaggdrasil said - save you filters &/or paper towels (as well as cotton swabs used for stannous testing) up until you have enough to make it worth while chasing (like at least 1 or 2 grams)

chasing a couple tenths of a gram you will be LUCKY to recover that couple tenths of a gram - the reason you lost it in the first place (to being tied up in the filters/towels)

When you have a 5 gallon bucket (or 2) full of this kind of material it will be worth chasing & we can revisit methods of how to recover something worth chasing

Kurt

 

[bhilton]

Well it is hard to guess how much gold ill have from the jar of mixed fingers. Maybe 0.5g.

I went ahead and after first filter here it is.

Next ill heat it up and slowly sprinkle sulfamic and filter and then smb when it cools down.

 

[bhilton]

I brought the AR up to a slow boil, reduced the heat and added sulfamic acid slowly until fizzing stopped.

Solution changed from yellow to orange like.

Then I let it cool down and there was some precipitate at the bottom.

Very fine dark brown colour. Attached a picture.

I filtered it out with a cotton ball.

Then I put in smb and no reaction.

Maybe I still have nitric?

Here are my amounts used:

-250ml hcl
-Dropped in 2.5ml 58% nitric acid at 0.5 increments.
-Heated to a slow boil, turned heat down
-Added slowly, a total of 7.9g of sulfamic acid, fizzing stopped
-Let it cool
-Observed very fine dark brown sediment
-Filtered it with a cotton ball
-Added 2.5 teaspoons of smb in small increments

No reaction from the smb.

Any ideas?

 

[Yggdrasil]

I brought the AR up to a slow boil, reduced the heat and added sulfamic acid slowly until fizzing stopped.

Solution changed from yellow to orange like.

Then I let it cool down and there was some precipitate at the bottom.

Very fine dark brown colour. Attached a picture.

I filtered it out with a cotton ball.

Then I put in smb and no reaction.

Maybe I still have nitric?

Here are my amounts used:

-250ml hcl
-Dropped in 2.5ml 58% nitric acid at 0.5 increments.
-Heated to a slow boil, turned heat down
-Added slowly, a total of 7.9g of sulfamic acid, fizzing stopped
-Let it cool
-Observed very fine dark brown sediment
-Filtered it with a cotton ball
-Added 2.5 teaspoons of smb in small increments

No reaction from the smb.

Any ideas?

Are you sure it is Sulfamic acid and not SMB?

 

[Shark]

I brought the AR up to a slow boil, reduced the heat and added sulfamic acid slowly until fizzing stopped.

Solution changed from yellow to orange like.

Then I let it cool down and there was some precipitate at the bottom.

Very fine dark brown colour. Attached a picture.

I filtered it out with a cotton ball.

Then I put in smb and no reaction.

Maybe I still have nitric?

Here are my amounts used:

-250ml hcl
-Dropped in 2.5ml 58% nitric acid at 0.5 increments.
-Heated to a slow boil, turned heat down
-Added slowly, a total of 7.9g of sulfamic acid, fizzing stopped
-Let it cool
-Observed very fine dark brown sediment
-Filtered it with a cotton ball
-Added 2.5 teaspoons of smb in small increments

No reaction from the smb.

Any ideas?

From the picture it looks like your gold dropped out.

 

[bhilton]

Are you sure it is Sulfamic acid and not SMB?

Yes

From the picture it looks like your gold dropped out.

Shark, I thought it looked that way too.

I kept it all in the filter with cotton ball so I am currently running it through another refining.

 

[Yggdrasil]

Do you need to deNOx your solution?
How much Nitric do you use?

 

[bhilton]

Yes I do. This time I used 60ml of hcl and 0.4ml of nitric (58%).

I just brought it up to temp and sprinkled little bits of Sulfamic acid, looks good, this time nothing dropped!

It's cooling down now, I'll bring the solution below room temp with an ice cube and try a tiny bit of smb and let ya know how it goes.

 

[Yggdrasil]

Yes I do. This time I used 60ml of hcl and 0.4ml of nitric (58%).

I just brought it up to temp and sprinkled little bits of Sulfamic acid, looks good, this time nothing dropped!

It's cooling down now, I'll bring the solution below room temp with an ice cube and try a tiny bit of smb and let ya know how it goes.

What and how much did you dissolve