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lazersteve said:
It will work for any base metal that dissolves in nitric acid.

The numbers given are for copper based scrap, adjust according to base metal type molar mass relative to copper and it's respective nitrate compound formula.

Steve

Do you think that I could use the acid-peroxide method instead of nitric acid or sulfuric acid and nitrates? I have some hydrogen peroxide somewhere, it is in the concentration for medical applications I guess.
 
lazersteve said:
Acid Peroxide works for copper based scrap, and not other base metals.

Steve

What is the proper ratio of the 35% sulfuric acid to sodium nitrate for the regular version of poor mans nitric acid?
 
With 98% sulfuric acid the required volume 57 mL per 170 g or NaNO3.

Since you want to know what volume of 35% H2SO4 to use simply do the math:

35% / 98% = 0.357

57 mL / 0.357 = ~ 160 mL 35% H2SO4

or

160 mL H2SO4 / 170 g NaNO3 = 0.94 mL of 35% sulfuric acid per 1 g of nitrate.

Don't forget the water need for the reaction.

Steve
 
lazersteve said:
With 98% sulfuric acid the required volume 57 mL per 170 g or NaNO3.

Since you want to know what volume of 35% H2SO4 to use simply do the math:

35% / 98% = 0.357

57 mL / 0.357 = ~ 160 mL 35% H2SO4

or

160 mL H2SO4 / 170 g NaNO3 = 0.94 mL of 35% sulfuric acid per 1 g of nitrate.

Don't forget the water need for the reaction.

Steve

How much H2SO4 and sodium nitrate should I use for each gram of scrap? Do I add water if I am using dilute acid?
 
The first pages mentions 50 grams of copper. does this mean that I will need to use half a liter of acid and multiple kg of nitrates just to dissolve a pound of copper? I only have 370g of NaNO3 and about a liter of 98% HSO4. Also, my largest beaker only holds 1 liter. If I cannot get a hold of sodium nitrate, should I just use the acid peroxide method instead?
 
The math for dissolving copper with nitric has been shown in several places on the forum.

Search my posts for 'copper sodium nitrate' (without the quotes) and you will see the math for nitrate and copper.

It's a lot of nitrate per pound of metal.

Steve
 
lazersteve said:
The math for dissolving copper with nitric has been shown in several places on the forum.

Search my posts for 'copper sodium nitrate' (without the quotes) and you will see the math for nitrate and copper.

It's a lot of nitrate per pound of metal.

Steve

Thanks, I suppose these things are easier to understand when put into terms of basic chemistry and equations, I remember doing stoichiometry like this in high school and college. It seems as if all of the methods of base metal dissolution that requires nitrates is impractical for me (I don't want to have to repeat the process 10+ times in a 1 liter beaker to process a pound of scrap).
 
infinatesorrow said:
now im assuming anhydrous sodium bi-sulfate would be just your basic pool treatment since its without water in salt form?

Not necessarily so, plenty of salts contain water in their crystalline structure. The only way to know for sure is to dehydrate it by heating to the point where is no longer gives off water. If your salt appears to melt t 58.5C you have the type with water in it's structure. If it melts at 315C it's the anhydrous type.

Steve
 
I thought I'd bump this topic, as I was in Lowe's recently & they are changing vendors for pool supplies. Therefore, they are "Clearance"-ing some of the chemicals we use, including sodium bisulfate, used in the "Dry Poor Man's Nitric" described here.

The large container of 95% sodium bisulfate, "Ph Decreaser", was less than $4 US.
EDIT: clarity/accuracy
 

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