Help with Sodium Nitrate mixture

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MR.ED

Member
Joined
Dec 30, 2008
Messages
22
Location
washington
Hi , I am having a major problem Lazer steves Nitric acid procedure. Here is how i do it ,.its for a 5x batch of lazer steves recipe
Bring 500 ml of dstilled water to a boil
I start adding 25ml of sodium nitrate at a time until all 800grams of sodium nitrate is boiling in solution .
It looks like it is all mixed in solution and i even boil for a additional 10 minutes to make sure. (I do notice a yellow film ring around the glass jar though)
I then take sodium nitrate solution off heater until solution has stopped boiling. (About for 1 minute)
I then start adding the 280 ml of sulfuric acid around 30 ml at a time (AND THIS IS WHERE I GET A BIG PROBLEM!!)
Every time i add some of the Sulfuric acid (rooto drain cleaner from lowes) the sodium nitrate solution turns into a white foamy , cottage cheese looking material. Why could this be happening??
And when i add the whole 280 ml of sulfuric acid the whole batch turns into a white foamy , cottage cheese mixture. then i leave it for a day and at no time does this white material break down into solution
 
MR.ED said:
Hi , I am having a major problem Lazer steves Nitric acid procedure. Here is how i do it ,.its for a 5x batch of lazer steves recipe
Bring 500 ml of dstilled water to a boil
I start adding 25ml of sodium nitrate at a time until all 800grams of sodium nitrate is boiling in solution .
It looks like it is all mixed in solution and i even boil for a additional 10 minutes to make sure. (I do notice a yellow film ring around the glass jar though)
I then take sodium nitrate solution off heater until solution has stopped boiling. (About for 1 minute)
I then start adding the 280 ml of sulfuric acid around 30 ml at a time (AND THIS IS WHERE I GET A BIG PROBLEM!!)
Every time i add some of the Sulfuric acid (rooto drain cleaner from lowes) the sodium nitrate solution turns into a white foamy , cottage cheese looking material. Why could this be happening??
And when i add the whole 280 ml of sulfuric acid the whole batch turns into a white foamy , cottage cheese mixture. then i leave it for a day and at no time does this white material break down into solution

The salts that you see are from the reaction, they will not go back into solution. Put your solution on ice or in the freezer once soution has cooled you can filter it.

I have found it is best for me to do the following:

I bring my water just below boiling and add about 1/8 of the sodium nitrate, that disolves and I add another 1/8 this will mostly disolve. I let this stand for a few minutes to let the water heat up a little bit more from the cooling of adding the nitrate. I follow this till all nitrate is disolved and then lower the heat. If you continue to boil from this point crystals will come out of solution. I let this cool down to about 90 C and then add the sulfuric. You might need to add water during the operation if you get to the point no more of the crystals stop disolving.
 
There are two kinds of Rooto drain opener:

1) The potassium hydroxide version and

2) The sulfuric acid version.

Which one did you buy?

The sulfuric acid one states it's concentrated sulfuric acid on the label and comes in a bottle packed in a plastic bag. The hydroxide version is not used in this process.

Steve
 
I bought the good stuff that is in the plastic bag that says sulfuric acid

Did you also see my question when i add the sulfuric acid to the mixture??
Thanks for the help ed
 
MR.ED said:
I bought the good stuff that is in the plastic bag that says sulfuric acid

Did you also see my question when i add the sulfuric acid to the mixture??
Thanks for the help ed

Those are the salts developing, throw them out once you are completed with the process.
 
The ratio of NH4 to Na is

18 / 23 = 0.78

So use 3/4 the amount of NH4NO3 as NaNO3.

Substitutions in the reaction are not going to work the same due to the solubility of the resulting sulfate salt. One of the key features of the cold nitric reaction is the unique solubility curve of Na2SO4.

(NH4)2SO4 = 70.4 g per 100 mL H2O @ 0C

Na2SO4 = 4.7 g per 100 mL H2O @ 0C

Not only is the sodium sulfate less soluble at 0C and below, it's solubility sharply drops (by 10 fold) between 32C and 0C:

Na2SO4_sol.jpg


This unique property of sodium sulfate makes it well suited for the cold reaction. The very low solubility ensures the sulfate precipitates to form the nitric acid.

Steve
 
MR.ED,

You should try using 600 grams of sodium nitrate with 200ml of sulphuric acid for every 500ml of water. I bet you will be happier with your end result.
 

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