Making Sodium Nitrate ?

[Noxx]

Hello guys,
I found a formula on the net about making Sodium Nitrate with Calcium Nitrate.
It goes as follow:

2NaHCO3 + Ca(NO3)2 => 2NaNO3 + CaCO3 + H20 + CO2

NaHCO3 is sodium bicarbonate which is easy to get. The only thing is, the solubility NaHCO3 is low... about 7 grams at 20°C...

I was just wondering if it would work or if I should look into something else...

Thanks

 

[aflacglobal]

Now that's interesting.

I would like to know that answer to.

:?:

 

[Lou]

It would work, but you'd get Ca(HCO3)2, there's no acid to make CO2.

Why not use sodium carbonate? It's much more soluble in water and gives insoluble calcium carbonate (chalk) as precipitate?

 

[Irons]

Also known as Washing Soda. It's available at the grocery store.

If you want to make Sodium Nitrate from Ammonium Nitrate, just react the Ammonium Nitrate with Sodium Hydroxide and boil off the Ammonia.

Both Sodium Hydroxide or Carbonate are likely to contain Sodium Chloride, so if you're trying to make a Chloride free Nitric Acid, it probably is pointless. Using the Calcium Hydroxide solves the problem because it is almost insoluble and any Chloride can be leached out if there is any at all.

The other choice is to man up an buy reagent grade chemicals.

The stingy man pays the most.

 

[Noxx]

I do not have any Ammonium Nitrate since it's restricted.

Alright, I will look into some washing soda The best solubility is at 40°C, you get about 50 grams in 100ml of water.

So the reaction will be this:

Na2CO3 + Ca(NO3)2 => 2NaNO3 + CaCO3 + H2O + CO2

I'll give it a try. 8)

Thanks guys.

 

[lazersteve]

Noxx,

Great idea to convert the Ca(NO3)2 into NaNO3! 8)

Here's a way to use your left overs from the original cold sodium nitrate nitric acid recipe and incorporate your Ca(NO3)2 idea into the loop.

This new method requires 170 gm of Sodium Nitrate to start the ball rolling, but thereafter you use your Calcium Nitrate along with the Sodium Sulfate left overs to reform the Sodium Nitrate, no Sodium Carbonate required. :wink:

Here goes:

Cold Nitric Acid Production using Ca(NO3)2, H2SO4, and NaNO3

Reaction #1

1) Bring 100 mL distilled H2O to a rolling boil (100 C)
2) Remove the H2O from the heat
3) Add 170 gm of NaNO3 into the 100 mL of hot distilled H2O with constant stirring until fully dissolved
4) Add 56 ml 98% H2SO4 in small portions to the niter solution with stirring, DO NOT let the solution boil
5) Let solution cool to room temperature (DO NOT skip this step or your reaction vessel may shatter!!)
6) Place reaction vessel into freezer or in a salted ice water bath until the solution temperature reaches -5 C
7) Let solution set for 30 minutes at -5 C
8} Pour or siphon off the liquid nitric acid while cold
9) Resultant salt is Na2SO4 and can be dried and used to convert Calcium Nitrate Ca(NO3)2 into more Sodium Nitrate (NaNO3) for next batch.

Reaction #2

Second batch using Ca(NO3)2 :

1) Heat 600 ml of distilled H2O to 33 C in a 2 Liter beaker (beaker #1)
2) Pour 300 mL of the warm water into a 1 Liter beaker (beaker #2)
3) Maintain the temperature of both beakers at 33 C while performing the next steps
4) Slowly add 183 grams of Ca(NO3)2 mono-hydrate to the warm water in beaker #2 with stirring until fully dissolved (adjust amount for higher hydrates)
5) Slowly add 142 grams of anhydrous Na2SO4 from step # 9 in reaction #1 (adjust amount for higher hydrates) to the warm water in beaker #1 with stirring until fully dissolved.
6) When all solids are dissolved add the contents of beaker #2 to beaker #1 with stirring maintaining the temperature at 33 C
7) After the two beakers contents have been combined cool beaker #1 until the temperature reaches 0 C for 30 minutes
8} Vaccuum filter off the liquid from the cold solution
9) The solid that remains in the filter is Calcium Sulfate and should weigh between 136 and 145 grams when dry
10) The liquid contains two moles of sodium nitrate (~170 grams)
11) Evaporate this liquid down to 350 mL
12) Filter out any solids that may have formed
13) Evaporate down to 175 mL
14) Use this hot liquid (95 C +) in reaction #1 starting at step #4 above to make more nitric acid. If you are going to store the Sodium Nitrate just evaporate it all the way down or keep the volume at ~350 mL until you are ready to concentrate it for use in reaction #1, step #4.

Here's your equations (excluding waters):

2NaNO3(aq) + H2SO4(l) --> 2HNO3(aq) + Na2SO4(s)

Ca(NO3)2(aq) + Na2SO4(aq) --> CaSO4(s) + 2 NaNO3(aq)

Let me know how it turns out as I just developed this reaction on paper for you this morning.

Good Luck,

Steve

 

[Irons]

Is much less hazardous than filtering Nitric.

If you can get Ammonium Nitrate, it can save a few steps by converting it directly with Sodium Hydroxide without first converting it to Calcium Nitrate.

It's good to know more than one way to skin a skunk.

 

[lazersteve]

Irons,

As you mentioned there are numerous ways to skin the skunk.

I think Noxx is already sitting on a big bag of Calcium Nitrate and wants to squeeze the nitric out if it.

I think he also has a good supply line of the Calcium Nitrate at a reasonable price.

By using his leftovers from the cold nitric acid reaction he can have a continual supply of nitric acid from Calcium Nitrate and conc. Sulfuric acid.

It would be nice to close the supply loop completely by getting the sulfate back out of the Calcium Sulfate and make more Sulfuric acid. :idea:

Something to ponder..

Steve

 

[Irons]

I think it would be easier to make a Sulfuric Acid plant. Anybody have any virgin auto catalyst?

Sulfur is very cheap.

S+O2=SO2

2SO2+O2=2SO3

SO3+H2O=H2SO4

 

[lazersteve]

Irons,

Here's a formula from wiki:

Sulfur dioxide is a by-product in the manufacture of cement: CaSiO3 and CaSO4 is heated with coke and sand in this process:

2 CaSO4(s) + 2SiO2(s) + C(s) → 2 CaSiO3(s) + 2 SO2(g) + CO2(g)


Could be a starting point with sand and carbon? You would even end up with cement. No telling how hot the above reaction has to get.

On second thought, Sulfuric acid is cheap. :wink:

Steve

 

[Irons]

Some day, you can figure out how to make Dry Wall and build yourself a house. :wink:

 

[Noxx]

Exactly... I still have the big bag of Calcium Nitrate
But how can I make it anhydrous ? Should I heat it in the over ? Anyone got an idea of the temp I can reach before it melts/decomposes ?

I'll give it a try in a few days and post the video.

Thanks guys

 

[Noxx]

Some day, you can figure out how to make Dry Wall and build yourself a house. :wink:

Are you talking about the Plaster of Paris ? :lol:
Very impossible to filter when in solution lol.

 

[Irons]

All you have to do is heat the Calcium Sulfate to drive off the water of hydration, grind it up and you have Plaster of Paris.

Now, there's a money maker for 'ya. :lol:

 

[Noxx]

Ok, I answered my question, Calcium Nitrate can be dried when heated from 130°C to 400°C. It decomposes at around 500°C

Then thoroughly dry the calcium nitrate at temperatures between 130 and 400 degrees centigrade. (400°C is grey glow, red glow is above 500°C) This is important as higher temperatures(red glow) will decompose the calcium nitrate, developing highly poisonous nitrogen dioxide.

http://www.sciencemadness.org/library/cano3.html

 

[lazersteve]

Noxx,

There's no need to dry the Ca(NO3)2, water isn't going to be a big factor in getting the sodium nitrate to form. Just be sure to adjust the amount of calcium nitrate you add to the mix by the increase in combined water weight (ie: 4 x 18 = 72 grams per mole more if you have Ca(NO3)2 * 4 H2O).

Steve

 

[Noxx]

I know Steve,
The only thing is, the composition of Calcium Nitrate is not constant. I mean, we don't know how much water is bond with it. Ca(NO3)2 * xH2O
I want to dehydrate it (only a few grams) to know the exact amount of water.

Thanks

 

[aflacglobal]

Some day, you can figure out how to make Dry Wall and build yourself a house. :wink:

Are you talking about the Plaster of Paris ? :lol:
Very impossible to filter when in solution lol.

It's that american humor again Noxx.

He meant if you were going to go to the trouble of trying to make every product instead of buying it why not just make your own drywall and build you a house at the same time.

 

[Lou]

I think it would be easier to make a Sulfuric Acid plant. Anybody have any virgin auto catalyst?

Sulfur is very cheap.

S+O2=SO2

2SO2+O2=2SO3

SO3+H2O=H2SO4

I've actually made sulfuric acid before from sulfur trioxide. It worked well, but there are many engineering and specialty problems, and SO3 is extremely dangerous.

Vanadium pentoxide with a small amount of potassium sulfate on a ceramic substrate is what's used industrially, it's also what I used. I still have the reaction tube I used. If you have a cheap source of SO2 and a tube furnace, you can make sulfuric acid of any concentration (and even oleums) quite simply. Burning sulfur to make your SO2 would be the best, as sulfur is really cheap! Still, it's very hazardous and really best left to industry.


As far as your reaction goes Steve, that won't work for sulfuric acid unless you further oxidize the SO2 gas to SO3 (+6), the acid anhydride of H2SO4. Doable with the above method. (edit*)

At really high temperatures, calcium sulfate decomposes into lime (CaO) and sulfur trioxide, but that's about 1300*C so it's thermally impractical.

edit: sorry Steve, sometimes I just get going . The contact process does work nicely if you want really high strength sulfuric acid.

 

[lazersteve]

As far as your reaction goes Steve, that won't work for sulfuric acid unless you further oxidize the SO2 gas to SO3 (+6), the acid anhydride of H2SO4.

The fact that you need SO3 to make sulfuric acid is a well known given. I was just pointing this out as a first step to using the raw materials available from the reaction at hand.

Kinda meant the whole sulfuric acid thing as a joke anyway...

On second thought, Sulfuric acid is cheap. :wink:

Steve