Refining Sodium Nitrite

Topic created by Anon
on Wed, 15 Feb 2023 at 20:25

Anon said on Wed, 15 Feb 2023 at 20:25...

I am going to throw out my experience with cleaning out sodium nitrite melting it down.

Sodium nitrite and sodium nitrate have two different melting temps and this can be used to separate the two.

This can be done on a ceramic bowl on a gas stove burner. Pick a bowl with a large flat bottom to reduce the effects of temperature gradients.

I purchased some sodium nitrite and doped my sodium nitrate with it to see how hard it is to get with the temperature band of the two. It is doable but you have to work a little harder. It is easy to melt both and then stir it as the temp drops.

You want your burner to just be hot enough to melt the sodium nitrite. If you do it too fast, you'll burn both and your product will turn tan or brown. It is not hard to prevent this from happening. You just have to go slow. Like a few hours for 2 lbs.

When you are done melting both turn off the heat and start stirring it. You will get build up around the outer edge of your bowl. This will be sodium nitrite mixed with sodium nitrate. I would just toss it. When the main portion gets below the melting point of the solution will turn foggy quickly with crystals. Slightly turn on your burner to just prevent the temperature from dropping quickly. The sodium nitrate will float and form a layer on top if you give a chance.

Heat up a spoon on a burner and scoop this out. You have to heat up the spoon because otherwise everything will harden on your cold spoon, including sodium nitrite.

You'll end up toss some sodium nitrite out at the expense of sodium nitrate. This isn't that hard if you are patient.

The alternative of trying to stay between the temp band of the two is doable and I was able to hold a temp where the granuals of nitrate added wouldn't melt. I think this is doable but you need to have a mixer or mix it a lot or do something to prevent hot spots. I think someone could workout something to do this and they would just have to fine tune or tweak their setup unit it just consistently fell into the right range.

When you cool it down, pour it into a bowl or plate you have pre-heated to prevent thermal stresses from cracking it. The result should have a yellowish white color with some white stuff that might be anti-caking agent. Sodium nitrate I believe is white and not off white yellowish.

It is very doable to not burn it. You can use a thermometer but in my opinion you are better to just watch the transitions. Did it all melt when you heated it slowly? When you turned off the heat did you watch for the transition of when the sodium nitrate cooled enough to form crystals and fog up or look like slush in the solution? Go slow and you won't burn it

Aside from that, melting down the powder into a disc I think helps prevent decay due to exposure to air or humidity.

Anon said on Wed, 15 Feb 2023 at 20:35...

I will throw this out their. The first time I did this it turned out my clumped up sodium nitrite was very clean and I didn't know it. It might be worthwhile to buy a little bit of sodium nitrate to sanity check yourself by putting in a few granuals and seeing that they didn't melt if run the temp close to the melting point of sodium nitrite. That will show you that you have fairly clean material because the granule of sodium nitrate that didn't melt would be proof that any sodium nitrate that is in the solution should have solidified at that temp.

To help get the temp down and and near the melting point of sodium nitrite, consider adding more sodium nitrite to the mix. Add cold sodium nitrite to the mix brings the temp down and visual any unmelted sodium nitrite is below the melting temp. When you get very close to the melting temp, a thin layer forms immediately when exposed to air.

Anon said on Wed, 15 Feb 2023 at 21:04...

Furthermore, something I have been doing after melting the sodium nitrite into rocks is just dropping them undisolved into the water and alcohol mixture that acid drips into. I was before this experimenting with slow dropping both sodium nitrite in solution and acid into a alcohol water mixture and found that it helped to significantly reduce any bubbling. I think this idea of doing things at increasingly lower temps stems from the fact that you have sodium nitrite and acid reacting too quickly because the concentrations are too high. Trying to get ridiculously low temps I think is people trying to get around the fact that they are adding acid to a solution that is saturate with sodium nitrite.

One side note of this, this last time put a rock of sodium nitrite in the solution, I put it inside of a ziploc bag with a bunch of small holes put into it. I did this to try to reduce the dissolving rate of the rock. I think it did this but what I found was that almost all the alkyl nitrite that was create flowed up to the surface inside of the bag. I think someone could setup something where they position a rock of sodium nitrite by something to either collect the product continuously or to shield the result from acid. I think someone could play games because they can kind of control where the alkyl nitrite is made and will flow upward.

Mikhail said on Thu, 16 Feb 2023 at 23:59...

It is not that simple. Try this out with calibrated electric furnace controller and slowly raise to midpoint between melting points of NaNO2 and NaNO3. You will see no collection of NaNO3 on side of crucible. A little might float the top for which is very difficult to skim. If you try to skim it, you get some, but the rest drops down to never rise back to surface again. It looks like semen washed with water, small, clumpy bits about. If you let crucible for several hours, NaO forms, and now you have to deal with strong base. NaO looks similar to unskimmed NaNO3 suspended.

Barrier idea is interesting. You could try simple baffle where acid is injected instead.

Anon said on Mon, 20 Feb 2023 at 16:34...

Yes, it look like what you say. I think is doable. I have done it faster than I did earlier in the post without burning it. I think you can use this method to clean it up but you just live with the fact that you are also throwing away sodium nitrite. I think it probably has more application in preserving it by reducing exposure to oxygen and humidity. Though, I question why you wouldn't just buy more than waste your time trying to scavenge old stuff. Like what is your time worth.

I have gotten barrier thing to work with putting the sodium nitrite in a tea seeper and a glass liquor sample bottle. The Tea seeper works if you don't bump it and cause it to diffuse out of control.. This was in a alcohol and acid mixture diluted with a lot of water. It slows down some when some slime builds up on the sodium nitrite to slow down it diffusion. The tea seeper I think is a bit too porous to slow down the diffusion enough.

With the sample liquor bottle, you see small stream of tiny bubbles and alkyl nitrite as alcohol and water diffuses in the bottle and reacts with the sodium nitrite.

The result was a little weak in both but more than some purchased stuff. I had to use more water than I would like to get it so the container was submerged. With the small liquor bottle I need like 3 inches of depth. I think I should buy glass beads or something to bury containers so I don't need so much water. I think that this method could work and be very repeatable to just use natural diffusion to release sodium nitrite,acid, or both into the solution. I think it would require some trial and error but the end result is that you have simplified the process down to filling some containers with cold water, acid, and sodium nitrite and just putting them into the refrigerator for a few hours. I think natural diffusion is enough to run the process out slowly. I think someone would just have to play with the process until their containers had enough of an opening to maintain the process without letting it run away.

This is a side comment, I am kind of wondering if excess alcohol shouldn't be used. If you dilute the alcohol with two much water, you end up with a weak result, assumely because your nitrous acid decayed before reacting with alcohol. I am kind of wandering if you are better off running high alcohol to get more nitric acid to react with alcohol and hen after you separate the alcohol from the batch, add it to a small container with distilled water and then add a little acid and sodium nitrite to react with the remaining alcohol in the popper. Like you aren't trying to get the vat clean of alcohol but just want the product free. I used to try to neutralize my popper with sodium nitrite rather than sodium carbonate and when I did that, I always had no alcohol left. I think your commercial poppers all run the alcohol high to produce more product, which is why you can always tell in the product what alcohol they used. JJ has triple distilled gold or whatever I think to clean out their product because they had loose process. The only product that I have smelled that was very clean was double scorpio white gold and I still think they clean it at the end. I think this distilling though would be unnecessary if the process was tight but I think that means you have lower yields and have to use more expensive reactants.

Anon said on Mon, 20 Feb 2023 at 22:09...

Mikhail,

I ran it again with twice as much alcohol as needed with the teapot. The teapot is too pourace. It pushed bent the lid open on my vessel and leaked some NO. I replaced the lid and let it run out. Then I poured off the top layer into a jar.

It was high as expected in alcohol so I poured some cold water, some acid, and a bit more sodium nitrite to clean out the alcohol in the popper. It came out clean after letting it run out. I suspect in general it would be better to run with a high alcohol content and then clean out the popper at the end then try to distill it or hope you get the ratios that match the grade of your reactants.

Anon said on Tue, 21 Feb 2023 at 22:42...

Mikhail,

I tried acid diffusion out of some salt and pepper shakers. It looked promising at first but I think that was just due convention. Just due to diffusion, especially when the mixture is cold, it takes a long time for a sulfuric solution to diffuse through water. I think you need a stirrer or something to assist convection if you want to diffuse a liquid through a liquid. Maybe, a smaller jar. I diffused 90 ml of 40% sulfuric acid through about 400 ml of acid, alcohol, with sodium nitrite rocks at the bottom. It was slow even at room temp. Maybe you could make this work with a smaller jar that has a wide bottom and narrow top.

Nitritespecialist said on Sun, 5 Mar 2023 at 19:09...

After 10 years, I have found that the alcohol purity is far more important than the SN purity. As such, I only recommend buying factory sealed alcohols from TCI or Sigma. I also recommend using the alcohols ASAP as they degrade quickly as more and more air replaces the contents.

You cannot always tell the BASE alcohol used because it could be degraded or mixed with other chemicals/alcohols. I have purchased second hand amyl alcohol that smelled like Frito Feet. Clearly, it had degraded. Sigma's 95% Butyl Nitrite degraded into a very sweet banana scent, which is not how I would describe butanol. Pure BN gives a room a very VERY distinctive deodorized locker room scent....If it doesn't provide that odor, it's either not BN or not very pure.