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From carbonate to nitrate


deadman

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I was wondering how to get strontium and barium nitrates from their carbonate forms. Would a double displacement of KNO3 work? If so how would one set up the apparatus for making it, and how could one seperate the very similiar white crystals? Any input would be appreciated.

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Just very simple. A carbonate is a base, Nitric acid is an acid. Putting a carbonate to nitric acid will result in a nitrate by an acid-base reaction. Like soda crystals. If you put this into nitric acid an acid base reaction will occur, there will form sodium nitrate. You can add a carbonate to the acid until it doesn't bubble anymore, after that you can boil out the water and save the nitrate crystals.

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Well, I've made Barium nitrate out of Barium carbonate using nitric acid.
You need a ratio of 1 part Bariumcarbonate, and 0.65 parts Nitric acid. But since my acid was 60 percent I used 1/1 ratio. (Other ratio's when you use Strontium carbonate, I haven't calculated that)

Wear gloves all the time when doing this, Barium nitrate is very toxic.

Just pour the HNO3 on the carbonate, and add some water so the acid reaches all carbonate. It will bubble like hell, so be aware. Stirr the stuff etc.. till there are no more bubbles.
The reaction here is:
2 HNO3 + BaCO3 --> Ba(NO3)2 + H2CO3
And since H2CO3 is not very stable, is decomposes forming H2O and CO2. (The bubbles! :) )

It's a good idea to neutralize the white slurry at this point. Don't use Sodium salts for neutralizing, since Sodium in your final product washes away all nice green colour.

Since you have used as less water as you could, not much nitrate will be dissolved. So just pour the entire mixture in a filter, and throw away the filtrate. (You can also boil it down to obtain just a little more nitrate)

Well, now you have your filter full of thick white stuff, this is very, very, very inpure Barium nitrate.
To make it pure, I just dissolved the stuff in as less water as I could use. At 80 degrees, about 30 grammes per 100ml of water dissolve. The carbonate doesn't dissolve.

Immediately pour this mixture into a filter, and this time throw away the residue in the filter.
Now let the filtrate cool down to about zero degrees centigrade, then just about 3 grammes of Barium nitrate dissolve per 100ml of water. So the most will turn to solid.

Well, filter it again, squeeze out the last water, and spread out to dry.
Heating it a little to make it dry faster is absolutely no problem here. I dried it on the radiator.

Now you should have obtained some clear white crystals, wich is quite pure Barium nitrate. The impurities will be mainly Barium sulfate, but that's no problem for pyro uses.

Well, I hope this will be of use to you.

Stijn

Edit: Yep, Nitroglycerin was faster than I was. :P

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You can also make it with Barium carbonate and NH4NO3 (AN). Put this in water, and you get a AN-solution. The barium carbonate won't solve much, maybe 1/10 of a gram. Did react with the AN to Bariumnitrate, CO2, H2 and I believe NH3. If this happens it starts to bubble very much. It is safer to cover it with a cloth, because the little parts of water that will be blown into the air contain Barium. It's poisonous, so it isn't good when you inhale this. With the cloth, it will stick to it so it won't get in the air. Of course it's good to heat this all up so the reaction will go faster. When the bubbling stops, there is no AN of barium carbonate any more, so you need to add it. Remember that you can't go on for a very long time, because if the Barium nitrate crystalizes, you can't separate it from the barium carbonate.

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It ís impossible to do it at home. I haven't researched methods, but I believe your teacher is right. Maybe a fractional recristallization or something, but I believe there's nothing else you can do, what's financially ok. I think it's better to look in the world/your region for fertiliser grade potassium nitrate.

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Thank you for all the input. Now seeing that I have to have nitric acid, is it worth it to make the nitric acid to make the nitrates? Are there good fountain and star comps that involve carbonates of strontia or baria, and still have a noticable color to them?

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For colors are chloride-anion salts the best agents, Like Julicher says above. Wikipedia.org says a lot about flame coloring compounds and combinations. Here are also nice pics. The chloride-ion appears to be the best anion for flame colouring, probably because it's a relatively big anion which doesn't color the flame and easily gives of the wavelength for colors we can see. I don't know if it has a higher rendement by taking a nitrate salt and use it as oxidizer and coloring agent such as chloride salt as coloring agent and a different oxidator.
It probably will change by which colour you want. Barium nitrate would do good. But for a copper blue colour will need an oxidator and copper chloride because copper nitrate ins't a that common oxidator, and I think it ins't that strong.

And ammonium nitrate will work also, bacause it's a acidic kation. I don't know in what it decomposes, it could be you need to purify the product because it's not pure enough or you want better colours.

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I also want to make Ba(NO3)2 with BaCO3 and NH4NO3 .

Only, How exactly must this be done ? If you boil your water, in the water alot of NH4NO3 can solve. Only how much BaCO3 do you need to add with , for example, 100ml water with 50g of NH4NO3 ?

I will put a piece of cloth on the ''stove'' (?) because of the Barium water.

Anyone ?

I expect better english from you Yellowcard. And allso you know the math related to this type of reaction. Julicher gave the complete equation (Reactievergelijking), so fill in the masses and get your calculator to work! T.

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Just put for example 1 KG of NH4HO3 in 1L of water. Put some Baria carbonate into the water, say 100 grams. Let it bubble for a while and when it stops bubbling, one of the two ingredients is out of resource (if you can say it like that). If you can see the Baria carbonate on the bottom, the NH4NO3 is out of resource. If there is no Baria carbonate on the bottom, there is no Baria carbonate anymore off course. Then add the stuff that is needed and it will start bubbling again. Don't puch it too far, because there is a limit the Baria nitrate can solve in the water. If it starts crystalizing, you can't separate it from the Baria carbonate. Then you need to add water an things like that, so that won't be that easy. And don't forget the cloth on the top.

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I don't mean to sound ungrateful, but distiling the HNO<sub>3</sub> is much to trouble for me at this time. Thank you for your replies.

I remember a post Gamekeeper had a while back and I want to say he used barium carbonate and ammonium nitrate to get barium nitrate. If a displacement is possible, or if I am remembering wrong please let me know either. Thanks all.

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Wow, I don't see how I missed those posts. I must have been out of it. Thanks a lot. Well since it is possible I'll have to give it a go. I won't ask for any more spoonfeeding as now I know it is possible.

BTW: prelast could have been said previous to my last or second to mylast. Technically it isn't a word in the english language but I understood what you meant.

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