max6333 Posted January 29, 2015 Posted January 29, 2015 Question #1When I was boiling down a solution of ammonium nitrate my plan was to wait untill crystals start forming,even though noone ever did that in the guides now I think I know why they only boil it down partially.While I was boling it, it turned orange.Thats when I stopped . I took it off the stove and crystals started forming instantly (means it was real close to start crystalizing out on the stove).When it crystalized the crystals were orange too , what I want to know now is why it happened and how to stop it, also does it harm the efficency of the ammonium nitrate Question number #2 Can I just evaporate the ammonium nitrate solution or will it not work because ammonium nitrate ishygroscopic
BurritoBandito Posted January 29, 2015 Posted January 29, 2015 Are you sure what you have is ammonium nitrate? If so, what were you boiling it in? I ask because AN will attack some metals, like copper for example. You should use Pyrex if available. You will probably find it difficult to evaporate the water away, because as you said AN is very hygroscopic to the point of being deliquescent.
max6333 Posted January 29, 2015 Author Posted January 29, 2015 I am boiling it in pyrex infact, also I vaporized a small ammount and it turned out white, also the fertilizer i got it from is named kAN
GalFisk Posted January 29, 2015 Posted January 29, 2015 Nitrogen dioxide is strongly orange, so maybe your ammonium nitrate has begun to decompose.It's ten times a soluble in boiling water as freezing water, so you'll get 90% of your stuff out if you cool it. Maybe more if it can be crashed out with alcohol (I don't know if it can; potassium nitrate can).Not sure what to do about the orange stuff though (whether it's NO2 or something else).
FlaMtnBkr Posted January 29, 2015 Posted January 29, 2015 (edited) If you have it in the right conditions you can dry it. But it will quickly pull water back in. Even in humid Florida I can soak a piece of newspaper in saturated AN solution and dry it in the sun in about 20 minutes. I think low heat and some time will dry it. I have no idea about the orange. I've been drying AN and accidentally got it too hot to the point a good portion melted and never had it change color. Not sure what the melting point of AN is but probably a lot more than your saturated solution. I bet it's an impurity but that's a WAG. Edit: in case you are wondering why I soaked newspaper in it, it makes a pretty good smoke bomb. Soak it, dry it, and roll it up into a cylinder. Light the center and it will start spraying out dense white smoke. Edited January 29, 2015 by FlaMtnBkr
max6333 Posted January 29, 2015 Author Posted January 29, 2015 Yes it might be the nitrogen dioxide, because when I did it on the stove it went just a bit orange and on some fast water boiler it turned full orange, also i see the hygroscopisness because after some time white bubles appear on it (i guess thats the moisture that got in it).Also how do I know that i boiled it down good enough?(when the max solubility on 100 C has been achieved)
max6333 Posted January 29, 2015 Author Posted January 29, 2015 One more thing, the solution turns orange too not just the crystals
pyrojig Posted January 29, 2015 Posted January 29, 2015 Sounds like another chem in the fert causing this. Possibly a coating .
GalFisk Posted January 29, 2015 Posted January 29, 2015 Solubility table form Wikipedia: 118 g/100 ml (0 °C)150 g/100 ml (20 °C)297 g/100 ml (40 °C)410 g/100 ml (60 °C)576 g/100 ml (80 °C)1024 g/100 ml (100 °C)
max6333 Posted January 29, 2015 Author Posted January 29, 2015 (edited) Yeah, but its kinda hard to dissolve 1000 grams of the fertilizer in 100 ml and its only 30% so i Would have to dissolve 3kg of the fertilzer Edited January 29, 2015 by max6333
GalFisk Posted January 30, 2015 Posted January 30, 2015 Yes, but you can use the table to know roughly when the max solubility at 100C has been achieved, by knowing how much NH4NO3 you put in and measuring how much liquid you have left during boiling.I think the problem is that as the liquid gets more concentrated the boiling point rises, until it's above the temperature where the NH4NO3 starts to decompose. So a thermometer is probably more useful than a volume measurement, for knowing when it's time to stop. I think (but I have no experience with this) that you can get rid of the orange color in your crystals by drying them, since NO2 is volatile. Try it and see. If the color is not from NO2, I don't know.
max6333 Posted January 30, 2015 Author Posted January 30, 2015 I'm getting it from kan fertzilizer, also yes it stopped being orange after 3 days but now its all hygroscopy
Mumbles Posted January 30, 2015 Posted January 30, 2015 KAN also has calcium nitrate in it. That is far more hygroscopic in my experience than AN. You'll have to get rid of that completely before it becomes manageable most likely.
FlaMtnBkr Posted January 30, 2015 Posted January 30, 2015 AN is deliquescent and in Florida humidity a spilt prill will be a puddle in just a couple hours. It is a pain to work with. At least if you are trying to get it to burn. How are u determining that the fertilizer is 30% AN?
Jakenbake Posted January 30, 2015 Posted January 30, 2015 (edited) I think he may be working with prilled KAN (CAN). Washing the calcium out with water and then boiling down the finished product. Lots of work and i was never able to end up with a moisture free product. Are you using the AN for targets? Edited January 31, 2015 by Jakenbake
Blackthumb Posted January 31, 2015 Posted January 31, 2015 (edited) My An is prilled and works great for targets...the others are correct in that you have to remove the calcium to get it to function properly...quite bothersome Fertilizer Grade 34-0-0 Edited January 31, 2015 by Blackthumb
schroedinger Posted January 31, 2015 Posted January 31, 2015 A couple things you maybe missed:Like allready mentioned how pure is your AN, only on + insoluble crap or soluble stuff? If it is the 2nd put it away.If you have the first you can easly boil down the solution. Here comes the part where you have to decide white or no white AN (the brown tinting is normal and doesn't harm the effect of the AN). If you boil down your solution you will never get any crystals of AN formed, the reason is that the solubility of the AN rapidly increases with heat and after some time the solution inverts. From AN in water to water in AN.For white AN just keep boiling until you reach 140-150ºC. Pour into a pan break up the cooled An and dry in an oven at 150 ºCIf you are fine with the brown dicoloring keep boiling until youreach 170ºC. Then pour the AN onto a drying pan. This is pure liquid AN. I would recommend the first way sincs it leaves you with a much easier to handle product then the second (dry and allready broken up, bars of an aren't the easiest thing to break up again, while keeping them dry) one.
max6333 Posted January 31, 2015 Author Posted January 31, 2015 maybe its only 13% percent an...and the other 13% is calcium nitarate
max6333 Posted January 31, 2015 Author Posted January 31, 2015 (edited) I let a part evaporate and I can see the ammonium nitrate and also something that totaly hygroscoped out.Maybe the hygroscoped thing is the calcium nitrate, also how do i remove the calcium nitrate? Edited January 31, 2015 by max6333
max6333 Posted January 31, 2015 Author Posted January 31, 2015 http://www.nitrogen.hu/nat/index.php?option=com_content&view=category&layout=blog&id=4&Itemid=235&lang=en There is no calcium nitrate just calcium carbonate, says it all on this site.I have a plan now , the stuff that I let to evaporate i will dissolve in very little boiling water and then i will put it in the fridge, but i only got like 10 grams there so it will have to dissolve in 1 ml of water... wich seems impossible but the wiki says its possible
Mumbles Posted January 31, 2015 Posted January 31, 2015 Boiling the solution will make much more calcium and magnesium nitrates. I think you'd be better off dissolving in water, filtering, and then boiling it down or evaporating. If you try to extract with hot or boiling water, I think you'll have more trouble than it's worth.
max6333 Posted February 1, 2015 Author Posted February 1, 2015 I dissolved some in almost boiling water, didnt crystalize at all in the freezer, but I evaporated it in 2 hours and it turned out fine, didnt hygroscope out
mormanman Posted February 14, 2016 Posted February 14, 2016 Boiling the solution will make much more calcium and magnesium nitrates. I think you'd be better off dissolving in water, filtering, and then boiling it down or evaporating. If you try to extract with hot or boiling water, I think you'll have more trouble than it's worth. Mumbles, are you saying to clean the AN follow those steps? I have some farm grade stuff that I would like to clean to make targets with. But I don't know the percentage of the AN.I've always been worried about the hydroscopic properties.Please forgive my ignorance.thanks
schroedinger Posted February 14, 2016 Posted February 14, 2016 Yes you only need to put the fertilizer in a bucket, add water and wait until the temperature is at room temperature again and that most of the debris has setled. Now you pour the liquor into a filter and boil the water of. Either wait until you reach 120ºC, let cool down and dry at 150ºC in an oven or heat the solution up to 165ºC and pour into a tray. Both will give you ammonia nitrate dry and pure enough for most applications. The second method however yield often a brown product due to organic debris left in the solution and getting oxidized.
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