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Author: Subject: Urea
artemov
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[*] posted on 27-1-2021 at 03:33


Quote: Originally posted by macckone  
artemov,
Crashing out of water using alcohol as a cosolvent is useful for a number of purifications.
The basic procedure is to dissolve a urea/ammonium sulfate mixture in minimal water.
Then add about 4 times as much dry alcohol as solution.
The ammonium sulfate will form fine crystals free from urea.

Ammonium sulfate is only slightly soluble in 80% alcohol while urea is very soluble.

The procedure I actually use involves dissolving it in significantly more water than necessary and evaporating most of it off, then adding alcohol.

Since the stuff I get is fertilizer grade, I can filter off insoluble impurities with the excess water.
Then get nice pure crystals that I can rinse with alcohol to get rid of any remaining urea.

The alcohol can be redistilled and reused.
The remaining urea can be recrystalized from dry alcohol.

The mix I get is about 90% ammonium sulfate and 10% urea.



Oooooo ... thanks!
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Hey Buddy
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[*] posted on 3-3-2021 at 14:48


I've isolated melamine and some lesser condensed ureas. I'm enroute to s heptazines but I'm slow. Intent now is to experiment with oxidation of melamine prior to moving on to melem and melon. For those intent is oxidation and then complexing with metals and nitroso complex. For now melamine. MDO is 2,4,6-triamino-1,3,5-triazine-1,3-dioxide. It has a meager det rate but is a good starting point enroute to MDONA. In reference to RSC Adv., 2021, 11, 288–295 | 289, they are using hydrogen peroxide/TFA for oxidation. Is there an equivalent of TFA that is less expensive? I have read that melamine adducts readily with many things including both H2SO4 and H2O2. Does it make any sense to attempt oxidation with Melamine/h2o2, urea/h202? Or is there an alternative? Ozonolysis in solvent? I'd rather avoid TFA.

[Edited on 3-3-2021 by Hey Buddy]

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^MDO/MDONA/MDOP

[Edited on 3-3-2021 by Hey Buddy]
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draculic acid69
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[*] posted on 4-3-2021 at 00:30


Quote: Originally posted by Fyndium  
Quote: Originally posted by j_sum1  
An awful lot would depend on what you were trying to accomplish.


Truly, apart from ammonia generation, hydrazine and urea nitrate, are there any collection of useful purposes for urea?

Alkali Cyanate production and therefore cyanide
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Fyndium
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[*] posted on 4-3-2021 at 03:02


That obvious one, of course, which I have done already with success.

Other one is urea hydrogen peroxide adduct, which can come in handy. I was thinkering could it be extracted from sodium percarbonate, but the solubilities limit the recovery. Possibly using a solvent that dissolves urea and hydrogen peroxide but not sodium carbonate either as is or by adding it to water solution to crash out the carbonate?
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[*] posted on 6-3-2021 at 19:17


Quote: Originally posted by draculic acid69  
Quote: Originally posted by Fyndium  
Quote: Originally posted by j_sum1  
An awful lot would depend on what you were trying to accomplish.


Truly, apart from ammonia generation, hydrazine and urea nitrate, are there any collection of useful purposes for urea?

Alkali Cyanate production and therefore cyanide


I'm not even any good at chemistry and I can clearly see that urea is significant. I've been reading of it's application in industries and chemistry for about 4 months now and there is no end in sight. It is wonderful. In energetics, I view it as a tree diagram, with incredible fractals of potential. The condensation products alone are each fascinating with wide and diverse application. Urea can be used directly as a fertilizer, biuret on the other hand inhibits plant function until it decomps into urea, where it then becomes a fertilizer. It continues on like this. Melmine and melem, melon are really exciting because there is relatively little exploration in that area, its recent interest is due to carbon nitride and boron nitrides, which are easily produced from melemine. Melamine is incredible and is clearly underutilized. For instance melamine forms an adduct with both H2SO4 and HNO3. They are relatively safe and very stabile solid reagents with can be used in reactions without solvent using mechanical and pneumatic low pressure mixing or ultrasonic mixing. Melamine can be used in the latter half of CL-20 synthesis. Melamine forms adducts very easily with hydrogen bonding with acids cyanuric and complexes with boric acid. Melamines conversion to carbon nitride can be used in photocatalytic production of hydrogen or hydrogen peroxide using sun light as the only energy source. Melaminium sourced CN can be used as catalysts and early forms (prior to 1800c heating) of melaminium derived BN can act as modifiers in the energetic profiles of propellants and explosives, dramatically altering their behavior in decomposition. That's not even getting into the polymer and adhesive applications. Melamine can be used in desensitization of explosives as well. They make LEDs in the blue light spectrum from melem directly and a salad bar of other supramolecular creations and complexes. And that's only a slice of its pie. Guanidium branches from urea are even more dizzying. It is absolutely incredible and is in tremendous critical usage and production world wide. To read someone suggest it's uses are limited is baffling. I must disagree, it is useful.

The other aspects of urea which make it interesting are its high volume consumption globally, which makes it absolutely critical. It is not like ammonium nitrate which can be supplemented, urea cannot be supplemented. But even if it were to be regulated out of circulation, which is not possible, it can be easily produced. The urea production patents should be reproducible using a couple of exhaust manifolds and exhaust pipes from a junk yard and a welder. But that's only necessary if it's of novel interest because the guy down the road sells urea @$300/ton. I asked him. He said he will dump directly into any container, and can even fill truck beds as long as it's below a certain height from the top of the bed and reduced speeds are used to prevent urea contamination during transport.

[Edited on 7-3-2021 by Hey Buddy]
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