Urea Nitrate Synthesis

Urea nitrate is a relatively cheap and easy explosive to produce. The easiest method of production involves direct treatment of urea with nitric acid. The method outlined here requires only a slight bit more work, and uses ammonium nitrate and HCl in place of nitric acid. I prefer to use nitric acid for other things, and so this is my method of choice for urea nitrate production.

All that's needed here is urea, ammonium nitrate, and some HCl. Two solutions are made - 39.5g of ammonium nitrate in 25 ml water, and 27g urea in 35 ml water (scale up as needed). These two solutions are then mixed, leaving a clear solution of the two. This solution is then heated to 80 degrees C in a water bath. Once the temperature is reached, the beaker is removed from the water bath. Then, 50 ml of 31.45% HCl is added to the solution with rapid stirring and left to steam. This is then allowed to cool with further stirring. Crystals of urea nitrate will become visible in the solution after some cooling has occurred, and stirring is continued.



The solution is allowed to cool with further stirring, breaking up the clump of crystals every once in a while. The solution is then placed in the freezer for a few hours, or overnight, and the clump of crystals once again broken up. The crystals are then filtered and left to dry. The urea nitrate is then ready to be used. Some of the urea nitrate seen here will be used for conversion to nitrourea.

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