Ammonium nitrate

Ammonium nitrate is an interesting compound used in the explosives industry and as a fertilizer. It's a major component of the industrial explosive ANFO. Ammonium nitrate is also used in some coldpacks. I plan to use ammonium nitrate to make nitroguanidine, and eventually aminotetrazole. The cheapest way to obtain ammonium nitrate is to extract it from fertilizers or coldpacks, however, I didn't do this.

I tried making some ammonium nitrate from potassium nitrate.

To a 1000ml beaker I added a solution of 46g of sodium bisulphate in water. Then I added 34g of potassium nitrate in solution. I stirred the mixture well. The pH of the mixture was acidic and I added ammonia solution untill the pH became neutral. I transferred the mixture to a hotplate and boiled it down until I could see crystals forming. This was potassium sulphate. The mixture was chilled down in the freezer and more potassium sulphate crystals precipitated. I filtered all the precipitate off and collected the clear filtrate.

The filtrate was allowed to evaporate, yielding 65g of slightly wet ammonium nitrate.

NaHSO4 + KNO3 ==> HNO3 + KNaSO4   //   HNO3 + NH3 ==> NH4NO3