Sciencemadness Discussion Board

getting rid of urea

Random - 19-7-2013 at 00:20

I have npk fertilizer and i need to hydrllize urea so i can recrystalize kno3 from it. I tried to add ca(oh)2 solution to see if it works and almost none at all caco3 precipitate was seen. It would. Be. Indicator that co2 escaped from urea and that it was hydrolized. Why. Doesnt it work? Or is it just slow rеaction?

Sorry for. Grammar mistakes im on a mobile and its hard to type

woelen - 19-7-2013 at 00:30

If urea is not hydrolyzed, then it also does not give a precipitate with calcium ions. The hydrolysis reaction of urea to ammonium carbonate is very slow in plain water. Maybe if you allow it to stand for days or weeks, then you'll see the effect. Urea as fertilizer hence works for weeks, over the weeks it slowly hydrolyses and slowly gives off nitrogen in a form, suitable for plants to take up.

testimento - 19-7-2013 at 01:40

Well well, I have some fertilizer with AN and urea mixed and I'd be interested too how to get the urea off. Primary method would be to separate the urea as it is, because I need urea, but if its not possible, I want to recover the ammonia gas.