there is a us patent from 1955 for production of hydrazine from urea and nickel or iron metal at 140c. supposedly these compounds react to form hydrazine and nickel or iron carbonyl. nickel is said to work best because at this temperature the nickel carbonyl decomposes to form nickel metal and carbon monoxide making the process truly catalytic
while 20% of the iron carbonyl does not decompose.
these metal carbonyls are volatile liquids five times more poisonous than hydrogen cyanide, so this is for reference only. but i would like to ask if the process works. could someone post the heats of formation for urea, hydrazine and nickel and iron carbonyl and/or explain why or why not the process would work.