Hydroxyurea Reaction With HNO_2 and Pu(Ⅲ) Stabilization

Reaction kinetics of hydroxyurea(HU) with HNO_2 in nitric acid solution is studied.The results show that the reaction rate follows the equation as:-d c (HNO_2)/d t = k_0c (HNO_2) c ~(1.1)(HNO_3)( c ~0(HU)),where k_0 =(0.18±0.01) L~(1.1)·mol~(-1.1)·s~(-1) at 10 ℃ and c (HNO_2)=5 mmol/L;the activation (energy) is deduced to be about 63 kJ/mol.The reaction appears zero order relative to HU.Kinetic study performed at various NaNO_3 solutions shows that salt ions have little effect on the reaction rate.Excess HU can stabilize Pu(Ⅲ) well in nitric solutions.