Spontaneous reductive decomposition behavior of hydrogen permanganate in water for chemical decontamination of nuclear power plants.

The spontaneous reductive decomposition behavior of HMnO4 in water as a function of the initial HMnO4 concentration and reaction temperature was investigated. The decomposition of HMnO4 was fast in the early stage of the reaction and thereafter slowed down significantly, regardless of the initial HMnO4 concentration. The loss of HMnO4 by spontaneous reductive decomposition increased with increasing reaction temperature. Based on the experimental results and the classical nucleation theory, a mathematical model was developed using a combination of two first-order reactions representing the nucleation and crystal growth of MnO2 to predict the spontaneous reductive decomposition behavior of HMnO4. [ABSTRACT FROM AUTHOR]