SCWR Chemistry Issues: Hydrothermal Stability of Hydrazine

Abstract

Hydrazine is one of the potential candidates for chemistry control for both in-core and out-of-core components of a SCWR. At present, systematic experimental data on hydrazine chemistry is mainly limited to sub-critical water conditions. Supercritical water flow-through test facility for the study of hydrothermal processes is described. The decomposition of hydrazine in aqueous solution is examined along the 25 MPa isobar. The obtained first-order rate constant for the thermal decomposition of hydrazine increases from 3.73 × 10^-4 s^-1 at 473 K to about 0.31 s^-1 at 725 K.