Abstract
The reaction between nitric acid and thiocyanate has been studied both in batch and flow configurations. The batch reaction is autocatalytic with an induction period which is decreased by the addition of HNO2. At the nitric acid concentrations employed (1–10 M), a red NOSCNH+ intermediate is formed. The reaction in a flow reactor exhibits bistability. A model involving competitive reactions of SCN− and NOSCNH+ with NO2 is suggested, and computer simulations with this model give good agreement with both the batch and flow experiments.