Abstract :
This paper deals with an experimental batch mode study of a chemical homogeneous reaction: the dichromate-catalysed hydrogen peroxide decomposition. The thermodynamic properties and the kinetic parameters of the reaction are simultaneously determined using a calorimetric approach. Various batch-operating modes (adiabatic, isoperibolic, or differential thermal analysis) are compared and it is shown that the determined parameters do not depend on the operating mode. A complete kinetic law is proposed. The reaction rate constant is assumed to follow the Arrhenius rate law. The Arrhenius parameters are determined as frequency factor k0 = 1.39 × 109 s−1 and activation energy E = 54.9 kJ mol−1. The measured enthalpy of reaction is ΔrH = −94 kJ mol−1. The reaction order is between 0 and 2 in hydrogen peroxide according to operating conditions and depends linearly on the initial dichromate concentration. The reaction can be managed by two parameters: on one hand the released reaction heat directly depends on the hydrogen peroxide concentration, and on the other hand, the kinetic rate can be increased in increasing the dichromate concentration.
