Safe operating conditions of isoperibolic homogeneous semibatch reactions: Effect of mixing heat

The mixing heat in a semibatch reactor may lead to an increase or decrease of the reaction initial temperature, which has an impact on the safety of the reaction. In this paper, the effect of mixing heat on the safe operating conditions of isoperibolic homogeneous semibatch reactions was studied. Mass and energy balance models considering mixing heat were constructed. Based on the balance models, boundary diagrams and adiabatic temperature diagrams were compared under different mixing heat levels. The mixing heat and reaction heat of esterification reaction between propionic anhydride and sec-butanol were measured by EasyMax. According to the experimental results, the effect of mixing heat on the thermal runaway critical cooling temperature was investigated. The results indicated that the mixing heat had a significant effect on the thermal behavior state of the reaction. The critical criterion considering the mixing heat can more accurately predict the safe reaction operating conditions for the isoperibolic homogeneous semibatch reactions. This work provided helpful suggestions for predicting safe operating conditions of reactions at different mixing heat effect levels.