Investigation into Maximum Temperature of Synthesis Reaction and Accumulation in Isothermal Semibatch Processes

Abstract

Maximum temperature of synthesis reaction (MTSR), which is a function of the process temperature (<i>T</i>_p) and the maximum accumulation (<i>X</i>_ac,max), is an important criterion for process hazard assessment and reactor design. For isothermal reactions, <i>X</i>_ac,max is influenced by kinetics, thermodynamics and operating conditions. To analyze the behaviors of MTSR and <i>X</i>_ac,max, a mathematical model for isothermal homogeneous semibatch reactors is proposed. The influence of several dimensionless parameters (ν_ADa<i>R</i>_E, γ, Δτ) and reaction orders on MTSR and <i>X</i>_ac,max are also studied. It is found that the MTSR curves for slow and highly exothermic reactions tend to present a “S” shape. On the basis of the above analysis, a semiempirical criterion is suggested to quantificationally decide whether the MTSR curves are monotonously increasing or not. A typical esterification reaction is conducted to validate the proposed model and the semiempirical criterion. Applications using the mathematical model and the criterion in hazard assessment and process optimization are also discussed