Investigation To Typical Thermal Runaway Parameters For Liquid-liquid Semibatch Reactions Under Kenetically Controlled Condition

Maximum temperature of synthesis reaction?MTSR?and maximum accumulation(X_ac,max)are the important parameters of risk assessmen of runaway reactions.However,the existing researches on MTSR and X_ac,max mainly take second order homogeneous reactions as objects.Therefore,systematically investigation to MTSR and X_ac,max for liquid-liquid semibatch heterogeneous reactions which was keneticlly controlled is necessary and has an extremely important significance.Fistly,based on dimensionless mathematic model of isothermal heterogeneous semibatch reactors,MATLAB numerical calculations reveal that X_ac,max is in inverse proportion to temperature and MTSR trends to be“S”shape,when reaction has high adiabatic temperature rise and high activation energy.This paper theoretically derivates a mathematical expression for X_ac,max and a theoretical criterion to judge whether MTSR increases with T increasing have been developed.Next,to validate the MTSR increasing criterion,the nitration of 4-chloro benzotrifluorid by mixed acid wac chosen as typical reaction,and conducted isothermal experimets at 37??47?and 52?.The experiments results show that the behavior of MTSR is satisfied with the prediction of criterion,which verifies the correctness of MTSR increasing criterion.Finally,take consideration of the heat effect of dilution,this paper make correction of target temperature formula,then conduct isoperibolic experiment to validate applicability of the MTSR increasing criterion.This criterion could judge whether isoperibolic semibatch reaction process is correspond to QFS?Quick Onset,Fair Conversion,Smooth Temperature?area.This paper conduct systematically investigation to MTSR and X_ac,max,and MTSR increasing criterion applied for kinetically controlled semibatch reaction with arbitrary reaction order is proposed.This criterion criterion could not predict the variation of MTSR under isothermal mode,but also help judge whether the reaction process is correspond to QFS for isoperibolic mode,which helps make contributions to safer industrial operation.