False isokinetic relationships found in the nonisothermal decomposition of solids Original Research Article

Three types of false isokinetic relationships (IKR) arising due to variation of (i) reaction model, (ii) conversion, (iii) heating rate are discussed. Both the origin of IKRs and the meaning of the isokinetic temperature (Tiso) is elucidated. It is shown that IKRs (ii) and (iii) in nonisothermal reactions are inherent only to multi-step processes. Tiso evaluated from an IKR (i) is a temperature related to a specific conversion. Tiso evaluated from IKRs (ii) and (iii) is an arbitrary temperature within the temperature region of the process provided that a valid reaction model is used to describe the kinetics of the process.