Thermal decomposition characteristics and kinetics of methyl linoleate under nitrogen and oxygen atmospheres

摘要

The thermal decomposition characteristics of methyl linoleate (ML) under nitrogen and oxygen atmospheres were investigated, using a thermogravimetric analyzer at a heating rate of 10?°C/min from room temperature to 600?°C. Furthermore, the pyrolytic and kinetic characteristics of ML at different heating rates were studied. The results showed that the thermal decomposition characteristics of ML under nitrogen and oxygen atmospheres were macroscopically similar, although ML exhibited relatively lower thermal stability under an oxygen atmosphere than under a nitrogen atmosphere. The initial decomposition temperature, the maximum weight loss temperature, the peak decomposition temperature, and the rate of maximum weight loss of ML under an oxygen atmosphere were much lower than those under a nitrogen atmosphere and increased with increasing heating rates under either oxygen or nitrogen atmosphere. In addition, the kinetic characteristics of thermal decomposition of ML were elucidated based on the experimental results and by the multiple linear regression method. The activation energy, pre-exponential factor, reaction order, and the kinetic equation for thermal decomposition of ML were obtained. The comparison of experimental and calculated data and the analysis of statistical errors of pyrolysis ratios demonstrated that the kinetic model was reliable for pyrolysis of ML with relative errors of about 1?%. Finally, the kinetic compensation effect between the pre-exponential factors and the activation energy in the pyrolysis of ML was also confirmed.