Kinetics of the combustion of olive oil. A semi-global model

• A kinetic model, including vaporization and reaction, is proposed.
• Two TG apparatus have been used, so the results can be compared.
• The kinetic model is supported by TG-MS and TG-IR runs.

A kinetic study of the combustion of olive oil has been carried out under different conditions by thermogravimetry using two different TG apparatus. Several TG runs were performed at air, N2:O2 = 4:1 and N2:O2 = 9:1 under dynamic conditions and a dynamic + isothermal regime (constant heating rate until the set temperature was reached with the set temperature maintained constant thereafter). On the other hand, a number of dynamic runs were carried out on waste olive oil and waste mixed oil. Based on an overall analysis of the data, a scheme of four decomposition steps was proposed and kinetic parameter values were calculated by integration of the differential equations and by minimizing the squared differences between the experimental and calculated values. An examination of the influence of the initial mass on TG runs was performed on the assumption of vaporization + chemical oxidation processes. The thermal decomposition was also carried out in dynamic runs at air atmosphere using TG-MS and TG-IR in order to validate the scheme of proposed reactions, the hypothesis of the formation of a carbonaceous residue and to study the evolution of several compounds.