Detailed Chemical Kinetics for Thermal Decomposition of Low Molecular Weight-Methyl Esters Generated by Using Biodiesel Fuel

摘要

Low molecular weight-methyl ester (LMW-ME), which was reported in our previous study, was generated by the use of biodiesel fuel (BDF) with a diesel power generator. In this article, the detailed chemical kinetics for the thermal decomposition of LMW-MEs was investigated at atmospheric pressure and a temperature range of 773 to 973 K. Six standards of LMW-MEs were used for thermal decomposition in a continuous flow reactor. The kinetic data, such as reaction orders, activation energies, and rate constants, were then calculated. The reaction orders and activation energies of the thermal decomposition reactions of C_4, C_5, C_6, C_7, C_8, and C_9 were 1.13, 0.96, 1.17, 0.80, 0.99, 0.84, and 312.04, 117.37, 87.29, 62.94, 74.80, 75.79 kJ mol_(-1), respectively. The decomposition of LMW-MEs with higher carbon numbers was faster than those with smaller carbon numbers, except for C_8. The C_4 methyl ester was stable and abundant in the product of the decomposition as well as in the exhausted gas from the engine combustion using BDF. This kinetic data will be applied to modeling study on BDF decomposition and engine technologies to mitigate toxic emissions from BDF combustion.