(218e) Breakdown Mechanisms for Methyl-Esters

Biofuels are liquid, solid, or gaseous fuels derived from renewable biological sources. Biomass can be burned directly for thermal energy or converted to other high-value energy sources including ethanol, biodiesel, methanol, hydrogen, or methane. Biodiesel is a biologically derived diesel fuel substitute created by chemically reacting vegetable oils or animal fats with an alcohol (methanol is the usual choice) to produce fatty acid methyl esters of the R-(C=O)-O-R' form (where R and R' are carbon chains of alkyl and alkenyl) with as many as 16-18 carbon atoms. Biodiesel is the name given to these esters when they're intended for use as fuel. Blends of up to 20% biodiesel (mixed with petroleum diesel fuels) can be used in nearly all diesel equipment and are compatible with most storage and distribution equipment. In this work we report a detailed analysis of the breakdown kinetic mechanisms for methyl-esters using theoretical approaches. Electronic structures and structure-related molecular properties of reactants, intermediates, products and transition states were explored at the BH&HLYP/cc-pVTZ level of theory. Rate constants for the main reaction pathways are computed for the temperature range of 300-2500 K.