engleski

The influence of the reaction parameters and the feedstock type on the synthesis of fatty acid propyl, butyl, isobutyl, pentyl, and isopentyl esters

Fatty acid alkyl esters (biodiesels) can be synthesized via transesterification reaction from a variety of feedstocks and alcohol isomers, in a presence of a catalyst, influencing the end biodiesel conversion. The use of higher and branched alcohol isomers in biodiesel synthesis is justified through the potential improvement in biodiesel’s application properties, e.g. lowtemperature properties or cetane number, [1] whereas the implementation of waste feedstock further contributes to the sustainability of the entire process. [2] The presence of the structural branching, as well as the molecular weight of the reactants used dictates the rate and the efficiency of transesterification reactions. In general, the increase in the alcohol chain length and the presence of structural branching in reactants leads to a decrease in the reaction conversion, due to higher steric hindrances. [3] Here, fatty acid propyl, butyl, isobutyl, pentyl, and isopentyl esters were synthesized from corresponding alcohols and a selected feedstock type (sunflower oil, rapeseed oil, coconut oil, animal fat or waste cooking oil), in a presence of potassium hydroxide as a catalyst, at a constant temperature of 60 °C. The influence of the reaction time (up to 120 min), the molar ratio of the reactants (5:1-12:1), and the mass fraction of the catalyst (1-3 wt%) on the reaction conversion was studied. The results showed that the molar ratio of alcohol to oil/fat, and the mass fraction of the catalysts are the most significant reaction parameters, whose increase generally leads to an increase in the reaction conversion.

biodiesel ; transesterification ; propanol ; butanol ; isobutanol ; pentanol ; isopentanol

nije evidentirano