Ethanolysis of Soybean Oil Using Mesoporous Molecular Sieves

Abstract

This study evaluates the use of nanostructured materials as catalyst in biodiesel production from soybean oil using ethanol as transesterificant agent. Ethanol can be environmentally advantageous over methanol (more frequently used as reagent in biodiesel production) because it can be obtained from renewable sources whilst methanol is usually derived from mineral sources. The catalyst (La50SBA-15) has lanthanum oxide as active phase which was inserted by isomorphous substitution into the SBA-15 network. The LaSBA-15 mesoporous molecular sieves were synthesized using pluronic (P123) dissolved in aqueous HCl solution with tetraethyl orthosilicate and a given amount of hydrated lanthanum chloride (Si:La = 50) at 333K. The reaction was performed using the molar ratio soybean oil:ethanol of 1:20 at inert atmosphere (N2) at 343K with 1wt% of catalyst mass relative to total oil mass added to the reaction mixture. The reaction was evaluated for ethyl ester conversion after 3h and 6h. The ethyl esters content was measured using low frequency HNMR spectroscopy (200MHz). A conversion of soybean oil in ethyl esters (biodiesel) of 80% after reaction time of 6h was obtained. The La50SBA-15 heterogeneous catalyst showed good performance in the ethanolysis of soybean oil, comparing well with previous reports for methanolysis of soybean oil.