Bifunctional Effects of MoO3/S-ZrO2 and Mo2C/S-ZrO2 Catalysts in Transesterification of Groundnut Oil

Abstract

Successful doping via impregnation and carburization under CH₄/H₂ atmosphere were respectively employed to achieve the formation of MoO₃/S-ZrO₂ and Mo₂C/S-ZrO₂ catalysts. The synthesis of both materials was confirmed as illustrated by the binding energies associated with XPS spectra of C1s, Mo 3p and Mo 3d states. In addition to compatible BET surface areas of 120 and 97m²g^-1, both catalysts were found to exhibit appreciable densities of surface Mo species as revealed by the N₂-adsorption data. These species enhanced catalytic activity and prompted the catalyst to exhibit bifunctional properties during transesterification of groundnut oil. When compared with the support system (i.e. S-ZrO₂), the overall catalytic performance at 60^oC, 0.5g of catalyst and 1:6 (oil: methanol) followed the trend S-ZrO₂ < MoO₃/S-ZrO₂ < Mo₂C/S-ZrO_2. Another appreciable result is the conformity of the derived biodiesel with international specifications approved by ASTM for B100 and other fuel grades of methyl esters.