Metal-substituted layered Fe-based oxides as a solid base catalyst

Metal-substituted KFe11O17 with a β-ferrite structure was synthesized as a solid base catalyst for biodiesel fuel production. Among the metal-substituted samples, Mn-substituted KFe11O17, KFe10MnO17, showed the highest catalytic activity for the transesterification of triacetin with methanol and a higher catalytic activity than that of CaO, MgO, and KF/Al2O3 as typical solid bases. CO2-TPD analysis showed that a weak base site was formed mainly on KFe10MnO17. Since a high concentration of methoxy species as an active site in this reaction could be formed during reaction over the weak basic site, KFe10MnO17 can be considered an effective catalyst.