Highly stable NaFeO2-Fe3O4 composite catalyst from blast furnace dust for efficient production of biodiesel at low temperature

Abstract

Highly stable catalysts were prepared by wet impregnation of blast furnace dust (BFD) in Na2CO3·H2O, Na2CO3·10H2O, NaHCO3 and Na2CrO4 solution and subsequent calcination at 300–600 °C. At low temperature of 65 °C for 2 h with methanol/oil molar ratio of 15/1, high biodiesel yield of 100 wt% was obtained with for both Na2CO3·H2O@BFD300 and Na2CO3·H2O@BFD400 catalyst (impregnating with Na2CO3·H2O solution and calcining at 300 and 400 °C) at 7 wt% for the first use. Na2CO3·H2O@BFD300 catalyst exhibited outstanding stability and recyclability with biodiesel yield of 100 wt% at the fifth use (93 wt% at the twelfth use) owing to the formation of stable and active nanocomponents of NaFeO2 (32.42 nm) and magnetic nanocomponent of Fe3O4 (size of 3.14 nm and magnetization of 6.16 Am2/kg). This study finds a solution to use solid waste for the green production of biodiesel.