Efficient biodiesel production from oleic acid using metal–organic framework encapsulated Zr-doped polyoxometalate nano-hybrids

-TPD) analysis. The as-prepared ZrSiW/UiO-66 had excellent catalytic activity in the esterification of oleic acid with methanol, higher than that of ZrSiW/Fe-BTC catalyst, owing to the fact that ZrSiW/UiO-66 nano-hybrids have high acidity, large specific surface area and pore volumes, and relatively large average pore sizes. Furthermore, the reusability and stability of nano-hybrids were also evaluated, and it was found that the stability of ZrSiW/UiO-66 catalyst was better.