A novel organic–inorganic hybrid membrane as heterogeneous acid catalyst for biodiesel production was prepared from zirconium sulfate (Zr(SO4)2) and sulfonated poly(vinyl alcohol) (SPVA). The structure and properties of the hybrid catalytic membrane were investigated by means of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), thermogravimetry (TG), transmission elec-
tron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The catalytic performance of the hybrid membranes was tested by the esteri?cation of the acidi?ed oil with methanol. It was found that
the Zr(SO4)2 particles were better dispersed in SPVAmatrix as a result of the stronger interaction between Zr(SO4)2 and SPVA compared with Zr(SO4)2/poly(vinyl alcohol) (PVA) hybrid membrane. Esteri?cation results showed that the conversions of free fatty acid (FFA) in acidi?ed oil were 94.5% and 81.2% for Zr(SO4)2/SPVA and Zr(SO4)2/PVA catalytic membranes, respectively. The stability of Zr(SO4)2/SPVA cata-lytic membrane is superior to Zr(SO4)2/PVA catalytic membrane.
