T HIS STUDY investigates the activity of copper-doped catalysts supported on sulfated zirconia (SZ) for the esterification of Free Fatty Acid (FFA).Three catalysts SZ, Cu/SZ (sol) and Cu/SZ (imp) were prepared.The latter two catalysts contain 10% Cu supported on sulfated zirconia (Cu/SZ) prepared by wet impregnation (Cu/SZ/ (imp)) and sol-gel method (Cu/SZ/ (sol)).The catalysts were characterized ...