Partial oxidation of vacuum residue over Al and Zr-doped α-Fe2O3 catalysts

Partial oxidation presents a novel method to produce liquid fuels, such as gasoline, diesel and vacuum gas oil, from vacuum residue (VR). Al and Zr-doped alpha-Fe2O3 catalysts were prepared for partial oxidation of VR. The catalysts were characterized by N-2 adsorption/desorption, X-ray diffraction, H-2 temperature programmed reduction, Raman, and X-ray photoelectron spectroscopy. The results showed that the specific surface area and pore volume of doped alpha-Fe2O3 increase, and Al and Zr are incorporated into alpha-Fe2O3 structure. XPS analysis indicated that several oxygen species appear in alpha-Fe2O3 surface, in which lattice oxygen is the majority. The doped alpha-Fe2O3 catalysts show better catalytic performance than alpha-Fe2O3 alone in partial oxidation of VR at 550 degrees C. When an Al and Zr-doped alpha-Fe2O3 with Fe/Al/Zr atomic ratio being 16: 1: 1 (FeAlZr-1) was used as catalyst, the gasoline and diesel yields are 11.5 wt% and 43.8 wt%, respectively. Furthermore, FeAlZr-1 shows good regenerability in partial oxidation of VR.