Green and effective catalytic hydroconversion of an extractable portion from an oil sludge to clean jet and diesel fuels over a mesoporous Y zeolite-supported nickel catalyst

Abstract

A mesoporous Y zeolite (MPYZ)-supported nickel catalyst (Ni/MPYZ with 10% of Ni loading) was prepared by modifying deposition-precipitation (MDP) to uniformly disperse Ni nanoparticles (NNPs) onto MPYZ. An oil sludge (OS) was exhaustively extracted with isometric carbon disulfide and acetone mixed solvent to obtained the extractable portion (EPOS) in the yield of 90.6%. EPOS was subjected to the catalytic hydroconversion (CHC) over Ni10%/MPYZ at 160 °C under 5 MPa of initial hydrogen pressure (IHP) for 18 h in n-hexane to afford catalytically hydroconverted EP (EPCHC). The results show that alkenes, aromatics, and heteroatom-containing compounds (HACCs, some of which are also aromatics) in EPOS were completely converted to chain alkanes and cyclanes. Ni/MPYZ can effectively activate H2 to biatomic active hydrogen (H⋯H) and heterogeneously split H2 to relatively mobile H+ and immobile H− attached on the surface of Ni/MPYZ. The transfer of H⋯H and H+ to EPOS plays crucial roles in the CHC of EPOS. Such mechanisms are evidenced by the CHC of benzyloxybenzene over Ni/MPYZ. Ni10%/MPYZ maintained high activity for the CHC after 5 repeated cycles.