摘要
The addition of distillation residues to the FCC feedstock leads to increased vanadiumloading on catalyst and the problems in catalyst deactivation.The deactivation process is related tothe destructive attack on the zeolite crystallite by V<sub>2</sub>O<sub>5</sub>.Formation of low melting pointV<sub>2</sub>O<sub>5</sub>-USY-Na<sub>2</sub>O phases accelerates the diffusion of vanadium through the catalyst.A proposedmechanism,based on accelerated dealumination,is shown in the paper.Comparative vanadiumtrapping performances have been tested for FCC catalysts and the crystalline ABO<sub>3</sub> as an effectivevanadium trap is demonstrated in laboratory tests.
The addition of distillation residues to the FCC feedstock leads to increased vanadium loading on catalyst and the problems in catalyst deactivation. The deactivation process is related to the destructive attack on the zeolite crystallite by V2O5. Formation of low melting point V2O5 -USY -Na2O phases accelerates the diffusion of vanadium through the catalyst. A proposed mechanism, based on accelerated dealumination, is shown in the paper. Comparative vanadium trapping performances have been tested for FCC catalysts and the crystalline ABO3 as an effective vanadium trap is demonstrated in laboratory tests.
