Abstract: The performance of phosphorus containing magnesia-alumina spinel for vanadium trapping in FCC process was investigated. The results of FFB tests demonstrate that the phosphorus containing magnesia-alumina spinel can be used to match FCC catalysts with different rare earth content and to improve the product distribution of heavy metal contaminated catalysts. When the composite catalyst consisting of the FCC catalyst containing 4.5% rare earth oxides and the phosphorus containing magnesia-alumina spinel, the total liquid yield is increased by 0.6%, the coke selectivity is improved. However, the dry gas selectivity is similar to FCC catalyst only. Compared with the FCC catalyst, the phosphorus containing magnesium aluminate spinel can preferentially capture the porphyrin vanadium and form a stable compound, thus attenuates the detrimental effect of vanadium on FCC catalysts in steaming aging process.

Key words: FCC, Mg-Al spinel, vanadium, trapping