Abstract: In order to enhance the utilization of olefins and to produce more propene, FCC dry gas was introduced as partial feed in the process of preparing propene from mixed C4. A series of ZSM-5 zeolite catalysts loaded with various MoO3 contents were prepared by incipient wetness procedure to realize the coupling of cracking reactions and metathesis reactions. The MoO3/ZSM-5/Al2O3 catalysts were characterized by XRD，Py-FT-IR and BET method to study the effect of MoO3 content on the catalyst performance．Test results showed that the acidity, surface property and pore structure of the catalyst were affected by the loading of MoO3．Based on correlating the evaluation results of fixed bed micro-reactor and the MoO3 contents，it was found that under the conditions of a reaction temperature of 450 oC, a dry gas/mixed C4 volume ratio of 4 and a GHSV of 120 min-1, MoO3/ZSM-5/Al2O3 catalyst with suitable MoO3 content was in favor of promoting metathesis reactions between ethene and 2-butene, and thus the propene yield was increased．A maximum propene yield of 27.85% was obtained over a catalyst with a MoO3 content of 4%．

Key words: dry gas, mixed C4, propene, molybdenum