Industrial Development Of FCC Catalyst For Increasing Diesel Yield And Reducing Olefins In Gasoline

In order to satisfy the requirements of the new national gasoline formula standard(GB17930-1999) and optimize the economic effect of oil refineries, a new FCC catalys(tID-RO FCC catalyst)for reducing the olefins in gasoline and increasing the yield of diesel has been developed by the Lanzhou Petrochemical Company of PetroChina and produced on a large scale successfully in the catalyst plant of Lanzhou Petrochemical Company. The catalyst which is composed of a new type of USY zeolite with effective activity for hydrogen transfer and high selectivity for diesel as the main active component, the optimized macro-pore support and shape selective molecular sieve ZSM-5 can increase the conversion of heavy oil, as well as inhibit effectively the excessive cracking of middle distillate. The results of medium-sized experiment show that this catalyst can increase the yield of diesel by 2% and reduce the olefins in gasoline by 8%-12% when compared with other olefins reducing catalysts. The initial industrial application in Dalian Petrochemical Company has shown that a 10% reduction of olefins in gasoline can be achieved when the yield of diesel kept in a high level. The RON of gasoline was kept stable or decreased slightly with an ideal product distribution. The comprehensive reaction performances of the olefins reducing catalyst are improved; good social and economic effects are obtained.Based on the good industrial application results, the catalytic reaction mechanism of reducing olefins in gasoline and increasing the yield of diesel, the relationship between hydrogen transfer index, olefins contents and products distribution and the basic factors that influence the yield of diesel were studied by using the techniques of XRD, IR spectra, DTA, MA etc. Moreover, the influence of the support type, zeolites contents and shape selective performance of ZSM-5, the function of phosphorus on zeolite modification and the modification conditions of active alumina on catalytic reaction performance was discussed and investigates deeply in this dissertation. Theevaluation of this catalyst in fix-bed reactor and minor scale riser together with industrial application results were also summarized in details, which can provide the theoretical and experimental basis for modifying and optimizing the preparation process of this catalyst.