催化裂化反应类型及其相互作用对产物分布和产品组成的影响

以大庆蜡油掺30％减压渣油为原料油分别用催化剂A（只含有Y型分子筛）和催化剂B（含有较多的ZSM-5分子筛）在新结构提升管装置上进行裂化反应试验；并采用烯烃模型化合物1-庚烯用催化剂A在固定流化床反应器上进行了裂化反应试验。试验结果表明，双分子裂化反应历程在催化剂A上发生机率较大，表现为较低的干气产率，较低的汽油烯烃含量；单分子裂化反应在催化剂B上发生机率较大，表现为较高的液化气和丙烯产率，产品含有较高的烯烃。1-庚烯在催化剂A上反应，具有较高的丙烯选择性，同时干气产率较低，烯烃下降幅度较大。烯烃是单分子裂化反应和双分子裂化反应理想的连结物，将单分子和双分子裂化反应特点充分发挥，从而得到较高的丙烯产率、较佳的产物分布和较低的汽油烯烃含量，为开发生产清洁汽油组分并增产丙烯的催化裂化工艺提供试验和理论依据。

STUDY ON EFFECT OF CATALYTIC CRACKING REACTION PATTERNS AND THEIR INTERACTION ON PRODUCT SLATE AND PRODUCT COMPOSITION

Experiments on cracking of Daqing VGO blended with 30% VR over catalyst A having Y zeolite and catalyst B having mostly ZSM-5 zeolite were conducted in a pilot plant with a new structure riser reactor. Using heptene as model compound over catalyst A was conducted in a fixedfluidized bed reactor. The experimental results showed that bimolecular reaction pattern was dominant over catalyst A, which resulted in lower dry gas yield and lower olefin content in cracked naphtha. Differently, monomolecular reaction was dominant over catalyst B, having higher LPG yield with higher propylene content. The cracking results of heptene as model compound showed higher propylene selectivity, lower dry gas yield and higher olefin conversion. Olefins were the ideal mediator between monomolecular reaction pattern and bimolecular reaction pattern. With the aid of olefins, both reaction patterns can bring fully into effect to obtain higher propylene yield, better product slate and lower olefin content in cracked naphtha, which provides experimental and theoretical basis for developing a novel FCC technology for clean gasoline component and propylene production.