A method for increasing the concentration of olefins cracking additives

A method for increasing the concentration of olefins cracking additive comprising the modified MFI zeolite, aluminum phosphorous containing first inorganic clay binder, an inorganic binder, and other additives, a Group VIII metal, with or without a second clay; the aluminum phosphate inorganic binder containing a first clay-mentioned components include aluminum, phosphorus and a first component of clay, said modified MFI molecular sieve containing phosphorus and is selected from Fe, Co, Ni, Cu, Mn, Zn , Sn, Bi of one or more transition metals, and its use as a probe molecule trimethylpyridine obtained at 1633cm-1 IR spectrum no absorption peak be in a position of which is phosphorus distribution D 0 ~ 0.8, D a molecular sieve grains were characterized by TEM-EDX phosphorus content and phosphorus content ratio of zeolite crystal at the center from the edge to the center of one-fifth of. The additive is used in catalytic cracking, catalytic cracking LPG can increase the yield and improve the ethylene, propylene and isobutylene and other olefins yield fluid catalytic cracking LPG increase in the concentration of light olefins, to improve the heavy oil conversion capacity of the catalyst composition improve dry gas, coke selectivity.