Modification of a ZSM-5 catalyst by La for use in fluid catalytic cracking

The influences of La addition on the properties and the performance of xLa/ZSM-5 additives with various La loading (x is molar ratio of La/Al, x=0.25-1) for vacuum gasoil (VGO) cracking reactions were studied. Samples were deactivated via steaming treatment with 100% steam, 20hours, 816 degrees C. The highest promoting effect was obtained with 0.25La sample. The higher La loadings decrease the enhancement effect of La. XRD, BET and NH3-TPD results demonstrated that the use of low La3+ concentration solution during La addition step could lead to a better interaction of La3+ with ZSM-5 framework and increase the promoting effect.