Study On Preparation And Structure Of Pillared Rectorite Composites

Rectorite is a clay mineral with expandable layer structure.Rectorite, as an unique structural features material,has high cationic exchange capacity and better thermal stability.Pillared rectorite have many excellent characteristics, such as large specific surface area, exchangeable cations and good thermal stability. Pillared rectorite can be studied as SCR catalytic materials.This thesis describes the preparation, the structure and application of rectorite.The TiO2pillared rectorie and Al2O3pillared rectorie are prepared with the method of ion-exchange.Pillared rectorite composites are obtained by loading the traditional SCR catalyst active component V and W.The pillared rectorite are characterized by XRD, SEM, TEM and N2absorption-desorption.Small angle XRD tests indicate that the ordered structure of titanium pillared rectorite composites are destroyed. It is due to the different particle sizes of polyhydroxy-Ti cations as pillaring agent. The aluminum pillared rectorite composites have stable layer spacing. Compared with the original rectorie, the layer spacing of aluminum pillared rectorite are increased about0.25nm.The pillaring agent of polyhydroxy-Al cations have the same particle sizes. The layered structure is more obvious and the specific surface area has a substantial increase. The specific surface area of the titanium pillared rectorite is42.9853m2/g and the specific surface area of the aluminum pillared rectorite is156.5273m2/g. Rectorite composites have a layered porous structure and the metal oxides are dispersed symmetrically on them. The HRTEM show the metal oxide uniformly load on the composite surface.