XPS STUDY OF INTERACTION OF TITANIUM SPECIES WITH DIFFERENT INTERNAL ELECTRON DONORS ON Z–N CATALYSTS

TiCl4/MgCl2, TiCl4/MgCl2/donor catalysts and TiCl4/donor complexes were prepared in this experiment; the donors are EB, DNBP, DBPG, DBW, PPDE, and BMMF respectively. Chemical states of Ti on the surface of MgCl2-supported Z–N catalysts were analyzed with X-ray photoelectron spectroscopy (XPS). The interaction among components of a catalyst is characterized, and the function of internal donor in the catalyst was demonstrated according to the change of binding energy of Ti2p3/2. We may conclude from the experiment that the kind of internal donors influence the electron density around titanium, and further the electron density around active titanium species effect catalyst activity to some extent. It was also noted that the interaction between internal donors and titanium is weakened remarkably by moisture and oxygen in ambient.