The Effect of Al~(3 ), Na~ , NH_4~ on Ti Content in the Preparation of Ti-ZSM-5

The effect of Al3 , NH, Na on the Ti content in the preparation of Ti-ZSM-5 by the isomorphous substitution of ZSM-5 using gaseous TiCl4 as titanium resource has been investigated. It is surprisingly found that although the direct ratio exists between the Ti content and the content of the skeletal Al: y=0.08x2 0.57x 1.23(here y represents TiO2% and x represents Al2O3%). but the catalytic activities of Ti-ZSM-5 for the oxidation of styrene sharply rise with the decrease of TiO2%. The skeletal Al hinders the Ti incorporation into the framework of molecular sieves characterized by FT-IR technique. At the same . NH ion has no effect on the Ti incorporation. but Na ion does.