Isomorphous replacement of Si by Ti in the low aluminum-containing zeolite Beta framework has been achieved by direct synthesis. The crystallization must be carried out in the absence of alkali cations, as they promote the precipitation of amorphous titanosilicate. The incorporation of Ti to the framework has been characterized by XRD, i.r., and thermal analysis. Ti is believed to perform a stabilizing role of the Beta framework similar to that of Al. The large pores of [Al, Ti]-Beta compared to TS-1 allow the use of this material as a catalyst in the selective oxidation of cyclododecane with hydrogen peroxide.
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