Preparation of copper-titanium silicalite-1

Abstract

The effects of incorporating Cu atom directly into the TS-1 framework during the formation of TS-1 crystalline for the gas phase selective oxidation of 2-propanol were investigated under inlets conditions of 8 vol% of O[subscript 2] and 5 vol% of 2-propanol in the reaction temperature range of 100-500 [degrees Celsius]. The research found that TS-1 can be successfully modified by copper incorporation. Three forms of copper (II) ions exist in three different environments in the catalysts. Isolated copper (II) ions incorporated into the titania network were detected by ESR spectroscopy, exists on CuO phase (from the ESR results) and surface complexes of Cu ions with titania (from the XPS results). Temperature programmed desorption of ammonia (NH[subscript 3]-TPD) are used to determine the amount and strength of acid site to find the relationship between catalytic behavior and catalyst properties. From the catalytic reaction, it can be indicated that thecatalyst oxidation over Cu-TS-1 catalyst yields acetone more than TS-1 catalyst. The addition of Cu to TS-1 catalyst slightly affects the over all conversion of 2-propanol, but significantly increases the selectivity toward CO[subscript 2]. Nevertheless, there is no direct relationship between the content of Cu and the selectivity of propylene. Similarities between structure, properties and catalytic activity of TS-1 and Cu-TS-1 catalysts exists. This research indicated that lower copper concentration, higher acid strength. In addition, an appropriate combination of acid sites should exist to improve the catalytic activity and selectivity.