A METHOD FOR THE PREPARATION OF SILICA SUPPORTED Mg-AI LAYERED DOUBLE HYDROXIDE (LDH) NAN0 SHEET BASED COMPOSITE CATALYST FOR DECOMPOSITION OF N2O IN SYNTHETIC AUTOMOBILE EXHAUST CONDITION

摘要

In the present invention, there is provided a process for the preparation of sol-gel derived silica based powdered nano-oxide catalysts useful for the treatment of toxic gases by using composite materials containing Layered Double Hydroxides (LDH) over silica as the carrier. The process combines reacting alkoxides in a well designed manner so as to prepare silica supported LDH gels of Mg-A1 type possessing positive layer charge, in different si1ica:LDH ratio in a non-aqueous medium. The gel thus obtained after drying and calcinations at ambient temperature result in the formation of active mixed metal nano oxide catalysts at nanometer dimension for carrying out decomposition of N2O gas in a He flow in various flow rates at 400 to 550°C temperature in a tubular stainless steel reactor tube.