Preparation Of A Novel Catalyst Carrier

Metallic carrier has been one of the most developing catalyst carriers because of its many merits, such as large specific surface area, high porosity, good shock-proof property and low heat capacity, etc. But it also has some disadvantages that prevent further development of metallic carrier: The heat expansion coefficient of ceramic wash coat and that of metal substrate are different, which make the ceramic coat easily to desquamate. Therefore it has been more and more urgent to develop a novel manufacture method to solve the matchless of heat expansion between ceramic coatings and metallic substrates.A novel catalyst carrier was developed referring to the manufacture technique of the shell in investment casting in this dissertation. Firstly, high temperature stable metallic wire was coated with a waxen film, and then submersed into water glass suspersion of y - Al2O3to get another layer. The wax was removed through a lower heat treatment. Thus there was a clearance between metallic substrates and / - A12O3 coatings. Finally, a layer with high temperature stability, certain specific surface area and porosity was made through higher heat treatment. The layer could be provided with a secondary alumina wash coat or an active exponent directly in a conventional way. The composition and quality of the products were studied using a series of instruments.Five chapters were included in this dissertation. Some other's recent research work about the catalyst carriers has been introduced in the first chapter. While in the second chapter, common catalyst carriers were introduced. The manufacture process of the shell in investment casting was included in the third chapter. All of our experimental work was introduced in the fourth chapter. And the last chapter is conclusionpart.