CATALYST FOR PURIFYING EXHAUST GAS AND ITS PREPARATION

摘要

PURPOSE:To enhance the contact efficiency of a catalyst and carbonaceous fine particles, by supporting a mixture of a refractory inorg. powder and a refractory fibrous substance by the gas contact surface of a refractory three- dimensional structure in a protruded state and further supporting a platinum group element thereby. CONSTITUTION:A particulate substance comprising a refractory inorg. powder supporting a catalytically active substance is formed into an aqueous slurry along with an inorg. fibrous substance and one or more of dispersant selected from a group consisting of an alumina sol. a titania sol, a zirconia sol, a silica sol, a soluble boehmite and a soluble org. high-molecular compound. The aforementioned particulate substance is supported by the gas contact surface or gas contact part of a refractory three-dimensional structure in a protruded state using said slurry to prepare a catalyst for purifying exhaust gas. As the catalytically active substance, one containing one or more of a platinum group element consisting of platinum, rhodium and palladium and iron or cobalt is used.