PREPARATION OF INTEGRAL STRUCTURE TYPE CATALYST FOR PURIFYING EXHAUST GAS

摘要

PURPOSE:To prepare the titled catalyst having excellent heat resistant durability and low temp. activity, by coating an integral structure type carrier with a slurry composition containing an activated alumina powder, a platinum group element compound and a cerium hydroxide powder. CONSTITUTION:An integral structure type carrier is coated with a slurry composition containing an activated alumina powder, a compound of at least one platinum group element and a cerium hydroxide powder. In this case, the support amount of the cerium hydroxide powder is set to 5-100g/l-catalyst as CeO2 and the particle size thereof is 0.1-0.8mum as a primary particle and 0.3-20mum as a secondary particle and the water content thereof is set to 40wt% or less. As a result, heat resistant durability is enhanced to a large extent as compared with a conventional catalyst using cerium nitrate and low temp. activity is also enhanced.