- High durable Pd-Rh three way catalyst for NOx reduction

摘要

PURPOSE: A method for manufacturing high durable Pd-Rh three way catalyst for NOx reduction is provided to improve heat-resistance and purifying efficiency, compared with conventional Pd-Rh three way catalyst containing only bulk CeO2. In this method, (Ce-Zr)O2 is added to improve heat-resistance of three way catalyst, and PrO2 is added to improve purifying efficiency of nitrogen oxide. The catalyst is used as catalyst for purifying exhaust gas emitted from vehicle and chemical industry. CONSTITUTION: According to the method, the high durable Pd-Rh three way catalyst is made by the following steps: (i) supporting 100 parts by weight of Al2O3 with 1-5 parts by weight of palladium and 0.1-1 parts by weight of rhodium, followed by reduction; (ii) reacting the Pd-Rd supported alumina with 5-10 parts by weight of cerium oxide; 18-27 parts by weight of cerium-zirconium composite oxides; 3-10 parts by weight of praseodymium oxide; 5-6 parts by weight of barium oxide and 1-2 parts by weight of lanthanum oxide.