| 摘要 |
PURPOSE:To efficiently purify exhaust gas discharged from the internal-combustion engine of an automobile, etc., especially exhaust gas contg. excess oxygen without using a reducing agent such as ammonia and to remove NOx with a catalyst for purification of exhaust gas excellent in durability at high temp. in the presence of steam. CONSTITUTION:An apatite compd. is incorporated into zeolite and one or more kinds of active metals or an alkaline earth metal and one or more kinds of active metals are incorporated into the resulting zeolite having a molar ratio of 1: >=15 between SiO2 and Al2O3 to obtain a catalyst. Exhaust gas contg. excess oxygen as well as NOx and hydrocarbon is brought into contact with the catalyst to remove the NOx. |
