Catalysts for controlling auto exhaust emissions including hydrocarbon, carbon monoxide, nitrogen oxides and hydrogen sulfide

摘要

A catalyst, which is capable of controlling not only HC, CO and NOx, but also H₂S emission from the tail pipe of catalytic converter-equipped automobiles, is made of noble metals promoted with ceria-rich rare earth oxides, preferably doubly promoted along with alkali metal oxides, and oxides of nickel and/or iron as an H₂S gettering ingredient. The oxides of nickel and/or iron are present in an H₂S gettering effective amount and in an amount up to 10 wt%. The alumina support can have additionally from 0 to 20% SiO₂ present.