초록 ▼

A NOx removal catalyst resistant to high temperatures, comprising an activated alumina wherein the specific surface area measured by the nitrogen adsorption method is 120 m2/g or more, the bulk density measured by the mercury porosimetry is 0.60 g/cm3 or more, and the skeleton density measured by th

A NOx removal catalyst resistant to high temperatures, comprising an activated alumina wherein the specific surface area measured by the nitrogen adsorption method is 120 m2/g or more, the bulk density measured by the mercury porosimetry is 0.60 g/cm3 or more, and the skeleton density measured by the mercury porosimetry is 1.80 g/cm3 or less and silver carried on said activated alumina. Then said catalyst or a structure having said catalyst coated on a substrate is brought in contact with exhaust gas from an internal combustion engine that is operated at a lean fuel/air ratio, such as a lean-burn engine, NOx can be removed efficiently within a quite short contact time.

대표청구항 ▼

A method of removing NOx from exhaust gas containing reducing components and oxidizing components including NOx from an internal combustion engine which is operated at a fuel lean air/fuel ratio, said oxidizing components being present in an amount more than the stoichiometric amount required for co

A method of removing NOx from exhaust gas containing reducing components and oxidizing components including NOx from an internal combustion engine which is operated at a fuel lean air/fuel ratio, said oxidizing components being present in an amount more than the stoichiometric amount required for completely oxidizing said reducing components, which method comprises bringing said exhaust gas into contact with a NOx removal catalyst, wherein the NOx removal catalyst comprises an activated alumina wherein the specific surface area measured by the nitrogen adsorption method is 120 m2/g or more, the bulk density measured by the mercury porosimetry is 0.60 g/cm3 or more, and the skeleton density measured by the mercury porosimetry is 1.80 g/cm3 or less and silver carried on said activated alumina under conditions effective for the removal of NOx.