N2o decomposition catalyst

A catalyst comprising:

• a support containing SiO2 and Al2O3;
• and
• an iron element supported on the support,
• wherein in a TPD spectrum, a ratio of a pyridine desorption amount at a peak top present in a range of 150° C. or higher and lower than 450° C. to a pyridine desorption amount at a peak top present in a range of 450° C. or higher and 800° C. or lower is more than 1, and
• the catalyst is configured to promote a decomposition reaction of nitrous oxide or a decomposition reaction of nitrous oxide and nitric oxide.

A catalyst comprising:

• a support containing SiO2 and Al2O3;
• and
• an iron element supported on the support,
• wherein in a TPD spectrum, a ratio of a total amount of pyridine desorbed in a range of 150° C. or higher and lower than 450° C. to a total amount of pyridine desorbed in a range of 450° C. or higher and 800° C. or lower is 0.9 or more, and
• the catalyst is configured to promote a decomposition reaction of nitrous oxide or a decomposition reaction of nitrous oxide and nitric oxide.

A catalyst comprising:

• a support containing SiO2 and Al2O3;
• and
• an iron element supported on the support,
• wherein in a TPD spectrum, a temperature at a peak top in a range of 450° C. or higher and 800° C. or lower is 490° C. or higher and 650° C. or lower, and
• the catalyst is configured to promote a decomposition reaction of nitrous oxide or a decomposition reaction of nitrous oxide and nitric oxide.

A catalyst comprising:

• a support containing SiO2 and Al2O3;
• and
• an iron element supported on the support,
• wherein a saturated adsorption amount of pyridine is 100 μmol or more per 1 g of the catalyst, and
• the catalyst is configured to promote a decomposition reaction of nitrous oxide or a decomposition reaction of nitrous oxide and nitric oxide.

A catalyst comprising:

• a support containing SiO2 and Al2O3;
• and
• an iron element supported on the support,
• wherein a crystallite size is 20 nm or more, and
• the catalyst is configured to promote a decomposition reaction of nitrous oxide or a decomposition reaction of nitrous oxide and nitric oxide.

A catalyst comprising:

• an organic structure-directing agent (OSDA)-free zeolite;
• and
• an iron element supported on the organic structure-directing agent (OSDA)-free zeolite,
• the catalyst is configured to promote a decomposition reaction of nitrous oxide or a decomposition reaction of nitrous oxide and nitric oxide.