CATALYTIC ACTIVITY RECOVERY METHOD OF MANGANESE OXIDE CATALYST

Provided is a catalytic activity recovery method of a manganese oxide catalyst, an air-cleaning device using the same, air-cleaning system including the air-cleaning device, and an operation method of air-cleaning device by using the manganese oxide catalyst. The catalytic activity recovery method of a manganese oxide catalyst includes recovering the initial activity of a manganese Ni oxide catalyst by heating a manganese oxide catalyst which has been used to decompose ozone and of which activity is thus reduced by 10% or more compared to the initial ozone decomposition efficiency thereof, at the temperature of 80° C. to 250° C., so as to recover an ozone decomposition efficiency represented by Equation 1 to 90% or more of the initial ozone decomposition efficiency: Equation 1 Ozone decomposition efficiency (%)=[1−(concentration of ozone flowing out of the reactor)/(concentration of ozone flowing into the reactor)]×100