Performance and characterization of MnOx-NiO catalysts for removing formaldehyde at room temperature. Issue 1 (July 2021) - Ding, Hua
Abstract: The effects of the hydrothermal co-precipitation factors of hydrothermal temperature, hydrothermal time, calcination temperature and calcination time on the crystal structure, microstructure, lattice defect and formaldehyde removal properties at indoor temperature of MnOx -NiO composite oxide catalysts were investigated by using the X-ray diffactiono (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and the catalytic activity testing apparatus. The results showed that the formaldehyde removal rate of the catalysts would increase first and then decrease with increasing in the hydrothermal temperature, or hydrothermal time, calcination temperature, calcination time. The maximum formaldehyde removal rate at indoor temperature is 95.57% with the best technology of the catalysts is as the following: 0.0125 mol potassium permanganate, 0.005 mol nickel nitrate, 5 ml sodium oxalate solution, 0.5 ml ammonia solution, hydrothermal 5 h at 130 °C and then calcination 5 h at 200 °C, the loose spherical accumulation specimen was composed of amorphous and crystal, and existed abundant Mn 4+ species and lattice oxygen on the catalyst surface.