Pilot-scale production of the low-temperature NH3-SCR catalyst with high industrial application prospects from natural zeolite and manganese oxide

In this study, a low-temperature NH₃ selective catalytic reduction (NH₃-SCR) catalyst with great industrial applicability was produced on a pilot scale using natural zeolite as the carrier and natural manganese oxide as the active component. The effects of activation temperature and nitric acid dosage on the mechanical strength and NH₃-SCR performance were discussed. The results demonstrated that the catalyst CMZ-10-600, prepared at a calcination temperature of 600°C with a 10.0 wt % nitric acid dosage, exhibited the best NH₃-SCR performance while meeting the mechanical strength requirements for industrial applications. The NO conversion ranged from 93.8% to 100.0%, and the N₂ selectivity varied between 78.0% and 100% at a gas hourly space velocity (GHSV) of 5000 h⁻¹ within the reaction temperature range of 150–250°C. The prepared catalysts were characterized using the scanning electron microscopy, x-ray powder diffraction, BET, NH₃-TPD, and x-ray photoelectron spectroscopy (XPS), which elucidated the effects of the preparation method on the catalyst strength, physicochemical properties, and the NH₃-SCR performance of the catalysts. The research results proved that the catalysts produced by this process exhibit good mechanical strength and catalytic properties, coupled with low raw material costs and a simple preparation technique, highlighting a promising prospect for industrial application.