Recycling of manganese ore desulfurization slag for preparation of low-temperature NH3-SCR catalyst with good scale-up production performance

Considering the synergistic carbon/pollution reduction and resource utilization, this study proposes recycling of manganese desulfurization slag to prepare low -temperature NH3 -SCR catalyst based on solid-state ion -exchange. The desulfurization slag was hydrothermally treated to be support under mild conditions, with the parent manganese oxide ore serving as active component. Hydrothermal treatment with a desulfurization slag to NaOH mass ratio of 1.0, at 100 degrees C for 10 h were actually cost-effective conditions for DS recycling. The catalyst with 13.6 wt% of Mn and activated at 450 degrees C for 2 h in air (MO3/DSH-450 -2) performed the best, with a NO conversion of 86.9% at 150 degrees C and 10000 h-1, and up to 92.6% at 175 degrees C. Hydrothermal treatment of DS, SSIE and calcination activation resulting in a rich surface acidity and lattice oxygen of MO3/DSH, coupled with better chemical state distribution of active metal sites, promoting the NH3 -SCR activity. The scale -up produced MO3/ DSH-G maintained 90.4% NOx conversion at 175 degrees C, showing good robustness, flexibility, and better sulfur/ water resistance. The development of MO3/DSH catalyst may make full use of natural manganese ore, is a typical coupling strategy for carbon -pollutant synergistic emission reduction and resource fully utilize.