Regeneration process of the SCR catalyst was investigated. Several methods such as the X-ray diffraction( XRD)
X-ray fluorescence( XRF)
X-ray photoelectron spectroscopy( XPS) and specific surface area analysis were employed to characterize the catalysts before and after the regeneration. Moreover
the regeneration effect was also tested on a laboratory bench with simulated flue gas. The results show that
cleaning using aeration or ultrasonic assisted dilute sulfuric acid was proved to be effective in eliminating the poisons and recovering the specific surface area
and the aeration way performed better. With the aid of cosolvent ethanolamine
ammonium vanadate aqueous solutions with different concentrations could be obtained and used as precursors for active material replenishment.After drying and calcination
the catalysts were replenished with vanadium oxide
and the NO conversion ratio could reach up to 92%. Cerium nitrate was an alternative for ammonium vanadate because of its excellent solubility in water. After the impregnating-drying-calcining process
the catalyst was regenerated with cerium oxide
thus the temperature window was extended and the NO conversion ratio was enhanced to 90% at most.