Regeneration of full-scale commercial honeycomb monolith catalyst (V ₂O ₅-WO ₃/TiO ₂) used in coal-fired power plant

An effective and applicable method for the regeneration of used commercial full-scale honeycomb monolith catalysts in China (V ₂O ₅-WO ₃/TiO ₂) is firstly reported. The de-ionized water and dilute sulfuric acid solution with a relatively low concentration (pH=2) are potent reagent to regenerated the catalysts used for about 30,000h in coal-fired power plant. All samples were systematically characterized by TEM, N ₂ adsorption/desorption, EDX, FT-IR and XPS techniques. The evaluation results reveal that the activity of the used catalysts can be obviously improved after regeneration processes. Moreover, the regenerated catalysts possess superior activity under different gas hourly space velocity (GHSV), and SO ₂ oxidation rate is lower than 1% in all cases. The regeneration method can remove the deposits, restore active sites and prevent nanoparticles aggregation as well as active phases leaching. Overall, these processes have promised as effective approaches for industrial V ₂O ₅-WO ₃/TiO ₂ catalysts regeneration.