Boosted activity and water resistance towards catalytic ethyl acetate degradation over hierarchical MnO_x/meso-KZSM-5: K-incursion enriched active oxygen and Mn^4 + species

Developing efficient and economical catalysts with superior mineralization rate and water resistance for industrial volatile organic compounds (VOCs) low-temperature deep degradation is of great significance. Herein, hierarchical MnO_x/meso-KZSM-5 catalyst was engineered via a wetness impregnation approach, achieving 100 % CO₂ yield at 260 °C in ethyl acetate (EA) oxidation, over 100 °C lower than that of Mn/HZSM-5. Adsorbed oxygen species (O_ads) and Mn⁴⁺ respectively play vital roles in EA conversion to intermediates with long chain and deep degradation of intermediate with short chain. The presence of K reduces sites for H₂O adsorption and maintains the Mn⁴⁺ sites, thereby enhancing the water resistance and CO₂ yield simultaneously. Besides, the K species serves as an additional site for O₂ adsorption to compensate for the reduction in O_ads species due to the decrease in oxygen vacancies. Remarkably, the outstanding performance of monolithic Mn/meso-KZSM-5/cordierite in EA oxidation further extends the practical feasibility of above strategy.