Experimental and Theoretical Studies of Sonically Prepared Cu–Y, Cu–USY and Cu–ZSM-5 Catalysts for SCR deNOx

The objective of our study was to prepare Y-, USY- and ZSM-5-based catalysts by hydrothermal synthesis, followed copper active-phase deposition either conventional ion-exchange or ultrasonic irradiation. resulting materials were characterized XRD, BET, SEM, TEM, Raman, UV-Vis, monitoring ammonia nitrogen oxide sorption FT-IR Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). XRD data confirmed the purity structure Y/USY ZSM-5 zeolites. results indicated that highly porous acidic. metallic active phase found in form cations ion-exchanged zeolites nanoparticle metal oxides sonochemically prepared catalysts. latter showed full activity high stability SCR deNOx reaction. faujasite-based fully at 200–400 °C, whereas reached 100% 400–500 °C. Our situ DRIFTS experiments revealed Cu–O(NO) Cu–NH3 intermediates, also indicating role Brønsted sites formation NH4NO3. Furthermore, from experimental spectroscopic studies compared with DFT models. Overall, findings suggest two possible mechanisms for reaction, depending on method catalyst preparation (i.e., vs. irradiation).