This review summarizes the synthesis, applications for the NH₃-SCR and methods for strengthening the water resistance and thermal stability of MOF catalysts.

Honeycomb cordierite-based Mn–Ce/Al₂O₃ catalysts were prepared by the impregnation method and used for low-temperature selective catalytic reduction (SCR) of NO_x with NH₃, with and without SO₂ and/or H₂O in a homemade fixed-bed tubular reactor. The catalyst reached nearly 80% NO_x conversion at 100 °C in the absence of SO₂. However, SO₂ reduces the catalytic activity (80% to 72%) of the honeycomb cordierite-based Mn–Ce/Al₂O₃ catalysts under identical conditions. This finding demonstrated that the catalyst exhibited high activity at low temperature and excellent SO₂ resistance in the presence of 50 ppm SO₂. The fresh and sulfated honeycomb cordierite-based Mn–Ce/Al₂O₃ catalysts were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), N₂ adsorption–desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry and differential thermal analysis (TG-DTA), and Fourier transform infrared (FT-IR) spectroscopy. Characterization results indicated that the deactivation by SO₂ was primarily the result of the deposition of ammonium hydrogen sulfate and sulfated CeO₂ on the catalyst surface during the SCR process. The formed sulfates depressed the catalytic activity via the blocking of pores and the occupation of active sites. Additionally, the competitive adsorption between SO₂ and NH₃ always decreased the catalytic activity.