Effect of Cosolvent and Temperature on the Structures and Properties of Cu-MOF-74 in Low-temperature NH3-SCR

The novel Cu-MOF-74 materials were synthesized with various cosolvents at different temperatures by a solvent-thermal method and then developed as NO removal catalysts for low temperature selective catalytic reduction (SCR) with NH3. The physicochemical properties of catalyst samples were characterized by multiple techniques, such as N2 adsorption–desorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), temperature-programmed desorption (TPD), and X-ray photoelectron spectroscopy (XPS). The effects of cosolvent on the catalyst performances were systematically investigated. It was found that Cu-MOF-74-iso-80 catalyst showed the highest NH3-SCR activity, giving 97.8% NO conversion and 100% N2 selectivity at 230 °C. BET test results suggested that Cu-MOF-74 showed a larger specific surface area. Stronger NH3 adsorption ability was found, which could be beneficial for SCR at low temperature. The catalyst also showed better water resistance performance. The adverse effect of H2O added intermittently could be quickly eliminated when the water environment was removed.