Formation of Dimethyl Carbonate on Nature Clay Supported Bimetallic Copper-Nickel Catalysts

Halloysite nanotubes supported Cu-Ni bimetallic catalysts were synthesized and applied to the direct formation of dimethyl carbonate (DMC) from methanol and CO2. Halloystite nanotubes (HNTs), K treated HNTs (KHNTs) and the synthesized catalysts were characterized by thermogravimetric and differential thermalgravimetric analysis (TG-DTA), temperature programmed reduction (TPR), X-ray photoelectron spectrum (XPS), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray powder diffraction (XRD), and temperature programmed desorption (TPD) techniques. The catalyst activities were evaluated in a continuous fixed-bed tubular microreactor under 1.2 MPa at 130 °C. The effects of the metal weight loadings on the catalytic performances and surface acid-base properties were studied. It was found that moderately acid-base balance on the catalysts surface were important for the DMC yield.