Effect of Calcination Parameters on Structural Properties and Activity of Carbon Nanofiber-Supported Cu/ZrO2 Catalyst in CO2 Hydrogenation to Methanol

The purpose of this work is to study the effect of calcination parameters (temperature and duration) on the structural properties and activity of carbon nanofiber-supported Cu/ZrO2 (Cu-ZrO2/CNF) catalyst. The catalyst was prepared by deposition precipitation method with fixed metal loading of 20wt% Cu and 5wt% Zr on CNF and calcined at temperature between 250-550˚C and duration between 3-4 hours. The catalyst structural properties were characterize using Thermal Gravimetric Analysis (TGA), BET analysis, X-ray diffraction (XRD) and Temperature Programmed Reduction (TPR). The performance of the catalysts were studied in a stirred reactor at feed ratio H2/CO2 = 3:1, Temperature = 443 K and Pressure =3.0 MPa for 3 hours. XRD studies revealed that the degree of crystallization of catalyst increased with increase of calcination temperature. BET analysis showed that the catalyst subjected to low calcination temperature has higher surface area. TPR analyses concluded that the reduction temperature for the catalyst is 350˚C and suggested that higher temperature and longer duration of calcination give more narrow peak which describe large CuO particle present on the catalyst surface. The highest yield of methanol, 38.67%, was achieved using the catalyst calcined at temperature 550˚C and duration of 4 hours.