Effect of preparation conditions on the catalytic performance of Co/Ni catalysts for CO hydrogenation

Cobalt nickel oxide catalysts, prepared using co-precipitation procedure, were studied for the conversion of synthesis gas to light olefins. Specially, we studied the effect of a range of preparation variables, including the molar ratio of the [Co]/[Ni], pH, temperature and ageing time of the precipitation solution and finally, calcination conditions such as calcination temperature and calcination time. The catalyst containing a molar ratio of 80% Co and 20% Ni, aged for 150 min, precipitated at 50 °C and pH of 8.3 and calcined at 550 °C for 10 h performed optimally for the conversion of synthesis gas to light olefins. Characterization of both precursors and calcined catalysts was carried out using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) specific surface area measurements and thermal analysis methods including Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC).

► Preparation of Co–Ni catalyst using co-precipitation procedure. ► Evaluation of preparation variables: [Co]/[Ni] ratio, pH, T, ageing of precipitate and calcination conditions. ► Characterization of the catalysts at different stages of precursor, fresh and used calcined catalysts.