Abstract: CaO modified CuZnAlZr mixed oxide catalysts were prepared by mechanical mixing and co-precipitation methods, and their catalytic performances for CO hydrogenation to higher alcohols were investigated using a continuous flow high-pressure fixed-bed micro-reactor. The catalysts were characterized by X-ray diffraction (XRD), N₂-adsorption-desorpotion, temperature-programmed reduction of H₂ (H₂-TPR), and temperature-programmed desorption of CO₂ (CO₂-TPD). The results showed that doping with CaO did not alter the textural properties of the catalyst, but increased the number of basic sites. Furthermore, the CaO-modified CuZnAlZr catalysts possessed both weak and medium strength basic sites, while unmodified CuZnAlZr catalyst possessed only weak basic sites. Catalytic performance, assessed by CO hydrogenation to C₂₊ alcohols, was improved in the CaO-doped CuZnAlZr catalyst relative to the undoped catalyst.

Key words: CaO modification, CuZnAlZr catalyst, Synthesis gas, Higher alcohol