A comparative study of the textural and catalytic properties of copper–zinc–aluminum catalysts synthesized by the carbonate and oxalate technologies is presented. The samples were characterized by physicochemical methods, including X-ray diffraction analysis, scanning electron microscopy, low-temperature nitrogen adsorption, and temperature-programmed reduction. The carbonate method led to the formation of a less developed porous structure with a specific surface area of 52 m2/g, pore volume of 0.067 cm3/g, and degree of copper dispersion of 3.84%, while the oxalate method gave a catalyst with significantly better textural characteristics: specific surface area of 140 m2/g, pore volume of 0.142 cm3/g, and degree of copper dispersion of 15%. Despite significant differences in their physicochemical properties, the catalytic activity of the catalysts differs only slightly; but the rate of methanol formation on the catalysts obtained using the carbonate technology is four times higher. The superior textural characteristics do not guarantee higher catalytic activity over the entire temperature range, and the low specific and active surface areas, as well as degree of dispersion, can reduce the service life of the catalyst. The results emphasize the importance of choosing the synthesis method to optimize the structural and functional properties of the catalysts; the influence of these properties on their activity and selectivity is demonstrated.
Rumyantsev et al. (Sun,) studied this question.