Additively Manufactured Zirconia-Supported Indium Oxide Catalysts and Their Performance in Direct Methanol Synthesis

Abstract

In₂O₃/ZrO₂-based materials are emerging as candidates for the next generation of industrial catalysts for direct methanol synthesis. In this research, such catalysts were additively manufactured into two distinct geometries that exhibit different pressure drops and activity profiles, both among themselves and in comparison to extrudates. The monoliths produced were comprehensively characterized using a range of techniques, including gas sorption, X-ray diffraction, micro X-ray fluorescence, and Raman mapping, to verify their phase and chemical composition. Computational fluid dynamics was employed to simulate the gas flow through these structures, corroborating that the variations in the accessible surface area are the reason for changes in their performance. Furthermore, the postreaction characterization provides some insight into the catalysts’ degradation mechanisms under hydrogen-rich conditions, identifying the migration of indium oxide to the catalyst surface and pore blocking as possible causes of the loss of activity.