Synergy of 3D, porous supports and surface alkalinity tendency in Cu/ZnO catalysts for methanol steam reforming

Abstract

The growing recognition of hydrogen as a strategic energy carrier has increased the need for efficient lowtemperature processes. Methanol steam reforming (MSR) is promising due to its mild operating conditions. Packed-bed reactors are widely used; however, achieving high conversion and selectivity is difficult because of heat and mass transfer limitations and poor reactant-catalyst contact, often requiring higher temperatures or alternative designs. This work addresses these challenges by developing three-dimensional, porous supports with controlled Ca modification. Zeolite- and kaolin-based supports were prepared by wet granulation and modified with different Ca(OH)2 loadings. Moderate Ca addition promoted CaO formation and improved porosity, whereas excessive loading reduced it, impairing performance. Z-HP-15Ca@Cu/ZnO showed the best zeolite performance, while K-HP-10Ca@Cu/ZnO was optimal for kaolin. Statistical analysis confirmed higher conversion for zeolitebased catalysts. Overall, this strategy couples Ca-derived surface species with support porosity to achieve high MSR performance at low temperatures.