Enhancing Pt-Ni/CeO₂ performances for ethanol reforming by catalyst supporting on high surface silica

In this paper, bimetallic Pt-Ni/CeO₂ catalysts supported over mesoporous silica were employed for ethanol reforming in the low-temperature range. In particular, catalyst behaviour was investigated under a H₂O/C₂H₅OH/N₂ as well as H₂O/C₂H₅OH/AIR mixture between 300 and 600 °C at different space velocities (10000–30000 h⁻¹). Ethanol conversion, for both steam (ESR) and oxidative steam reforming (OSR) reactions, was not affected by contact time decrease at T > 480 °C while at lower temperatures, the space velocity growth led to reduced C₂H₅OH conversion, more pronounced when tests were performed without O₂ co-feeding. Moreover, the catalysts showed high resistance to deactivation during reforming tests at 500 °C and 20000 h⁻¹: the improvement of active species dispersion, as a consequence of catalyst formulation enrichment by SiO₂ addition, resulted in lower carbon selectivity with respect to the SiO₂-free sample. However, the higher extent of coke gasification reaction for OSR further increased catalyst stability and total ethanol conversion was recorded for almost 3500 min, 1000 min more than ESR case.