Steam reforming of aromatics mixture as a model tar over Ni/Al2O3 structured catalyst

Abstract

This study assessed a Ni/Al₂O₃ structured catalyst for steam reforming of toluene (SR-T) and naphthalene (SR-N) mixture feeds (SR-TN). The catalyst achieved around 100% conversion for SR-T and SR-N in a 10-hour reaction but experienced notable deactivation in the SR-TN system over 3 hours. Post-SR-TN, the catalyst showed higher coke deposition than after SR-T and SR-N, possibly explaining the varied deactivation. The impact of reaction temperature and catalyst weight-to-flow rate ratio (W/F_total) was explored, revealing that higher temperature and W/F_total ratio increased catalyst life and reduced coke deposition. Stable performance was observed for 50 hours under optimal conditions, exhibiting remarkable durability in steam reforming of model tar compounds. Characterization of deposited coke using field-emission scanning electron microscopy (FE-SEM) and Raman spectroscopy revealed lower crystallinity in the SR-TN system, suggesting a potential link to reforming activity decrease.