Benefits of mesopores in nanocristalline Pd/SnO2 catalysts for nitrate hydrogenation

Abstract

Mesoporous nanocristalline SnO2 supports were synthesized by a modified sol-gel method starting from SnCl2·2H2O and citric acid at pH 2.0 and 9.5. Noble metal was introduced via wet impregnation using PdCl2 as active phase precursor. Catalysts activities in water denitration were correlated with their textural, structural and morphological properties using LTNA (BET), XRD and SEM/EDS analysis. Lower pH value during the catalyst synthesis resulted in a final material characterized with more developed porosity and higher surface area. Although both catalysts turned out to be tailored from nanoscale crystallites, higher pore fraction of mesopores resulting from the synthesis in acidic conditions, was found to be responsible for superior catalytic behavior.

Keywords

• nanostructured Pd/SnO2
• mesopores
• water denitration