Acrolein production from glycerol dehydration over amorphous V–P–N–C catalysts

Amorphous catalysts exhibit a plethora of oxygen vacancies, electron-rich active sites, and highly dispersed active centers, thereby yielding exceptional catalytic performance for multiple reactions. In this work, a series of amorphous V-P-N-C catalysts were synthesized using complexants and employed for catalyzing the glycerol dehydration reaction towards acrolein. Under optimized reaction conditions, the glycerol conversion reached 99.1% with an acrolein selectivity of 83.2% over the amorphous catalyst VPOC₆. The comprehensive characterization results of Raman, XPS, H₂-TPR, SEM, BET, and NH₃-TPD, demonstrated that the addition and decomposition of 1,6-diaminohexane leads to a transition from crystalline to amorphous state while preserving the fundamental vanadium-phosphorus oxide phases. It results in an active graphite-type nitrogen structure and an abundance of oxygen vacancies, which promote the target reaction by virtue of numerous medium acid sites on the catalyst surface.