Highly selective and stable Zn–Fe/ZSM-5 catalyst for aromatization of propane

Abstract

AbstractLight alkane aromatization for aromatic compound production, used in petrochemical industries is an attractive area of research. The effect of second metal co-impregnation was investigated in stabilizing zinc on ZSM-5 in aromatization of propane. HZSM-5 was modified with zinc and iron metal by co wet-impregnation and characterized using XRF, XRD, BET, N2-adsorption, FTIR, FTIR-Pyridine, SEM, TEM, H2-TPR and XPS. The effect of different loadings of Iron on Zn/ZSM-5 was investigated on acidity, aromatic yield, product distribution and aromatization performance. Performance test was conducted in a fixed bed reactor at 540 °C, one atmosphere. GHSV of 1200 mL/g-h. Co-impregnation of Zn with Fe improved the catalytic activity and aromatic yield for 10 h time on stream as compared to parent HZSM-5 and Zn/ZSM-5 of very low aromatic yield and propane conversion. Impregnation of Zn as the dehydrogenating metal on HZSM-5 steadily increased aromatic yield from 5% on HZSM-5 to 25% and was steadily dropped to 20% after 10 h TOS. The co-impregnation of iron of 1–3 wt% loading as the second metal for zinc stability with 2 wt% Zn on ZSM-5 improved propane conversion and aromatic yield to 55% for the 10 h TOS. This further enhanced aromatic product distribution and minimized light gases.