Bifunctional Pt/Fe-ZSM-5 catalyst for xylene isomerization

The addition of iron to the synthesis of ZSM-5 catalysts (Si/Al=21) was studied in xylene isomerization reactions. Pt impregnation was conducted by partial vacuum impregnation on both the parent and Fe-ZSM-5. XRD, FE-SEM, ICP, BET, XPS, FT-IR, NH3-TPD, and TG analysis have been used to characterize the catalysts. Fe incorporation strongly decreased the weak acid sites and slightly reduced the strong acid sites. Reducing weak acidity led to lower coke formation and more catalytic stability in Fe-containing ZSM-5 catalysts. The presence of Pt on the Fe-supported ZSM-5 illustrated simultaneous high PX yield and high catalyst stability. (0.1 wt%)Pt/(0.4 wt%)Fe-ZSM-5 as an efficient and stable catalyst for xylene isomerization reactions demonstrated high PX yield (25.4 wt%), high EB conversion (61%) and low xylene loss (1.8%). (C) 2017 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.