Hydrothermal Synthesis of Zn-ZSM5 Catalyst for xylene isomerizationHydrothermal Synthesis of Zn-ZSM5 Catalyst for xylene isomerization

The addition of Zinc to the synthesis of ZSM-5 catalysts (Si/Al=21) was studied in xylene isomerization reactions. Physicochemical characteristics of the prepared catalysts were evaluated by XRD, BET, SEM, FTIR, NH3-TPD and TG analyses. Zn incorporation strongly increased the strong acid (Brønsted) sites and reduced the weak acidity (Lewis). Higher strong acidity led to higher PX yield and Lower weak acidity led to lower coke formation and more catalytic stability. (0.5 wt.%)Zn-ZSM-5 as an efficient and stable catalyst for xylene isomerization reactions demonstrated high PX yield (18.5 wt.%), high EB conversion (43.6%) and low xylene loss (3.3 %).