Synthesis and Characterization of Platinum Impregnated Zn-ZSM5 Nanocatalysts for Xylene Isomerization Reactions

The influence of zinc to the synthesis of ZSM-5 nanocatalysts (Si/Al = 24) was investigated in xylene isomerization reactions. Pt was doped through partial vacuum impregnation method on both the parent and Zn-ZSM-5. The synthesized nanocatalyst were characterized by ICP, BET, XRD, FE-SEM, XPS, Al-27 MAS NMR, FTIR, NH3-TPD, and TG analysis. The concentration of weak acid sites of ZSM-5 nanocatalyst slightly decreased while that of strong acid sites increased with the addition of Zn to the nano zeolite structure. Reducing weak acidity resulted in lower coke formation and remarkable catalytic stability in Zn-ZSM-5 nanocatalysts. The precence of Pt on the Zn-containing ZSM-5 illustrated simultaneous high PX yield and high catalytic stability. (0.1 wt%)Pt/(0.8 wt%) Zn-ZSM-5 as an active and stable nanocatalyst for xylene isomerization reactions demonstrated high PX yield (32.6 wt%), high level of EB conversion (68%) and low xylene loss (2.1%). [GRAPHICS] .