Document Type : Research Paper
Department of Petrochemical, Iran Polymer and Petrochemical Institute, (IPPI) Tehran, Iran
School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
Transformation of ethylbenzene can provide valuable isomers as a raw material for the petrochemical industry. This work explored the transformation of ethylbenzene (EB) over nanozeolite Y with the Si/Al ratio of 5. Fe ion exchange was carried out to modify the acidity of zeolites. The influence of platinum was investigated by the introduction of Pt-Al2O3. XRD, SEM, ICP, BET, FTIR, 27Al MAS NMR, NH3-TPD, and TG tests were applied for the characterization of physicochemical properties of prepared nanocatalysts. The slight decrease in the surface area of synthesized Fe-Y nanocatalysts indicated that the major part of iron was deposited in the catalyst structure. The addition of iron to the nanocatalyst structure resulted in increased strong acid sites and decreased weak acid sites. Reduction in weak acidity led to a lower coke formation rate and higher stability of FeY nanocatalysts. Results illustrated that the intensity of Lewis acidity decreased for all prepared nanocatalysts by increasing the iron content while the number of Bronsted acid sites increased. The addition of platinum-Al2O3 to the FeY nanocatalysts illustrated higher EB conversion and the same catalyst stability as FeY nanocatalysts. Nanozeolite Pt/Fe-Y composed of 0.1 wt.% platinum and 1.0 wt.% iron was obtained to be effective catalyst for EB transformation reaction. The prepared catalyst indicated adequate degree of EB conversion (61%) as well as 77.2% EB isomerization, 3.3% EB disproportionation, 1.4% EB dealkylation, 3.1% EB cracking, 14.8% EB hydrogenation and 0.2% EB transalkylation.