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Acetone transformation over PtSn/H[A1]ZSM5 catalysts

Abstract:

A study was carried out on the reaction of acetone transformation over bifunctional monometallic (Pt/H[A1]ZSM5, Sn,H[A1]ZSM5) and bimetallic (PtSn/H[A1]ZSM5) catalysts with variation of their tin atomic fraction (X Sn = number of Sn moles/number of Sn moles + number of Pt moles). The solids prepared were analyzed by means of X-ray diffraction (XRD), nitrogen adsorption at - 196 °C, chemical analysis through inductive coupled plasma-atomic emission spectroscopy (ICP-AES) technique, energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), electronic paramagnetic resonance (EPR), transmission electronic microscopy (TEM), and by means of test reaction of toluene hydrogenation. Acetone transformation was carried out at 160°C, under atmosphere pressure, at an acetone/hydrogen molar ratio of 3 and varying WHSV. The results obtained show a sensitive variation in the catalytic properties as XSn is varied in the series of PtSn/H[A1] ZSM5 catalysts prepared; these changes are attributed to the presence of effects of the electronic and geometric type, which would be a consequence of the formation of a Pt-Sn alloy and probably of the phenomenon of decoration of platinum particles, which is evidenced from the evaluation of the solids by means of XPS and EPR. © 2003 Elsevier B.V. All rights reserved.