Characterization of Pt/γ-Al2O3 catalysts deactivated by hexamethyldisiloxane
Journal article, 2004

The deactivation of alumina supported platinum and iron catalysts by hexamethyldisiloxane (HMDS) exposure has been investigated. Three catalysts (Pt/Al2O3, Fe/Al2O3 and Fe/Pt/Al2O3) were prepared and the influence of short- and long-term deactivation on the activity for oxidation of ethyl acetate was studied. The catalysts were characterized using BET, ICP-AES, XPS, SEM and CO chemisorption. The deactivation was found to proceed by deposition of silicon-species in form of silicate (SixOy) that block the active sites on the surface of the catalysts. The silicon seems to rather attach to platinum and iron sites than to the alumina surface. The Pt/Al2O3 catalyst was moderately deactivated by HMDS even though the silicate was blocking almost the entire platinum surface. Adding iron to the catalyst increased the tolerance towards HMDS as fewer Pt sites were blocked for the Fe/Pt/Al2O3 sample. The deactivation of the two platinum containing samples was reversible since the silicate could partly be removed from the Pt sites by regeneration whereby most of the activity was restored. However, for the Fe/Al2O3 sample the deactivation was more severe and irreversible.

Platinum

Alumina

Iron

Silicon

Ethyl acetate oxidation

Hexamethyldisiloxane

Deactivation

Author

Karl Arnby

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Mohammad Rahmani

Amirkabir University of Technology

Vaxjo universitet

Mehri Sanati

Vaxjo universitet

Neil Cruise

Perstorp Formox

Annika Amberntsson Carlsson

Perstorp Formox

Magnus Skoglundh

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Applied Catalysis B: Environmental

0926-3373 (ISSN) 1873-3883 (eISSN)

Vol. 54 1 1-7

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology

Transport

Energy

Materials Science

Subject Categories

Chemical Engineering

Environmental Sciences

DOI

10.1016/j.apcatb.2004.06.007

More information

Created

10/7/2017