SO2 adsorption on silica supported iridium
Journal article, 2017

The interaction of SO2 with Ir/SiO2 was studied by simultaneous in situ diffuse reflectance infrared Fourier transform spectroscopy and mass spectrometry, exposing the sample to different SO2 concentrations ranging from 10 to 50 ppm in the temperature interval 200–400 ◦C. Evidences of adsorptionof sulfur species in both absence and presence of oxygen are found. For a pre-reduced sample in the absence of oxygen, SO2 disproportionates such that the iridium surface is rapidly saturated with adsorbed S while minor amounts of formed SO3 may adsorb on SiO2. Adding oxygen to the feed leads to the oxidation of sulfide species that either (i) desorb as SO2 and/or SO3, (ii) remain at metal sites in the form of adsorbed SO2, or (iii) spillover to the oxide support and form sulfates (SO42−). Notably, significant formation of sulfates on silica is possible only in the presence of both SO2 and O2, suggesting that SO2 oxidation to SO3 is a necessary first step in the mechanism of formation of sulfates on silica. During the formation of sulfates, a concomitant removal/rearrangement of surface silanol groups is observed. Finally, the interaction of SO2 with Ir/SiO2 depends primarily on the temperature and type of gas components but only to a minor extent on the inlet SO2 concentration.

Author

Djamela Bounechada

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

David Philip Anderson

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Magnus Skoglundh

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Per-Anders Carlsson

Competence Centre for Catalysis (KCK)

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Journal of Chemical Physics

0021-9606 (ISSN) 1089-7690 (eISSN)

Vol. 146 8 084701- 084701

Competence Centre for Catalysis

ECAPS AB, 2014-01-01 -- 2017-12-31.

Chalmers, 2014-01-01 -- 2017-12-31.

Volvo Cars, 2014-01-01 -- 2017-12-31.

Scania CV AB, 2014-01-01 -- 2017-12-31.

Wärtsilä Finland, 2014-01-01 -- 2017-12-31.

Haldor Topsoe, 2014-01-01 -- 2017-12-31.

Swedish Energy Agency, 2014-01-01 -- 2017-12-31.

Volvo Group, 2014-01-01 -- 2017-12-31.

Time-resolved in situ methods for design of catalytic sites within sustainable chemistry

Swedish Research Council (VR), 2013-01-01 -- 2016-12-31.

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Materials Science

Subject Categories

Physical Chemistry

Materials Chemistry

DOI

10.1063/1.4976835

PubMed

28249452

More information

Latest update

10/28/2018