Complete methane oxidation over Ba modified Pd/Al2O3: The effect of water vapor
Journal article, 2018

The effect on complete methane (CH 4 ) oxidation activity by an addition of up to 2 wt.% barium (Ba) promoter to alumina supported palladium (Pd/Al 2 O 3 , 2 wt.% Pd) was investigated. The catalyst samples were characterized with various techniques; temperature programmed oxidation (TPO), temperature programmed reduction with CH 4 (CH 4 -TPR), X-ray photoelectron spectroscopy (XPS), scanning transmission electron microscopy (STEM) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). Flow reactor was used to investigate the CH 4 oxidation activity in the presence and in the absence of water vapor and also to evaluate the possibility to regenerate the catalytic activity after water vapor exposure. The results from the TPO and the CH 4 -TPR experiments together with the XPS analysis gave no evidences for electronic promotion of the catalytic activity by addition of 0.5–2 wt.% Ba. This goes in line with the CH 4 conversion in dry gas condition, which was not affected by the Ba addition. However, we observed that an addition of Ba to Pd/Al 2 O 3 enhances the CH 4 oxidation activity in the presence of water vapor, hence mitigates the effect of water deactivation. Interestingly, it was also seen that after water vapor exposure, the CH 4 oxidation activity could be regenerated to greater extent for the Ba promoted samples, particularly for the regeneration temperatures of 500–600 °C. Our results clearly show that the support influences the water deactivation of the active palladium sites and that the addition of barium is beneficial for the catalyst regeneration.

Water deactivation

Regeneration

Methane oxidation

Pd

Ba

Author

Ida Friberg

Competence Centre for Catalysis (KCK)

Chalmers, Chemistry and Chemical Engineering, Chemical Technology, Chemical Reaction Engineering

Nadezda Sadokhina

Competence Centre for Catalysis (KCK)

Chalmers, Chemistry and Chemical Engineering, Chemical Technology, Chemical Engineering Design

Louise Olsson

Chalmers, Chemistry and Chemical Engineering, Chemical Technology

Competence Centre for Catalysis (KCK)

Applied Catalysis B: Environmental

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

Vol. 231 242-250

Areas of Advance

Transport

Subject Categories

Other Chemical Engineering

Other Chemistry Topics

Organic Chemistry

DOI

10.1016/j.apcatb.2018.03.003

More information

Latest update

12/3/2018