Advanced

Platinum on alumina, titania, and magnesia supports for the combustion of methanol in a waste gas with trace amount of ammonia

Hinz, A; Larsson, Per-Olof LU ; Skårman, Björn LU and Andersson, Arne LU (2001) In Applied Catalysis B: Environmental 34(2). p.161-178
Abstract
Pt (0.1 wt.%) on Al2O3, TiO2, and MgO supports were used for the low temperature combustion of methanol in both the absence and the presence of ammonia. Without NH3 in the gas the performance for the complete combustion decreases in the order Pt/MgO greater than or equal to Pt/TiO2 much greater than Pt/Al2O3 comparing a fixed amount of Pt surface area. In the presence of ammonia strong deactivation of Pt/Al2O3 and Pt/TiO2 is observed, whilst almost no deactivation of Pt/MgO occurs. The results are explained considering CO chemisorption and XPS measurements as well as the TPD profiles generated by adsorbed ammonia and methanol. A comparison of the TPD profiles of the N-2 which is formed from adsorbed ammonia on supported Pt and the support,... (More)
Pt (0.1 wt.%) on Al2O3, TiO2, and MgO supports were used for the low temperature combustion of methanol in both the absence and the presence of ammonia. Without NH3 in the gas the performance for the complete combustion decreases in the order Pt/MgO greater than or equal to Pt/TiO2 much greater than Pt/Al2O3 comparing a fixed amount of Pt surface area. In the presence of ammonia strong deactivation of Pt/Al2O3 and Pt/TiO2 is observed, whilst almost no deactivation of Pt/MgO occurs. The results are explained considering CO chemisorption and XPS measurements as well as the TPD profiles generated by adsorbed ammonia and methanol. A comparison of the TPD profiles of the N-2 which is formed from adsorbed ammonia on supported Pt and the support, respectively, reveals that Pt on Al2O3 and TiO2 interacts with the support surface, possibly through Pt-O-support bonding. The inference is supported by the XPS measurements showing that the Pt on Al2O3 and TiO2, as opposed to that on MgO, is slightly positively charged, making the interaction between ammonia and Pt stronger. Additional insight into the deactivation cause is obtained from TPD experiments with adsorbed methanol. These experiments reveal that on both Pt/Al2O3 and Pt/TiO2 there is competition between methanol and ammonia for adsorption sites, which is not the case on Pt/MgO. (C) 2001 Elsevier Science B.V. All rights reserved. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
methanol oxidation, Pt/Al2O3, Pt/TiO2, Pt/MgO, deactivation by ammonia, CO chemisorption, XRD, XPS, TEM, TPD
in
Applied Catalysis B: Environmental
volume
34
issue
2
pages
161 - 178
publisher
Elsevier
external identifiers
  • wos:000171902000007
  • scopus:0035813949
ISSN
0926-3373
DOI
10.1016/S0926-3373(01)00210-7
language
English
LU publication?
yes
id
16837c84-efab-46df-90d2-aaad1118b5a6 (old id 3917378)
date added to LUP
2013-07-03 14:21:55
date last changed
2018-01-07 09:47:04
@article{16837c84-efab-46df-90d2-aaad1118b5a6,
  abstract     = {Pt (0.1 wt.%) on Al2O3, TiO2, and MgO supports were used for the low temperature combustion of methanol in both the absence and the presence of ammonia. Without NH3 in the gas the performance for the complete combustion decreases in the order Pt/MgO greater than or equal to Pt/TiO2 much greater than Pt/Al2O3 comparing a fixed amount of Pt surface area. In the presence of ammonia strong deactivation of Pt/Al2O3 and Pt/TiO2 is observed, whilst almost no deactivation of Pt/MgO occurs. The results are explained considering CO chemisorption and XPS measurements as well as the TPD profiles generated by adsorbed ammonia and methanol. A comparison of the TPD profiles of the N-2 which is formed from adsorbed ammonia on supported Pt and the support, respectively, reveals that Pt on Al2O3 and TiO2 interacts with the support surface, possibly through Pt-O-support bonding. The inference is supported by the XPS measurements showing that the Pt on Al2O3 and TiO2, as opposed to that on MgO, is slightly positively charged, making the interaction between ammonia and Pt stronger. Additional insight into the deactivation cause is obtained from TPD experiments with adsorbed methanol. These experiments reveal that on both Pt/Al2O3 and Pt/TiO2 there is competition between methanol and ammonia for adsorption sites, which is not the case on Pt/MgO. (C) 2001 Elsevier Science B.V. All rights reserved.},
  author       = {Hinz, A and Larsson, Per-Olof and Skårman, Björn and Andersson, Arne},
  issn         = {0926-3373},
  keyword      = {methanol oxidation,Pt/Al2O3,Pt/TiO2,Pt/MgO,deactivation by ammonia,CO chemisorption,XRD,XPS,TEM,TPD},
  language     = {eng},
  number       = {2},
  pages        = {161--178},
  publisher    = {Elsevier},
  series       = {Applied Catalysis B: Environmental},
  title        = {Platinum on alumina, titania, and magnesia supports for the combustion of methanol in a waste gas with trace amount of ammonia},
  url          = {http://dx.doi.org/10.1016/S0926-3373(01)00210-7},
  volume       = {34},
  year         = {2001},
}