Abstract
Ageing treatments were carried out on LaMn{sub 1-x}Mg{sub x}O{sub 3+{delta}} (x=0, 0.2, 0.5) catalysts for methane combustion to throw light on their deactivation mechanism in the presence of tetrahydrothiophene - used in Italy as odorant of natural gas - or directly in the presence of SO{sub 2}. Various characterisation techniques were used in concert: XRD, BET, TEM, SEM-EDS, FTIR, TPD, chemical analysis and atomic absorption. The effects of treatment temperature and exposure on catalytic activity were evaluated: exposure to 200ppmv SO{sub 2} at 800C for 24h causes a rather drastic deactivation of each LaMn{sub 1-x}Mg{sub x}O{sub 3} catalyst. Metal sulphate formation is the major responsible for deactivation. However, the extent of poisoning as well as the catalyst regenerability depends on the catalyst composition. The LaMn{sub 0.5}Mg{sub 0.5}O{sub 3} catalyst can in fact be regenerated completely by water leaching, while LaMn{sub 0.8}Mg{sub 0.2}O{sub 3} and LaMnO{sub 3} perovskites can be regenerated significantly only by leaching with aqueous NH{sub 3} solutions. An explanation of these results, also based on the values of activation energy for each fresh, poisoned and regenerated catalysts, is suggested and a mechanism for catalyst regeneration by water and NH{sub 4}OH solution is proposed.
Rosso, I;
Garrone, E;
Geobaldo, F;
Onida, B;
Saracco, G;
Specchia, V
[1]
- Dipartimento di Scienza dei Materiali e Ingegneria Chimica, Politecnico di Torino, Corso Duca degli Abruzzi, 24-10129 Turin (Italy)
Citation Formats
Rosso, I, Garrone, E, Geobaldo, F, Onida, B, Saracco, G, and Specchia, V.
Sulphur poisoning of LaMn{sub 1-x}Mg{sub x}O{sub 3} catalysts for natural gas combustion.
Netherlands: N. p.,
2001.
Web.
doi:10.1016/S0926-3373(00)00222-8.
Rosso, I, Garrone, E, Geobaldo, F, Onida, B, Saracco, G, & Specchia, V.
Sulphur poisoning of LaMn{sub 1-x}Mg{sub x}O{sub 3} catalysts for natural gas combustion.
Netherlands.
https://doi.org/10.1016/S0926-3373(00)00222-8
Rosso, I, Garrone, E, Geobaldo, F, Onida, B, Saracco, G, and Specchia, V.
2001.
"Sulphur poisoning of LaMn{sub 1-x}Mg{sub x}O{sub 3} catalysts for natural gas combustion."
Netherlands.
https://doi.org/10.1016/S0926-3373(00)00222-8.
@misc{etde_20149233,
title = {Sulphur poisoning of LaMn{sub 1-x}Mg{sub x}O{sub 3} catalysts for natural gas combustion}
author = {Rosso, I, Garrone, E, Geobaldo, F, Onida, B, Saracco, G, and Specchia, V}
abstractNote = {Ageing treatments were carried out on LaMn{sub 1-x}Mg{sub x}O{sub 3+{delta}} (x=0, 0.2, 0.5) catalysts for methane combustion to throw light on their deactivation mechanism in the presence of tetrahydrothiophene - used in Italy as odorant of natural gas - or directly in the presence of SO{sub 2}. Various characterisation techniques were used in concert: XRD, BET, TEM, SEM-EDS, FTIR, TPD, chemical analysis and atomic absorption. The effects of treatment temperature and exposure on catalytic activity were evaluated: exposure to 200ppmv SO{sub 2} at 800C for 24h causes a rather drastic deactivation of each LaMn{sub 1-x}Mg{sub x}O{sub 3} catalyst. Metal sulphate formation is the major responsible for deactivation. However, the extent of poisoning as well as the catalyst regenerability depends on the catalyst composition. The LaMn{sub 0.5}Mg{sub 0.5}O{sub 3} catalyst can in fact be regenerated completely by water leaching, while LaMn{sub 0.8}Mg{sub 0.2}O{sub 3} and LaMnO{sub 3} perovskites can be regenerated significantly only by leaching with aqueous NH{sub 3} solutions. An explanation of these results, also based on the values of activation energy for each fresh, poisoned and regenerated catalysts, is suggested and a mechanism for catalyst regeneration by water and NH{sub 4}OH solution is proposed.}
doi = {10.1016/S0926-3373(00)00222-8}
journal = []
issue = {1-2}
volume = {30}
journal type = {AC}
place = {Netherlands}
year = {2001}
month = {Feb}
}
title = {Sulphur poisoning of LaMn{sub 1-x}Mg{sub x}O{sub 3} catalysts for natural gas combustion}
author = {Rosso, I, Garrone, E, Geobaldo, F, Onida, B, Saracco, G, and Specchia, V}
abstractNote = {Ageing treatments were carried out on LaMn{sub 1-x}Mg{sub x}O{sub 3+{delta}} (x=0, 0.2, 0.5) catalysts for methane combustion to throw light on their deactivation mechanism in the presence of tetrahydrothiophene - used in Italy as odorant of natural gas - or directly in the presence of SO{sub 2}. Various characterisation techniques were used in concert: XRD, BET, TEM, SEM-EDS, FTIR, TPD, chemical analysis and atomic absorption. The effects of treatment temperature and exposure on catalytic activity were evaluated: exposure to 200ppmv SO{sub 2} at 800C for 24h causes a rather drastic deactivation of each LaMn{sub 1-x}Mg{sub x}O{sub 3} catalyst. Metal sulphate formation is the major responsible for deactivation. However, the extent of poisoning as well as the catalyst regenerability depends on the catalyst composition. The LaMn{sub 0.5}Mg{sub 0.5}O{sub 3} catalyst can in fact be regenerated completely by water leaching, while LaMn{sub 0.8}Mg{sub 0.2}O{sub 3} and LaMnO{sub 3} perovskites can be regenerated significantly only by leaching with aqueous NH{sub 3} solutions. An explanation of these results, also based on the values of activation energy for each fresh, poisoned and regenerated catalysts, is suggested and a mechanism for catalyst regeneration by water and NH{sub 4}OH solution is proposed.}
doi = {10.1016/S0926-3373(00)00222-8}
journal = []
issue = {1-2}
volume = {30}
journal type = {AC}
place = {Netherlands}
year = {2001}
month = {Feb}
}