Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5
The Ir/Pt-HZSM5 with different iridium loading (0.3-1.0 wt%) was prepared by impregnation of iridium on Pt-HZSM5. The acidic properties of Ir/Pt- HZSM5 were studied by FTIR spectroscopy, while the activity of the catalysts was tested for n-pentane isomerization in a microcatalytic pulse reactor. The...
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IbnuSina Institute
2013
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author | Setiabudi, Herma Dina Teh, L. P. Abdul Jalil, Aishah |
author_facet | Setiabudi, Herma Dina Teh, L. P. Abdul Jalil, Aishah |
author_sort | Setiabudi, Herma Dina |
collection | ePrints |
description | The Ir/Pt-HZSM5 with different iridium loading (0.3-1.0 wt%) was prepared by impregnation of iridium on Pt-HZSM5. The acidic properties of Ir/Pt- HZSM5 were studied by FTIR spectroscopy, while the activity of the catalysts was tested for n-pentane isomerization in a microcatalytic pulse reactor. The IR results of adsorbed 2,6-lutidine showed that all catalysts possessed strong Brönsted and Lewis acid sites in the outgassing at 473 K and below. When Ir/Pt-HZSM5 was heated in hydrogen, protonic acid sites were formed with concomitant decrease of Lewis acid sites. An increase in iridium loading continuously decreased the Lewis and Brönsted acid sites and inhibited the formation of protonic acid sites induced by hydrogen. The formation of protonic acid sites induced by hydrogen was also confirmed by the formation of electron detected by ESR spectroscopy. Additionally for n-pentane isomerization, an increase in iridium loading decreased the yield of isopentane due to the inhibition in the formation of protonic acid sites via hydrogen spillover phenomenon.The Ir/Pt-HZSM5 with different iridium loading (0.3-1.0 wt%) was prepared by impregnation of iridium on Pt-HZSM5. The acidic properties of Ir/Pt- HZSM5 were studied by FTIR spectroscopy, while the activity of the catalysts was tested for n-pentane isomerization in a microcatalytic pulse reactor. The IR results of adsorbed 2,6-lutidine showed that all catalysts possessed strong Brönsted and Lewis acid sites in the outgassing at 473 K and below. When Ir/Pt-HZSM5 was heated in hydrogen, protonic acid sites were formed with concomitant decrease of Lewis acid sites. An increase in iridium loading continuously decreased the Lewis and Brönsted acid sites and inhibited the formation of protonic acid sites induced by hydrogen. The formation of protonic acid sites induced by hydrogen was also confirmed by the formation of electron detected by ESR spectroscopy. Additionally for n-pentane isomerization, an increase in iridium loading decreased the yield of isopentane due to the inhibition in the formation of protonic acid sites via hydrogen spillover phenomenon. |
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spelling | utm.eprints-478522017-01-31T07:37:30Z http://eprints.utm.my/47852/ Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5 Setiabudi, Herma Dina Teh, L. P. Abdul Jalil, Aishah QD Chemistry The Ir/Pt-HZSM5 with different iridium loading (0.3-1.0 wt%) was prepared by impregnation of iridium on Pt-HZSM5. The acidic properties of Ir/Pt- HZSM5 were studied by FTIR spectroscopy, while the activity of the catalysts was tested for n-pentane isomerization in a microcatalytic pulse reactor. The IR results of adsorbed 2,6-lutidine showed that all catalysts possessed strong Brönsted and Lewis acid sites in the outgassing at 473 K and below. When Ir/Pt-HZSM5 was heated in hydrogen, protonic acid sites were formed with concomitant decrease of Lewis acid sites. An increase in iridium loading continuously decreased the Lewis and Brönsted acid sites and inhibited the formation of protonic acid sites induced by hydrogen. The formation of protonic acid sites induced by hydrogen was also confirmed by the formation of electron detected by ESR spectroscopy. Additionally for n-pentane isomerization, an increase in iridium loading decreased the yield of isopentane due to the inhibition in the formation of protonic acid sites via hydrogen spillover phenomenon.The Ir/Pt-HZSM5 with different iridium loading (0.3-1.0 wt%) was prepared by impregnation of iridium on Pt-HZSM5. The acidic properties of Ir/Pt- HZSM5 were studied by FTIR spectroscopy, while the activity of the catalysts was tested for n-pentane isomerization in a microcatalytic pulse reactor. The IR results of adsorbed 2,6-lutidine showed that all catalysts possessed strong Brönsted and Lewis acid sites in the outgassing at 473 K and below. When Ir/Pt-HZSM5 was heated in hydrogen, protonic acid sites were formed with concomitant decrease of Lewis acid sites. An increase in iridium loading continuously decreased the Lewis and Brönsted acid sites and inhibited the formation of protonic acid sites induced by hydrogen. The formation of protonic acid sites induced by hydrogen was also confirmed by the formation of electron detected by ESR spectroscopy. Additionally for n-pentane isomerization, an increase in iridium loading decreased the yield of isopentane due to the inhibition in the formation of protonic acid sites via hydrogen spillover phenomenon. IbnuSina Institute 2013 Article PeerReviewed Setiabudi, Herma Dina and Teh, L. P. and Abdul Jalil, Aishah (2013) Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5. Malaysian Journal of Fundamental and Applied Sciences, 9 (1). pp. 10-15. ISSN 1823-626X |
spellingShingle | QD Chemistry Setiabudi, Herma Dina Teh, L. P. Abdul Jalil, Aishah Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5 |
title | Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5 |
title_full | Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5 |
title_fullStr | Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5 |
title_full_unstemmed | Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5 |
title_short | Effect of iridium loading on the formation of protonic acid sites over ir/pt-hzsm5 |
title_sort | effect of iridium loading on the formation of protonic acid sites over ir pt hzsm5 |
topic | QD Chemistry |
work_keys_str_mv | AT setiabudihermadina effectofiridiumloadingontheformationofprotonicacidsitesoverirpthzsm5 AT tehlp effectofiridiumloadingontheformationofprotonicacidsitesoverirpthzsm5 AT abduljalilaishah effectofiridiumloadingontheformationofprotonicacidsitesoverirpthzsm5 |