Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions
Supported heteropoly acids are an interesting class of solid acid catalysts which possess flexible structure and super acidic properties essentially required for the oil-based biodiesel production. In this study, a series of catalysts containing 25 wt.% of heteropolytungstate (HPW) supported on vari...
Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2018-01-01
|
| Series: | Journal of Chemistry |
| Online Access: | http://dx.doi.org/10.1155/2018/7037461 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832564633931612160 |
|---|---|
| author | Ali Alsalme Aliyah A. Alsharif Hamda Al-Enizi Mujeeb Khan Saad G. Alshammari Mshari A. Alotaibi Rais Ahmad Khan Mohammed Rafiq H. Siddiqui |
| author_facet | Ali Alsalme Aliyah A. Alsharif Hamda Al-Enizi Mujeeb Khan Saad G. Alshammari Mshari A. Alotaibi Rais Ahmad Khan Mohammed Rafiq H. Siddiqui |
| author_sort | Ali Alsalme |
| collection | DOAJ |
| description | Supported heteropoly acids are an interesting class of solid acid catalysts which possess flexible structure and super acidic properties essentially required for the oil-based biodiesel production. In this study, a series of catalysts containing 25 wt.% of heteropolytungstate (HPW) supported on various clays or SiO2 were prepared, and their catalytic efficiency was evaluated for esterification of acetic acid with heptanol. The as-prepared catalysts were characterized by various techniques including FT-IR spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and BET. The catalytic efficiency of both bulk and supported HPW catalysts for the esterification activity strongly depends on the type of support and amount of catalyst; the bulk HPW catalyst and the catalyst supported by kaolinite with 25 wt.% of HPW exhibited highest activity. In order to study the effect of temperature on conversion, all the catalysts were subjected to different reaction temperatures. It was revealed that esterification activity of both bulk and supported HPW catalysts strongly depends upon the temperature variations of the reaction. Besides, the effect of leaching of active sites on the catalysts performance for biodiesel production was also evaluated by inductively coupled plasma studies (ICP). The kaolinite-supported catalyst (25% HPW/kaolinite) demonstrated higher amount of leaching which is also confirmed by the significant decrease in its catalytic activity when it is used for the second time. However, the higher activity demonstrated by HPW/kaolinite maybe because of some homogeneous reaction indicating a weak catalyst support interaction (WCSI) resulting in the leaching of the catalyst during the test. Furthermore, the effects of other reaction variables such as catalyst loading and reaction time on the conversion of acetic acid were also studied. |
| format | Article |
| id | doaj-art-c2ecb618b38a440da8b98b9f32bd8891 |
| institution | Kabale University |
| issn | 2090-9063 2090-9071 |
| language | English |
| publishDate | 2018-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | Journal of Chemistry |
| spelling | doaj-art-c2ecb618b38a440da8b98b9f32bd88912025-02-03T01:10:32ZengWileyJournal of Chemistry2090-90632090-90712018-01-01201810.1155/2018/70374617037461Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support InteractionsAli Alsalme0Aliyah A. Alsharif1Hamda Al-Enizi2Mujeeb Khan3Saad G. Alshammari4Mshari A. Alotaibi5Rais Ahmad Khan6Mohammed Rafiq H. Siddiqui7Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi ArabiaDepartment of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi ArabiaDepartment of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi ArabiaDepartment of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi ArabiaDepartment of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi ArabiaDepartment of Chemistry, College of Science and Humanities, Prince Sattam Bin Abdulaziz University, Alkharj, Saudi ArabiaDepartment of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi ArabiaDepartment of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi ArabiaSupported heteropoly acids are an interesting class of solid acid catalysts which possess flexible structure and super acidic properties essentially required for the oil-based biodiesel production. In this study, a series of catalysts containing 25 wt.% of heteropolytungstate (HPW) supported on various clays or SiO2 were prepared, and their catalytic efficiency was evaluated for esterification of acetic acid with heptanol. The as-prepared catalysts were characterized by various techniques including FT-IR spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and BET. The catalytic efficiency of both bulk and supported HPW catalysts for the esterification activity strongly depends on the type of support and amount of catalyst; the bulk HPW catalyst and the catalyst supported by kaolinite with 25 wt.% of HPW exhibited highest activity. In order to study the effect of temperature on conversion, all the catalysts were subjected to different reaction temperatures. It was revealed that esterification activity of both bulk and supported HPW catalysts strongly depends upon the temperature variations of the reaction. Besides, the effect of leaching of active sites on the catalysts performance for biodiesel production was also evaluated by inductively coupled plasma studies (ICP). The kaolinite-supported catalyst (25% HPW/kaolinite) demonstrated higher amount of leaching which is also confirmed by the significant decrease in its catalytic activity when it is used for the second time. However, the higher activity demonstrated by HPW/kaolinite maybe because of some homogeneous reaction indicating a weak catalyst support interaction (WCSI) resulting in the leaching of the catalyst during the test. Furthermore, the effects of other reaction variables such as catalyst loading and reaction time on the conversion of acetic acid were also studied.http://dx.doi.org/10.1155/2018/7037461 |
| spellingShingle | Ali Alsalme Aliyah A. Alsharif Hamda Al-Enizi Mujeeb Khan Saad G. Alshammari Mshari A. Alotaibi Rais Ahmad Khan Mohammed Rafiq H. Siddiqui Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions Journal of Chemistry |
| title | Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions |
| title_full | Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions |
| title_fullStr | Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions |
| title_full_unstemmed | Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions |
| title_short | Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions |
| title_sort | probing the catalytic efficiency of supported heteropoly acids for esterification effect of weak catalyst support interactions |
| url | http://dx.doi.org/10.1155/2018/7037461 |
| work_keys_str_mv | AT alialsalme probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions AT aliyahaalsharif probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions AT hamdaalenizi probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions AT mujeebkhan probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions AT saadgalshammari probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions AT mshariaalotaibi probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions AT raisahmadkhan probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions AT mohammedrafiqhsiddiqui probingthecatalyticefficiencyofsupportedheteropolyacidsforesterificationeffectofweakcatalystsupportinteractions |