Catalytic selective oxidation of light alkanes ; Valorisation d'alcanes légers par voie catalytique
Over the past few decades, selective oxidation of isobutane (IBAN) to methacrolein (MAC) and methacrylic acid (MAA) has received great interests both in the chemical industry and in fundamental research. The advantages of this reaction originate only from its low raw-materials' cost and reduced process complexity, but also from limiting the use of toxic reactants and the reduction of wastes. Successive studies and reports have shown that heteropolycompounds with Keggin structures (under the form of a partially neutralized acid to increase their stability) present the best catalytic behaviorfor isobutane conversion. This is due to their strong and tunable acidity and redox properties. In this work, Keggin-type heteropolyacids (HPAs) containing rubidium or cesium as counter cations have been prepared. Keggin-type polyoxometalates (POMs) as heterogeneous catalyst perform surface-type reaction, however the low surface area and low thermal stability of the bulk heteropolycompounds (HPCs) limit their applications. Therefore,supported Keggin-type HPCs were investigated as catalysts. More precisely the active phase Cs2H2PMo11VO40 (CsV1), Cs2.5H2.5PMo10V2O40 (CsV2),Rb2H2PMo11VO40 (RbV1) and Rb2.5H2.5PMo10V2O40 (RbV2) were supported on a commercial CARiACT SiO2 carrier, with various loadings of 10-50 wt.% to obtain high specific surface area. It was evidenced that the thermal stability and reducibility of the Keggin type HPAs were improved by supporting the active phase on SiO2. The textural properties, structural features, acidity and redox properties and the stability of the catalysts were studied using various techniques to establish correlations between the key properties of the samples and their catalytic performances. The results in catalyticperformance of isobutane to MAA and MAC showed that a well-balanced surface acid site density is necessary to get an efficient catalyst for isobutane conversion and MAA + MAC selectivity. Furthermore, the investigation of the catalytic performances not only focused on the ....
| Medienart: |
E-Book |
|---|
| Erscheinungsjahr: |
2021 |
|---|---|
| Erschienen: |
Erscheinungsort nicht ermittelbar: HAL CCSD ; 2021 |
| Sprache: |
Englisch |
|---|
| Beteiligte Personen: |
Zhang, Li [VerfasserIn] |
|---|---|
| Hochschulschrift: |
| Links: |
tel.archives-ouvertes.fr [kostenfrei] |
|---|
| Förderinstitution / Projekttitel: |
|
|---|
| PPN (Katalog-ID): |
1828091642 |
|---|
| LEADER | 01000cam a22002652 4500 | ||
|---|---|---|---|
| 001 | 1828091642 | ||
| 003 | DE-627 | ||
| 005 | 20230426192757.0 | ||
| 007 | cr uuu---uuuuu | ||
| 008 | 221202s2021 xx |||||o 00| ||eng c | ||
| 035 | |a (DE-627)1828091642 | ||
| 035 | |a (DE-599)KXP1828091642 | ||
| 040 | |a DE-627 |b ger |c DE-627 |e rakwb | ||
| 041 | |a eng | ||
| 100 | 1 | |a Zhang, Li |e verfasserin |4 aut | |
| 245 | 1 | 0 | |a Catalytic selective oxidation of light alkanes ; Valorisation d'alcanes légers par voie catalytique |
| 264 | 1 | |a [Erscheinungsort nicht ermittelbar] |b HAL CCSD |c 2021 | |
| 336 | |a Text |b txt |2 rdacontent | ||
| 337 | |a Computermedien |b c |2 rdamedia | ||
| 338 | |a Online-Ressource |b cr |2 rdacarrier | ||
| 502 | |b Dissertation |c HAL CCSD |d 2021 | ||
| 520 | |a Over the past few decades, selective oxidation of isobutane (IBAN) to methacrolein (MAC) and methacrylic acid (MAA) has received great interests both in the chemical industry and in fundamental research. The advantages of this reaction originate only from its low raw-materials' cost and reduced process complexity, but also from limiting the use of toxic reactants and the reduction of wastes. Successive studies and reports have shown that heteropolycompounds with Keggin structures (under the form of a partially neutralized acid to increase their stability) present the best catalytic behaviorfor isobutane conversion. This is due to their strong and tunable acidity and redox properties. In this work, Keggin-type heteropolyacids (HPAs) containing rubidium or cesium as counter cations have been prepared. Keggin-type polyoxometalates (POMs) as heterogeneous catalyst perform surface-type reaction, however the low surface area and low thermal stability of the bulk heteropolycompounds (HPCs) limit their applications. Therefore,supported Keggin-type HPCs were investigated as catalysts. More precisely the active phase Cs2H2PMo11VO40 (CsV1), Cs2.5H2.5PMo10V2O40 (CsV2),Rb2H2PMo11VO40 (RbV1) and Rb2.5H2.5PMo10V2O40 (RbV2) were supported on a commercial CARiACT SiO2 carrier, with various loadings of 10-50 wt.% to obtain high specific surface area. It was evidenced that the thermal stability and reducibility of the Keggin type HPAs were improved by supporting the active phase on SiO2. The textural properties, structural features, acidity and redox properties and the stability of the catalysts were studied using various techniques to establish correlations between the key properties of the samples and their catalytic performances. The results in catalyticperformance of isobutane to MAA and MAC showed that a well-balanced surface acid site density is necessary to get an efficient catalyst for isobutane conversion and MAA + MAC selectivity. Furthermore, the investigation of the catalytic performances not only focused on the ... | ||
| 856 | 4 | 0 | |u https://tel.archives-ouvertes.fr/tel-03710301 |x Verlag |z kostenfrei |
| 912 | |a GBV-BASE-ODISS | ||
| 912 | |a GBV_ILN_20 | ||
| 912 | |a ISIL_DE-84 | ||
| 912 | |a SYSFLAG_1 | ||
| 912 | |a GBV_KXP | ||
| 912 | |a SSG-OLC-PHA | ||
| 912 | |a GBV_ILN_2403 | ||
| 912 | |a ISIL_DE-LFER | ||
| 951 | |a BO | ||
| 980 | |2 20 |1 01 |x 0084 |b 4245856017 |h BASE-ODISS |y x |z 10-01-23 | ||
| 980 | |2 2403 |1 01 |x DE-LFER |b 4248093324 |c 00 |f --%%-- |d --%%-- |e n |j --%%-- |y l01 |z 14-01-23 | ||
| 981 | |2 20 |1 01 |x 0084 |r https://tel.archives-ouvertes.fr/tel-03710301 | ||
| 981 | |2 2403 |1 01 |x DE-LFER |r https://tel.archives-ouvertes.fr/tel-03710301 | ||
| 995 | |2 20 |1 01 |x 0084 |a BASE-ODISS | ||