Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst
Two quaternary ammonium catalysts based on the monovacant polyoxotungstate ([PW<sub>11</sub>O<sub>39</sub>]<sup>7−</sup>, abbreviated as PW<sub>11</sub>) were prepared and characterized. The desulfurization performances of the PW<sub>11</sub&g...
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| Format: | Article |
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MDPI AG
2020-10-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/25/21/4961 |
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| author | Fátima Mirante Baltazar de Castro Carlos M. Granadeiro Salete S. Balula |
| author_facet | Fátima Mirante Baltazar de Castro Carlos M. Granadeiro Salete S. Balula |
| author_sort | Fátima Mirante |
| collection | DOAJ |
| description | Two quaternary ammonium catalysts based on the monovacant polyoxotungstate ([PW<sub>11</sub>O<sub>39</sub>]<sup>7−</sup>, abbreviated as PW<sub>11</sub>) were prepared and characterized. The desulfurization performances of the PW<sub>11</sub>-based hybrids (of tetrabutylammonium and trimethyloctadecylammonium, abbreviated as TBA[PW<sub>11</sub>] and ODA[PW<sub>11</sub>], respectively), the corresponding potassium salt (K<sub>7</sub>PW<sub>11</sub>O<sub>39</sub>, abbreviated as KPW<sub>11</sub>) and the peroxo-compound (TBA-PO<sub>4</sub>[WO(O<sub>2</sub>)<sub>2</sub>], abbreviated as TBA[PW<sub>4</sub>]) were compared as catalysts for the oxidative desulfurization of a multicomponent model diesel (2000 ppm S). The oxidative desulfurization studies (ODS) were performed using solvent-free systems and aqueous H<sub>2</sub>O<sub>2</sub> as oxidant. The nature of the cation in the PW<sub>11</sub> catalyst showed to have an important influence on the catalytic performance. In fact, the PW<sub>11</sub>-hybrid catalysts showed higher catalytic efficiency than the peroxo-compound TBA[PW<sub>4</sub>], known as Venturello compound. TBA[PW<sub>11</sub>] revealed a remarkable desulfurization performance with 96.5% of sulfur compounds removed in the first 130 min. The reusability and stability of the catalyst were also investigated for ten consecutive ODS cycles without loss of activity. A treated clean diesel could be recovered without sulfur compounds by performing a final liquid/liquid extraction diesel/EtOH:H<sub>2</sub>O mixture (1:1) after the catalytic oxidative step. |
| first_indexed | 2024-03-10T15:18:59Z |
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| id | doaj.art-9b39af88777d4a5bae89835171fad017 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T15:18:59Z |
| publishDate | 2020-10-01 |
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| record_format | Article |
| series | Molecules |
| spelling | doaj.art-9b39af88777d4a5bae89835171fad0172023-11-20T18:39:01ZengMDPI AGMolecules1420-30492020-10-012521496110.3390/molecules25214961Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type CatalystFátima Mirante0Baltazar de Castro1Carlos M. Granadeiro2Salete S. Balula3LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, PortugalLAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, PortugalLAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, PortugalLAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, PortugalTwo quaternary ammonium catalysts based on the monovacant polyoxotungstate ([PW<sub>11</sub>O<sub>39</sub>]<sup>7−</sup>, abbreviated as PW<sub>11</sub>) were prepared and characterized. The desulfurization performances of the PW<sub>11</sub>-based hybrids (of tetrabutylammonium and trimethyloctadecylammonium, abbreviated as TBA[PW<sub>11</sub>] and ODA[PW<sub>11</sub>], respectively), the corresponding potassium salt (K<sub>7</sub>PW<sub>11</sub>O<sub>39</sub>, abbreviated as KPW<sub>11</sub>) and the peroxo-compound (TBA-PO<sub>4</sub>[WO(O<sub>2</sub>)<sub>2</sub>], abbreviated as TBA[PW<sub>4</sub>]) were compared as catalysts for the oxidative desulfurization of a multicomponent model diesel (2000 ppm S). The oxidative desulfurization studies (ODS) were performed using solvent-free systems and aqueous H<sub>2</sub>O<sub>2</sub> as oxidant. The nature of the cation in the PW<sub>11</sub> catalyst showed to have an important influence on the catalytic performance. In fact, the PW<sub>11</sub>-hybrid catalysts showed higher catalytic efficiency than the peroxo-compound TBA[PW<sub>4</sub>], known as Venturello compound. TBA[PW<sub>11</sub>] revealed a remarkable desulfurization performance with 96.5% of sulfur compounds removed in the first 130 min. The reusability and stability of the catalyst were also investigated for ten consecutive ODS cycles without loss of activity. A treated clean diesel could be recovered without sulfur compounds by performing a final liquid/liquid extraction diesel/EtOH:H<sub>2</sub>O mixture (1:1) after the catalytic oxidative step.https://www.mdpi.com/1420-3049/25/21/4961polyoxometalatepseudo-monophasic desulfurizationfuelsulfur oxidationhydrogen peroxide |
| spellingShingle | Fátima Mirante Baltazar de Castro Carlos M. Granadeiro Salete S. Balula Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst Molecules polyoxometalate pseudo-monophasic desulfurization fuel sulfur oxidation hydrogen peroxide |
| title | Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst |
| title_full | Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst |
| title_fullStr | Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst |
| title_full_unstemmed | Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst |
| title_short | Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst |
| title_sort | solvent free desulfurization system to produce low sulfur diesel using hybrid monovacant keggin type catalyst |
| topic | polyoxometalate pseudo-monophasic desulfurization fuel sulfur oxidation hydrogen peroxide |
| url | https://www.mdpi.com/1420-3049/25/21/4961 |
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