{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,11]],"date-time":"2026-04-11T07:02:04Z","timestamp":1775890924939,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,10,27]],"date-time":"2020-10-27T00:00:00Z","timestamp":1603756800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Two quaternary ammonium catalysts based on the monovacant polyoxotungstate ([PW11O39]7\u2212, abbreviated as PW11) were prepared and characterized. The desulfurization performances of the PW11-based hybrids (of tetrabutylammonium and trimethyloctadecylammonium, abbreviated as TBA[PW11] and ODA[PW11], respectively), the corresponding potassium salt (K7PW11O39, abbreviated as KPW11) and the peroxo-compound (TBA-PO4[WO(O2)2], abbreviated as TBA[PW4]) 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 H2O2 as oxidant. The nature of the cation in the PW11 catalyst showed to have an important influence on the catalytic performance. In fact, the PW11-hybrid catalysts showed higher catalytic efficiency than the peroxo-compound TBA[PW4], known as Venturello compound. TBA[PW11] 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:H2O mixture (1:1) after the catalytic oxidative step.<\/jats:p>","DOI":"10.3390\/molecules25214961","type":"journal-article","created":{"date-parts":[[2020,10,29]],"date-time":"2020-10-29T23:06:12Z","timestamp":1604012772000},"page":"4961","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1952-8214","authenticated-orcid":false,"given":"F\u00e1tima","family":"Mirante","sequence":"first","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]},{"given":"Baltazar","family":"de Castro","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0986-6607","authenticated-orcid":false,"given":"Carlos","family":"M. Granadeiro","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8984-0473","authenticated-orcid":false,"given":"Salete","family":"S. Balula","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1954","DOI":"10.1039\/c0gc00271b","article-title":"Aerobic oxidative desulfurization of benzothiophene, dibenzothiophene and 4,6-dimethyldibenzothiophene using an Anderson-type catalyst [(C18H37)2N(CH3)2]5[IMo6O24]","volume":"12","author":"Zhang","year":"2010","journal-title":"Green Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"590","DOI":"10.1016\/j.fuel.2014.09.083","article-title":"Temperature-responsive ionic liquid extraction and separation of the aromatic sulfur compounds","volume":"140","author":"Jiang","year":"2015","journal-title":"Fuel"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"608","DOI":"10.1016\/j.cej.2015.12.005","article-title":"Synthesis of supported SiW12O40-based ionic liquid catalyst induced solvent-free oxidative deep-desulfurization of fuels","volume":"288","author":"Xun","year":"2016","journal-title":"Chem. 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