{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T12:30:24Z","timestamp":1767357024327,"version":"3.48.0"},"reference-count":42,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T00:00:00Z","timestamp":1767312000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/MECI, Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Educa\u00e7\u00e3o, Ci\u00eancia e Inova\u00e7\u00e3o","award":["UID\/50006\/2025"],"award-info":[{"award-number":["UID\/50006\/2025"]}]},{"name":"CICECO-Aveiro Institute of Materials","award":["UIDB\/50011\/2020"],"award-info":[{"award-number":["UIDB\/50011\/2020"]}]},{"name":"CICECO-Aveiro Institute of Materials","award":["UIDP\/50011\/2020"],"award-info":[{"award-number":["UIDP\/50011\/2020"]}]},{"name":"CICECO-Aveiro Institute of Materials","award":["LA\/P\/0006\/2020"],"award-info":[{"award-number":["LA\/P\/0006\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Catalysts"],"abstract":"<jats:p>The development of sustainable catalysts from renewable resources is a key challenge for reducing the cost of industrial catalytic processes and waste valorization. In this work, low-cost heterogeneous active catalysts were prepared based on pyrolyzed forest residues, forming valuable porous support materials (Biochar) able to efficiently accommodate the highly active heteropolyacid HPW12. Further, magnetic functionality was incorporated in the novel catalytic materials by the impregnation of NiFe2O4. The resulting magnetic composites were characterized by FTIR-ATR, SEM-EDS, ICP-OES, BET, XRD, potentiometric titration and magnetometry. The novel HPW12@NiFe2O4@Biochar composites were able to valorize the glycerol to produce the fuel additive solketal with high conversion and high selectivity after only 3 h of reaction via acetalization reaction with acetone. The biochar catalytic composite prepared from cork presented higher pore size than the same prepared from forest biomass. This property was crucial to achieve the best conversion (89%) and the highest solketal selectivity (96%). Additionally, reusability capacity was verified, supporting the potential of the cork-pyrolyzed-based composites as potential low-cost catalytic material to produce fuel additives, such as solketal, under sustainable conditions. This may contribute one step further toward a future with greener energy, increasing the viability of biodiesel industry waste.<\/jats:p>","DOI":"10.3390\/catal16010052","type":"journal-article","created":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T12:23:44Z","timestamp":1767356624000},"page":"52","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Magnetic Polyoxometalate@Biochar Catalysts for Selective Acetalization of Glycerol into Fuel Additive"],"prefix":"10.3390","volume":"16","author":[{"given":"\u00d3scar","family":"Pellaumail","sequence":"first","affiliation":[{"name":"D\u00e9partement des Mat\u00e9riaux, \u00c9cole Polytechnique, Universitaire de Lille, Av. Paul Langevin, 59655 Villeneuve d\u2019Ascq, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0616-8985","authenticated-orcid":false,"given":"Lu\u00eds","family":"Dias","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE\u2014Laborat\u00f3rio Associado para a Qu\u00edmica Verde, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]},{"given":"Catarina N.","family":"Dias","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE\u2014Laborat\u00f3rio Associado para a Qu\u00edmica Verde, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6961-4911","authenticated-orcid":false,"given":"Sofia M.","family":"Bruno","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2260-1192","authenticated-orcid":false,"given":"Nuno J. O.","family":"Silva","sequence":"additional","affiliation":[{"name":"CICECO\u2014Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"CICECO\u2014Aveiro Institute of Materials, Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9647-6414","authenticated-orcid":false,"given":"Behrouz","family":"Gholamahmadi","sequence":"additional","affiliation":[{"name":"Department of Research and Development (R&D), Ibero Massa Florestal, S.A., 3720-584 Oliveira de Azem\u00e9is, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8984-0473","authenticated-orcid":false,"given":"Salete S.","family":"Balula","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE\u2014Laborat\u00f3rio Associado para a Qu\u00edmica Verde, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1952-8214","authenticated-orcid":false,"given":"F\u00e1tima","family":"Mirante","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE\u2014Laborat\u00f3rio Associado para a Qu\u00edmica Verde, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"286","DOI":"10.3390\/suschem2020017","article-title":"Continuous Valorization of Glycerol into Solketal: Recent Advances on Catalysts, Processes, and Industrial Perspectives","volume":"2","author":"Faria","year":"2021","journal-title":"Sustain. 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