{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T20:26:57Z","timestamp":1770755217566,"version":"3.50.0"},"reference-count":44,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2023,11,3]],"date-time":"2023-11-03T00:00:00Z","timestamp":1698969600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union","award":["POCI-01-0145-FEDER-031983"],"award-info":[{"award-number":["POCI-01-0145-FEDER-031983"]}]},{"name":"European Union","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}]},{"name":"Portuguese national funds","award":["POCI-01-0145-FEDER-031983"],"award-info":[{"award-number":["POCI-01-0145-FEDER-031983"]}]},{"name":"Portuguese national funds","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Glycerol is the main residue in the biodiesel production industry; therefore, their valorization is crucial. The acetalization of glycerol toward fuel additives such as solketal (2,2-dimethyl-1,3-dioxolan-4-methanol) is of high interest, promoting circular economy since it can be added to biodiesel or even fossil diesel to improve their quality and efficiency. Straightforward-prepared metal\u2013organic framework (MOF) materials of the MOF-808 family were applied to the valorization of glycerol for the first time. In particular, MOF-808(Hf) was revealed to be an effective heterogeneous catalyst to produce solketal under moderate conditions: a small amount of the MOF material (only 4 wt% of glycerol), a 1:6 ratio of glycerol\/acetone, and a temperature of 333 K. The high efficiency of MOF-808(Hf) was associated with the high amount of acid centers present in its structure. Furthermore, its structural characteristics, such as window opening cavity size and pore diameters, were shown to be ideal for reusing this material for at least ten consecutive reaction cycles without losing activity (conversion &gt; 90% and selectivity &gt; 98%). Remarkably, it was not necessary to wash or activate the MOF-808(Hf) catalyst between cycles (no pore blockage occurred), and it maintained structural integrity after ten cycles, confirming its ability to be a sustainable heterogeneous catalyst for glycerol valorization.<\/jats:p>","DOI":"10.3390\/ma16217023","type":"journal-article","created":{"date-parts":[[2023,11,3]],"date-time":"2023-11-03T02:41:56Z","timestamp":1698979316000},"page":"7023","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["MOF-808 as an Efficient Catalyst for Valorization of Biodiesel Waste Production: Glycerol Acetalization"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1952-8214","authenticated-orcid":false,"given":"F\u00e1tima","family":"Mirante","sequence":"first","affiliation":[{"name":"LAQV\/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6888-4215","authenticated-orcid":false,"given":"Pedro","family":"Leo","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"},{"name":"Department of Chemical and Environmental Technology, Universidad Rey Juan Carlos, Calle Tulip\u00e1n s\/n, 28933 M\u00f3stoles, Spain"}]},{"given":"Catarina N.","family":"Dias","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9229-1412","authenticated-orcid":false,"given":"Lu\u00eds","family":"Cunha-Silva","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8984-0473","authenticated-orcid":false,"given":"Salete S.","family":"Balula","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1016\/j.accre.2018.12.003","article-title":"Contributions of natural systems and human activity to greenhouse gas emissions","volume":"9","author":"Yue","year":"2018","journal-title":"Adv. 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