{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T06:54:13Z","timestamp":1774508053016,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,4,16]],"date-time":"2024-04-16T00:00:00Z","timestamp":1713225600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100016776","name":"CERENA","doi-asserted-by":"publisher","award":["UIDB\/04028\/2020"],"award-info":[{"award-number":["UIDB\/04028\/2020"]}],"id":[{"id":"10.13039\/100016776","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Catalysts"],"abstract":"<jats:p>Biodiesel from waste frying oil was produced via methanolysis using biochar-based catalysts prepared by carbonizing banana peels (350 \u00b0C and 400 \u00b0C) mixed with 20% (wt.) of alkali carbonates (Na, Li, or K). The catalysts exhibited a bi-functional character: acidic and basic. Raman spectroscopy confirmed the alkali\u2019s role in char graphitization, influencing morphology and oxygen content. Oxygenated surface sites acted as acidic sites for free fatty acid esterification, while alkali sites facilitated triglyceride transesterification. The best catalyst obtained by carbonization at 350 \u00b0C, without alkali modifier, led to 97.5% FAME by processing a waste frying oil with 1.2 mg KOH\/g oil acidity. Most of the studied catalysts yielded high-quality glycerin, allowing the significance of homogenous catalyzed processes to be discarded.<\/jats:p>","DOI":"10.3390\/catal14040266","type":"journal-article","created":{"date-parts":[[2024,4,17]],"date-time":"2024-04-17T08:22:44Z","timestamp":1713342164000},"page":"266","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Biodiesel Production over Banana Peel Biochar as a Sustainable Catalyst"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4585-470X","authenticated-orcid":false,"given":"Ana Paula","family":"Soares Dias","sequence":"first","affiliation":[{"name":"CERENA, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal"},{"name":"VALORIZA\u2014Research Centre for Endogenous Resource Valorization, Instituto Polit\u00e9cnico de Portalegre, 7300-555 Portalegre, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4522-6458","authenticated-orcid":false,"given":"Igor","family":"Pedra","sequence":"additional","affiliation":[{"name":"Escola Superior de Tecnologia do Barreiro, Instituto Polit\u00e9cnico de Set\u00fabal, Rua Am\u00e9rico da Silva Marinho, 2839-001 Lavradio, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-4709-348X","authenticated-orcid":false,"given":"\u00c9rica","family":"Salvador","sequence":"additional","affiliation":[{"name":"Escola Superior de Tecnologia do Barreiro, Instituto Polit\u00e9cnico de Set\u00fabal, Rua Am\u00e9rico da Silva Marinho, 2839-001 Lavradio, Portugal"}]},{"given":"Bruna","family":"Rijo","sequence":"additional","affiliation":[{"name":"VALORIZA\u2014Research Centre for Endogenous Resource Valorization, Instituto Polit\u00e9cnico de Portalegre, 7300-555 Portalegre, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7932-8062","authenticated-orcid":false,"given":"Manuel Francisco","family":"Costa Pereira","sequence":"additional","affiliation":[{"name":"CERENA, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6731-3832","authenticated-orcid":false,"given":"F\u00e1tima","family":"Serralha","sequence":"additional","affiliation":[{"name":"Escola Superior de Tecnologia do Barreiro, Instituto Polit\u00e9cnico de Set\u00fabal, Rua Am\u00e9rico da Silva Marinho, 2839-001 Lavradio, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6138-1172","authenticated-orcid":false,"given":"Isabel","family":"Nogueira","sequence":"additional","affiliation":[{"name":"MicroLab, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,16]]},"reference":[{"key":"ref_1","unstructured":"(2023, July 31). Biodiesel and Diesel Prices, 2019 to April 2022\u2014Charts\u2014Data & Statistics\u2014IEA, (n.d.). 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