{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T11:28:04Z","timestamp":1786966084232,"version":"build-2736575974"},"reference-count":43,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T00:00:00Z","timestamp":1786924800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The sustainable utilization of post-consumer plant biomass as a precursor for functional carbon materials has attracted increasing attention as an environmentally friendly approach to heterogeneous catalyst development. In this study, the aerial parts of Pelargonium zonale were converted into activated carbons by chemical activation with KOH at carbonization temperatures of 750, 800, and 850 \u00b0C. The obtained materials were comprehensively characterized using N2 adsorption\u2013desorption, XRD, FTIR, UV\u2013Vis spectroscopy, XRF, and SEM. Increasing the carbonization temperature promoted pore development, resulting in activated carbons with a maximum specific surface area of 1578 m2 g\u22121 and a total pore volume of 0.751 cm3 g\u22121. The catalytic performance of the obtained materials was evaluated in the oxidation of geraniol. No direct correlation between the textural properties of the activated carbons and their catalytic performance was observed, suggesting that catalytic behaviour results from the combined effect of several physicochemical properties. Optimization of the reaction conditions demonstrated that catalytic performance depended on the combined influence of reaction temperature, catalyst amount, reaction time, and catalyst properties. Under the optimized reaction conditions (110 \u00b0C, 0.5 wt% catalyst, and 360 min), the highest geraniol conversion (37 mol%) was achieved over CP_KOH_850. Kinetic modelling confirmed that geraniol oxidation proceeds through a complex network of parallel and consecutive reactions leading to the formation of citral, 2,3-epoxygeraniol, 2,3-epoxycitral, and other oxidation products. These findings demonstrate that waste Pelargonium zonale biomass is a promising renewable precursor for the preparation of functional carbon materials for heterogeneous catalytic applications.<\/jats:p>","DOI":"10.3390\/ma19163468","type":"journal-article","created":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T11:00:05Z","timestamp":1786964405000},"page":"3468","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Pelargonium zonale as a Source of Active Catalysts for the Oxidation of Geraniol with Oxygen"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3345-0644","authenticated-orcid":false,"given":"Sylwia","family":"Gajewska","sequence":"first","affiliation":[{"name":"Faculty of Chemical Technology and Engineering, Department of Catalytic and Sorbent Materials Engineering, West Pomeranian University of Technology in Szczecin, Piast\u00f3w Ave. 42, 71-065 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0070-5241","authenticated-orcid":false,"given":"Joanna","family":"Siemak","sequence":"additional","affiliation":[{"name":"Faculty of Chemical Technology and Engineering, Department of Catalytic and Sorbent Materials Engineering, West Pomeranian University of Technology in Szczecin, Piast\u00f3w Ave. 42, 71-065 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9713-259X","authenticated-orcid":false,"given":"Agnieszka","family":"Wr\u00f3blewska","sequence":"additional","affiliation":[{"name":"Faculty of Chemical Technology and Engineering, Department of Catalytic and Sorbent Materials Engineering, West Pomeranian University of Technology in Szczecin, Piast\u00f3w Ave. 42, 71-065 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6415-3178","authenticated-orcid":false,"given":"Luis A.","family":"Gallego-Villada","sequence":"additional","affiliation":[{"name":"Laboratory of Industrial Chemistry and Reaction Engineering, Johan Gadolin Process Chemistry Centre, \u00c5bo Akademi University, Henriksgatan 2, 20500 Turku, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9182-6550","authenticated-orcid":false,"given":"Beata","family":"Michalkiewicz","sequence":"additional","affiliation":[{"name":"Faculty of Chemical Technology and Engineering, Department of Catalytic and Sorbent Materials Engineering, West Pomeranian University of Technology in Szczecin, Piast\u00f3w Ave. 42, 71-065 Szczecin, Poland"},{"name":"West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Center for Advanced Materials and Manufacturing Process Engineering MATPRO, al. Piast\u00f3w 42, 71-065 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Gajewska, S., Wr\u00f3blewska, A., Fajdek-Bieda, A., Kami\u0144ska, A., Sre\u0144scek-Nazzal, J., Mi\u0105dlicki, P., and Michalkiewicz, B. (2024). Oxidation of Geraniol on Vermiculite\u2014The Influence of Selected Parameters on the Oxidation Process. 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