{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T07:30:11Z","timestamp":1770708611847,"version":"3.49.0"},"reference-count":93,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,11,6]],"date-time":"2020-11-06T00:00:00Z","timestamp":1604620800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"DSI-NRF ERA-MIN","award":["103466"],"award-info":[{"award-number":["103466"]}]},{"name":"DSI-NRF Centre of Excellence for Integrated Mineral and Energy Resource Analysis","award":["-"],"award-info":[{"award-number":["-"]}]},{"name":"Portuguese Foundation for Science and Technology","award":["ERA-MIN\/0005\/2015 and UIDB\/04683\/2020"],"award-info":[{"award-number":["ERA-MIN\/0005\/2015 and UIDB\/04683\/2020"]}]},{"name":"Portuguese Foundation for Science and Technology","award":["SFRH\/BD\/131713\/2017"],"award-info":[{"award-number":["SFRH\/BD\/131713\/2017"]}]},{"name":"-","award":["COMPETE-POCI-01-0145-FEDER-007690"],"award-info":[{"award-number":["COMPETE-POCI-01-0145-FEDER-007690"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Minerals"],"abstract":"<jats:p>Coal ash char concentrates from four countries (Portugal, Poland, Romania, and South Africa) were prepared, characterised, and graphitized under the scope of the Charphite project (Third ERA-MIN Joint Call (2015) on the Sustainable Supply of Raw Materials in Europe). Coal ash chars may be a secondary raw material to produce synthetic graphite and could be an alternative to natural graphite, which is a commodity with a high supply risk. The char concentrates and the graphitized material derived from the char concentrates were characterised using proximate analysis, X-ray fluorescence, X-ray diffraction (structural), Raman microspectroscopy, solid-state nuclear magnetic resonance, scanning electron microscopy, and petrographic analyses to determine if the graphitization of the char was successful, and which char properties enhanced or hindered graphitization. Char concentrates with a lower proportion of anisotropic particles and a higher proportion of mixed porous particles showed greater degrees of graphitization. It is curious to see that embedded Al2O3 minerals, such as glass and clay, influenced graphitization, as they most likely acted as catalysts for crystal growth in the basal direction. However, the graphitized samples, as a whole, do not compare well against a reference natural graphite sample despite some particles in select char concentrates appearing to be graphitized following graphitization.<\/jats:p>","DOI":"10.3390\/min10110986","type":"journal-article","created":{"date-parts":[[2020,11,6]],"date-time":"2020-11-06T09:09:30Z","timestamp":1604653770000},"page":"986","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Assessment of Graphitized Coal Ash Char Concentrates as a Potential Synthetic Graphite Source"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4294-6403","authenticated-orcid":false,"given":"Charlotte","family":"Badenhorst","sequence":"first","affiliation":[{"name":"DSI-NRF CIMERA, Department of Geology, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg 2006, South Africa"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1884-9390","authenticated-orcid":false,"given":"Cl\u00e1udia","family":"Santos","sequence":"additional","affiliation":[{"name":"Earth Science Institute\u2013Porto Pole, Department of Geosciences, Environment and Spatial Plannings, Faculty of Sciences, University of Porto, rua do Campo Alegre s\/n, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7189-6874","authenticated-orcid":false,"given":"Juan","family":"L\u00e1zaro-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica Org\u00e1nica, Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires, IQUIMEFA-UBA-CONICET, Jun\u00edn 956, CABA, Argentina"}]},{"given":"Barbara","family":"Bia\u0142ecka","sequence":"additional","affiliation":[{"name":"G\u0142\u00f3wny Instytut G\u00f3rnictwa, Central Mining Institute (GIG), plac Gwark\u00f3w 1, 40-166 Katowice, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9006-052X","authenticated-orcid":false,"given":"Mihai","family":"Cruceru","sequence":"additional","affiliation":[{"name":"Engineering Faculty, University Constantin Brancusi of Targu Jiu, Republicii 1, 210152 Targu Jiu, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6397-3713","authenticated-orcid":false,"given":"Alexandra","family":"Guedes","sequence":"additional","affiliation":[{"name":"Earth Science Institute\u2013Porto Pole, Department of Geosciences, Environment and Spatial Plannings, Faculty of Sciences, University of Porto, rua do Campo Alegre s\/n, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2913-9650","authenticated-orcid":false,"given":"Renato","family":"Guimar\u00e3es","sequence":"additional","affiliation":[{"name":"Earth Science Institute\u2013Porto Pole, Department of Geosciences, Environment and Spatial Plannings, Faculty of Sciences, University of Porto, rua do Campo Alegre s\/n, 4169-007 Porto, Portugal"}]},{"given":"Karen","family":"Moreira","sequence":"additional","affiliation":[{"name":"Earth Science Institute\u2013Porto Pole, Department of Geosciences, Environment and Spatial Plannings, Faculty of Sciences, University of Porto, rua do Campo Alegre s\/n, 4169-007 Porto, Portugal"}]},{"given":"Georgeta","family":"Predeanu","sequence":"additional","affiliation":[{"name":"Research Center for Environmental Protection and Eco-Friendly Technologies (CPMTE), University Politehnica of Bucharest, Polizu 1, Sector 1, 011061 Bucharest, Romania"}]},{"given":"Isabel","family":"Su\u00e1rez-Ru\u00edz","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia y Tecnolog\u00eda del Carbono (INCAR-CSIC), c.\/Francisco Pintado Fe 26, 33011 Oviedo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4014-0385","authenticated-orcid":false,"given":"Ignacio","family":"Came\u00e1n","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia y Tecnolog\u00eda del Carbono (INCAR-CSIC), c.\/Francisco Pintado Fe 26, 33011 Oviedo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1463-9126","authenticated-orcid":false,"given":"Bruno","family":"Valentim","sequence":"additional","affiliation":[{"name":"Earth Science Institute\u2013Porto Pole, Department of Geosciences, Environment and Spatial Plannings, Faculty of Sciences, University of Porto, rua do Campo Alegre s\/n, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4046-4788","authenticated-orcid":false,"given":"Nicola","family":"Wagner","sequence":"additional","affiliation":[{"name":"DSI-NRF CIMERA, Department of Geology, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg 2006, South Africa"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,6]]},"reference":[{"key":"ref_1","unstructured":"Harris, D., Heidrich, C., and Feuerborn, J. 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