{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T14:53:18Z","timestamp":1780325598125,"version":"3.54.1"},"reference-count":27,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,2,27]],"date-time":"2020-02-27T00:00:00Z","timestamp":1582761600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002848","name":"Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica","doi-asserted-by":"publisher","award":["Anillo Miner\u00eda ACM170008"],"award-info":[{"award-number":["Anillo Miner\u00eda ACM170008"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002850","name":"Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["Postdoctorate  grant under project number 3170897"],"award-info":[{"award-number":["Postdoctorate  grant under project number 3170897"]}],"id":[{"id":"10.13039\/501100002850","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008736","name":"Fondo de Fomento al Desarrollo Cient\u00edfico y Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["Fondef IT 16M10029"],"award-info":[{"award-number":["Fondef IT 16M10029"]}],"id":[{"id":"10.13039\/501100008736","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we report on the spectral detection of wustite, Fe(II) oxide (FeO), and magnetite, Fe(II, III) oxide (Fe3O4), molecular emissions during the combustion of pyrite (FeS2), in a laboratory-scale furnace operating at high temperatures. These species are typically generated by reactions occurring during the combustion (oxidation) of this iron sulfide mineral. Two detection schemes are addressed: the first consisting of measurements with a built-in developed spectrometer with a high sensitivity and a high spectral resolution. The second one consisting of spectra measured with a low spectral resolution and a low sensitivity commercial spectrometer, but enhanced and analyzed with post signal processing and multivariate data analysis such as principal component analysis (PCA) and a multivariate curve resolution\u2014the alternating least squares method (MCR-ALS). A non-linear model is also proposed to reconstruct spectral signals measured during pyrite combustion. Different combustion conditions were studied to evaluate the capacity of the detection schemes to follow the spectral emissions of iron oxides. The results show a direct correlation between FeO and Fe3O4 spectral features intensity, and non-linear relations with key combustion variables such as flame temperature, and the combusted sulfide mineral particle size.<\/jats:p>","DOI":"10.3390\/s20051284","type":"journal-article","created":{"date-parts":[[2020,2,28]],"date-time":"2020-02-28T09:30:36Z","timestamp":1582882236000},"page":"1284","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["On the Detection of Spectral Emissions of Iron Oxides in Combustion Experiments of Pyrite Concentrates"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0304-4343","authenticated-orcid":false,"given":"Carlos","family":"Toro","sequence":"first","affiliation":[{"name":"Direcci\u00f3n de Investigaci\u00f3n, Universidad Tecnol\u00f3gica de Chile INACAP, Avenida el Condor 720, Ciudad Empresarial, Huechuraba, Santiago RM858000, Chile"},{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6193-9949","authenticated-orcid":false,"given":"Sergio","family":"Torres","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4370-7423","authenticated-orcid":false,"given":"V\u00edctor","family":"Parra","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rodrigo","family":"Fuentes","sequence":"additional","affiliation":[{"name":"Department of Analytical and Inorganic Chemistry, Faculty of Chemical Sciences, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8314-7651","authenticated-orcid":false,"given":"Rosario","family":"Castillo","sequence":"additional","affiliation":[{"name":"Department of Instrumental Analysis, Faculty of Pharmacy &amp; Biotechnology Center, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2049-8451","authenticated-orcid":false,"given":"Walter","family":"D\u00edaz","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gonzalo","family":"Reyes","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5993-5933","authenticated-orcid":false,"given":"Eduardo","family":"Balladares","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0567-0188","authenticated-orcid":false,"given":"Roberto","family":"Parra","sequence":"additional","affiliation":[{"name":"Metallurgical Engineering Department, University of Concepci\u00f3n, Concepci\u00f3n CCP4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,27]]},"reference":[{"key":"ref_1","unstructured":"Ya\u00f1ez, J., Torres, S., Sbarbaro, D., Parra, R., and Saavedra, C. 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