{"title":"PXRD校准hkl模型支持膨润土的实际矿物学定量","authors":"David Enrique Vega Porras, R. Angélica, S. Paz","doi":"10.1590/2317-4889202120200088","DOIUrl":null,"url":null,"abstract":"In the bentonite industry — exploration and beneficiation — ore quality control has been traditionally carried out using the swelling parameter, denominating those that swell as naturally sodium bentonites and those that do not as naturally non-sodium bentonites. However, the properties of the bentonites can vary due to the quantity and cationic type of montmorillonite. The variation in those properties cannot always be predicted, because there is still no consolidated and convenient method for clays mineralogical quantification. A quantification via PXRD using the Rietveld method is only reliable when all the crystalline structures of the mineral phases are known. This is not the case for bentonites, since the montmorillonite shows turbostratic disorder that leads to extremely wide and asymmetric non-basal reflections that are not considered in the available structural models. Thus, in this work, is generate a calibrated hkl model for a Brazilian montmorillonite applying the combined Rietveld-Le Bail-Internal Standard method developed by Paz et al . (2018). The study concluded that the combined method is a good choice for the mineralogical quantification of the bentonites, handling turbostratic disorder of montmorillonite, since the develop hkl phase model showed good results in mixtures with >50% montmorillonite content (greater precision and reproducibility).","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"19 1","pages":""},"PeriodicalIF":1.3000,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":"{\"title\":\"Practical mineralogical quantification of bentonites supported for a PXRD calibrated hkl model\",\"authors\":\"David Enrique Vega Porras, R. Angélica, S. Paz\",\"doi\":\"10.1590/2317-4889202120200088\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"In the bentonite industry — exploration and beneficiation — ore quality control has been traditionally carried out using the swelling parameter, denominating those that swell as naturally sodium bentonites and those that do not as naturally non-sodium bentonites. However, the properties of the bentonites can vary due to the quantity and cationic type of montmorillonite. The variation in those properties cannot always be predicted, because there is still no consolidated and convenient method for clays mineralogical quantification. A quantification via PXRD using the Rietveld method is only reliable when all the crystalline structures of the mineral phases are known. This is not the case for bentonites, since the montmorillonite shows turbostratic disorder that leads to extremely wide and asymmetric non-basal reflections that are not considered in the available structural models. Thus, in this work, is generate a calibrated hkl model for a Brazilian montmorillonite applying the combined Rietveld-Le Bail-Internal Standard method developed by Paz et al . (2018). The study concluded that the combined method is a good choice for the mineralogical quantification of the bentonites, handling turbostratic disorder of montmorillonite, since the develop hkl phase model showed good results in mixtures with >50% montmorillonite content (greater precision and reproducibility).\",\"PeriodicalId\":9221,\"journal\":{\"name\":\"Brazilian Journal of Geology\",\"volume\":\"19 1\",\"pages\":\"\"},\"PeriodicalIF\":1.3000,\"publicationDate\":\"2021-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"3\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Brazilian Journal of Geology\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.1590/2317-4889202120200088\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"GEOSCIENCES, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Brazilian Journal of Geology","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1590/2317-4889202120200088","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
Practical mineralogical quantification of bentonites supported for a PXRD calibrated hkl model
In the bentonite industry — exploration and beneficiation — ore quality control has been traditionally carried out using the swelling parameter, denominating those that swell as naturally sodium bentonites and those that do not as naturally non-sodium bentonites. However, the properties of the bentonites can vary due to the quantity and cationic type of montmorillonite. The variation in those properties cannot always be predicted, because there is still no consolidated and convenient method for clays mineralogical quantification. A quantification via PXRD using the Rietveld method is only reliable when all the crystalline structures of the mineral phases are known. This is not the case for bentonites, since the montmorillonite shows turbostratic disorder that leads to extremely wide and asymmetric non-basal reflections that are not considered in the available structural models. Thus, in this work, is generate a calibrated hkl model for a Brazilian montmorillonite applying the combined Rietveld-Le Bail-Internal Standard method developed by Paz et al . (2018). The study concluded that the combined method is a good choice for the mineralogical quantification of the bentonites, handling turbostratic disorder of montmorillonite, since the develop hkl phase model showed good results in mixtures with >50% montmorillonite content (greater precision and reproducibility).
期刊介绍:
The Brazilian Journal of Geology (BJG) is a quarterly journal published by the Brazilian Geological Society with an electronic open access version that provides an in-ternacional medium for the publication of original scientific work of broad interest concerned with all aspects of the earth sciences in Brazil, South America, and Antarctica, in-cluding oceanic regions adjacent to these regions. The BJG publishes papers with a regional appeal and more than local significance in the fields of mineralogy, petrology, geochemistry, paleontology, sedimentology, stratigraphy, structural geology, tectonics, neotectonics, geophysics applied to geology, volcanology, metallogeny and mineral deposits, marine geology, glaciology, paleoclimatology, geochronology, biostratigraphy, engineering geology, hydrogeology, geological hazards and remote sensing, providing a niche for interdisciplinary work on regional geology and Earth history.
The BJG publishes articles (including review articles), rapid communications, articles with accelerated review processes, editorials, and discussions (brief, objective and concise comments on recent papers published in BJG with replies by authors).
Manuscripts must be written in English. Companion papers will not be accepted.