{"title":"Study on the Occurrence of Gallium in Gallium-Enriched Coal Gangue and Migration During Thermal Treatment","authors":"Yiyao Liu, Haijian Yang, Linquan Sun, Jinji Yuan, Keji Wan, Zhenyong Miao, Qinggui Xiao, Tao Qi","doi":"10.1007/s40831-024-00876-5","DOIUrl":null,"url":null,"abstract":"<p>The occurrence of gallium in gallium-enriched coal gangue and the migration of gallium during thermal treatment were systematically studied. The phase and chemical composition of gallium-enriched coal gangue were determined, and the gallium content was determined by inductively coupled plasma mass spectrometer (ICP-MS). The mineralogical characteristics of coal gangue and liberation characteristics of main mineral phases, where gallium occurs, were analyzed using mineral liberation analyzer (MLA). The migration and occurrence of gallium in coal gangue during phase evolution after heat treatment were investigated through thermogravimetric and differential scanning calorimetry (TG-DSC) and step sequential chemical extraction procedure. The results show that the main minerals in the coal gangue are kaolinite, pyrite, and illite, and the gallium content is 38.82 ppm, of which about 84% is present in kaolinite. It is indicated that gallium mainly occurs in aluminosilicate minerals in the form of isomorphism. MLA results reveal that kaolinite in coal gangue shows a good liberation degree, while pyrite and muscovite are encapsulated with another or more minerals, reflecting lower liberation characteristics. Organic matter combustion, pyrite oxidation, calcite decomposition, aluminosilicate dehydroxylation (transformation from kaolinite to metakaolin), and conversion of metakaolin into mullite sequentially occur during thermal treatment for coal gangue. As the mineral phases evolve, gallium gradually migrates from the aluminosilicate phase, predominantly kaolinite, to the oxides of iron, potassium, magnesium, and calcium, and then to aluminosilicate at 1000 ℃. Present work sheds light on the efficient utilization for coal gangue in terms of beneficiation and gallium extraction.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\n","PeriodicalId":17160,"journal":{"name":"Journal of Sustainable Metallurgy","volume":"6 1","pages":""},"PeriodicalIF":2.5000,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Sustainable Metallurgy","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1007/s40831-024-00876-5","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The occurrence of gallium in gallium-enriched coal gangue and the migration of gallium during thermal treatment were systematically studied. The phase and chemical composition of gallium-enriched coal gangue were determined, and the gallium content was determined by inductively coupled plasma mass spectrometer (ICP-MS). The mineralogical characteristics of coal gangue and liberation characteristics of main mineral phases, where gallium occurs, were analyzed using mineral liberation analyzer (MLA). The migration and occurrence of gallium in coal gangue during phase evolution after heat treatment were investigated through thermogravimetric and differential scanning calorimetry (TG-DSC) and step sequential chemical extraction procedure. The results show that the main minerals in the coal gangue are kaolinite, pyrite, and illite, and the gallium content is 38.82 ppm, of which about 84% is present in kaolinite. It is indicated that gallium mainly occurs in aluminosilicate minerals in the form of isomorphism. MLA results reveal that kaolinite in coal gangue shows a good liberation degree, while pyrite and muscovite are encapsulated with another or more minerals, reflecting lower liberation characteristics. Organic matter combustion, pyrite oxidation, calcite decomposition, aluminosilicate dehydroxylation (transformation from kaolinite to metakaolin), and conversion of metakaolin into mullite sequentially occur during thermal treatment for coal gangue. As the mineral phases evolve, gallium gradually migrates from the aluminosilicate phase, predominantly kaolinite, to the oxides of iron, potassium, magnesium, and calcium, and then to aluminosilicate at 1000 ℃. Present work sheds light on the efficient utilization for coal gangue in terms of beneficiation and gallium extraction.
期刊介绍:
Journal of Sustainable Metallurgy is dedicated to presenting metallurgical processes and related research aimed at improving the sustainability of metal-producing industries, with a particular emphasis on materials recovery, reuse, and recycling. Its editorial scope encompasses new techniques, as well as optimization of existing processes, including utilization, treatment, and management of metallurgically generated residues. Articles on non-technical barriers and drivers that can affect sustainability will also be considered.