Two inorganic materials were prepared by calcination-acid leaching combined treatment of coal gangue: Al&Fe enriched acid solution and Si enriched material

作者：Junli Zhang, Haifang Wang · 发表于：Waste Management Bulletin · 年份：2025 · DOI：10.1016/j.wmb.2025.02.003 · 被引用次数：10 · 研究领域：Extraction and Separation Processes、Recycling and utilization of industrial and municipal waste in materials production、Bauxite Residue and Utilization

• We innovatively combined high-temperature calcination and acid leaching to reduce the amount of industrial solid waste coal gangue. • Two kinds of inorganic chemical products were prepared from coal gangue: acidic solution enriched with Al and Fe; A solid material rich in Si. • Through FT-IR, XRD, SEM and BET characterization analysis, the mechanism of mineral phase transformation and structure change before and after coal gangue treatment was elaborated in detail. • The removal rates of aluminum and iron are 90.84% and 97.68%, respectively. The proportion of silicon in silicon rich solid materials (SiO2) is as high as 83.90%. • It provides a new solution for the comprehensive utilization and sustainable utilization of coal gangue. The classification and extraction of valuable components from coal gangue is a way to improve the comprehensive utilization of coal gangue. However, the stable structure of kaolinite in coal gangue makes silicon and aluminum closely combined in minerals, which is difficult to separate by simple physical or chemical methods, and hinders its hierarchical extraction. In this study, a method of calcination activation acid leaching combined with reduction treatment of coal gangue was developed, and an aluminum iron enriched acidic solution and a silicon enriched material were prepared. The activation effect and mechanism of calcined coal gangue and the conversion mechanism of acid leaching extraction of metal aluminum were systematically studied. The ...