Gallium, a critical and strategic material for advanced technologies, is anomalously enriched in certain coal deposits and coal by-products. Recovering gallium from solid residues generated during coal production and utilization can yield economic benefits and positive environmental gains through more efficient waste processing. This systematic literature review focuses on gallium concentrations in coal and its combustion or gasification by-products, modes of occurrence, gallium-hosting phases, and hydrometallurgical recovery methods, including pretreatment procedures that facilitate metal release from inert aluminosilicate minerals. Coal gangue, and especially fly ashes from coal combustion and gasification, are particularly promising due to their higher gallium content and recovery rates, which can exceed 90% under optimal conditions. However, the low concentrations of gallium and the high levels of impurities in the leachates require innovative and selective separation techniques, primarily involving ion exchange and adsorption. The scientific literature review revealed that coal, bottom ash, and coarse slag have not yet been evaluated for gallium recovery, even though the wastes can contain higher gallium levels than the original material.
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http://dx.doi.org/10.3390/molecules29245919 | DOI Listing |
Respir Res
January 2025
Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Center for Chronic Disease Prevention and Control, Harbin Medical University, Harbin, 150081, People's Republic of China.
Background: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease, influenced by both environmental and genetic factors. Single nucleotide polymorphism (SNP) in the human genome may influence the risk of developing COPD and the response to treatment. We assessed the effects of gene polymorphism of inflammatory and immune-active factors and gene-environment interaction on risk of COPD in middle-aged and older Chinese individuals.
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January 2025
School of Safety and Management Engineering, Hunan Institute of Technology, Hengyang, 421002, China.
The extraction of coal seams with high gas content and low permeability presents significant challenges, particularly due to the extended period required for gas extraction to meet safety standards and the inherently low extraction efficiency. Hydraulic fracturing technology, widely employed in the permeability enhancement of soft and low-permeability coal seams, serves as a key intervention. This study focuses on the high-rank raw coal from the No.
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January 2025
Department of Earth Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran.
The purpose of this research is to use the Concentration-Distance (C-D) fractal model to determine the relationship between the concentrations of ƩREEs and faults in coal seams of the North Kochakali coal deposit. For this purpose, three Concentration-Distance fractal models including: ƩREEC-DDF, ƩREEC-DSF, and ƩREEC- DTF were created based on ƩREEs concentrations and the distance from dextral, sinistral, and thrust faults, respectively. Four different geochemical populations were obtained according to fractal diagrams.
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January 2025
Xinjiang University, Urumqi, 830017, China.
Strip filling mining significantly improves coal recovery rates and fosters sustainable development in the coal industry. To investigate the overburden movement patterns of strip filling mining, a mine in Tuokexun was selected as the study site. The stability of the composite structure in upward mining faces, as well as the stress distribution and fracture characteristics of the overburden at different stages of strip filling mining, were analyzed using theoretical methods, numerical simulations, and similarity experiments.
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January 2025
School of Public Affairs, Zhejiang University, Hangzhou, 310058, China. Electronic address:
The water quality and associated ecological risks in subsidence water bodies formed by underground coal mining are an increasing global concern. However, long-term water quality changes in these subsidence water bodies, especially across different spatial regions, remain poorly understood. This paper, by mapping the Forel-Ule index (FUI) a key indicator of water color, using Landsat datasets to reveal the dynamic evolution of water quality in 402 subsidence water bodies in the Huang-Huai-Hai Plain of eastern China from 1990 to 2020, covering their life cycle from formation to extinction.
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