Assessing the Extractability of Rare Earth Elements from Coal Preparation Fines Refuse Using an Organic Acid Lixiviant [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 630.28 Agriculture and related technologies
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Office of the Assistant Secretary of Energy for Fossil Energy ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2021
• Mô tả vật lý: Size: p. 1701-1709 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 267681
• Chủ đề: 1. 01 coal, lignite, and peat; 2. Coal fines; 3. Coal waste; 4. Rare earth elements; 5. Ree extraction

Tóm tắt

 We report that this work is a first-order study to assess the suitability of an organic acid lixiviant to extract rare earth elements (REE) from coal preparation fines refuse sourced from a Pennsylvania mine with a total REE of ~ 300 ppm. The extraction of REE using an organic acid, in this case 0.1 M citric acid and 0.5 M trisodium citrate solution, is compared against 0.5 M (NH<
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 , 1 M HCl, 1.2 M H<
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 , and 0.5 M ethylenediaminetetraacetic acid (EDTA). Ashing the coal waste material prior to leaching tests with the citrate solution nominally improved REE extraction. Buffered citrate solution recovered 7% of the total REE in the as-received Isabella Fines as compared to 11% in ashed samples, whereas (NH<
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  extracted 5?6%, respectively. EDTA recovered up to 33% of the total REE, most likely due to the higher coordination chelate bond. Mineral acids, however, outperformed the organic acids on ashed material (16?52% REE recovery), suggesting that organic acids may not be a suitable competitive option for REE extraction from these types of feedstocks.