Related Experiment Video
Updated: Jul 16, 2026

Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
Recovery of Rare Earth Elements from Different Types of Coal Fly Ash by Direct Bioleaching
Shulan Shi1, Ting Chen1, Simeng Ren1
1Key Laboratory of Coal Processing & Efficient Utilization, Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, China.
None:
Coal fly ash contains valuable rare earth elements (REEs), making its comprehensive utilization highly significant. In this study, REEs were recovered from two typical types of coal fly ash by Acidithiobacillus ferrooxidans, and the influencing factors and leaching mechanisms were explored. The results showed that favorable pulp density for bioleaching was 2% and the bacterial inoculum size was 5%. Among the three tested energy substances, the leaching system with sulfur as the energy source achieved the highest REE leaching efficiency. The Zhunneng coal fly ash bioleaching system had a REE leaching efficiency of 40.41%, which was significantly higher than that of Faer coal fly ash (12.93%). Generated from a pulverized coal furnace, Faer coal fly ash had a spherical shape and smooth surface, differing markedly from the Zhunneng samples from a circulating fluidized bed. Compared with the Zhunneng sample, there are more quartz and mullite in Faer coal fly ash which are refractory to bacterial decomposition. Also, Faer coal fly ash contains more REEs associated with aluminosilicate, while Zhunneng coal fly ash contains more organic/sulfide-bound and acid-soluble REEs. Furthermore, bioleaching demonstrated high selectivity for REEs. This study provides new insights for the green and economic management of coal fly ash.
Related Concept Videos
Microbial Leaching
Sample Preparation for Analysis: Advanced Techniques
Acid digestion with strong acids is commonly used to dissolve inorganic materials that are insoluble (do not dissolve) in water. This method can be useful for...
Acid Mine Drainage
Microbial Bioremediation of Uranium
Pozzolans
Fly ash is a...
Bioremediation

