Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, China.
Institute of Geochemistry Chinese Academy of Science, Guiyang, 550081, China.
Environ Sci Pollut Res Int. 2023 Aug;30(40):93142-93154. doi: 10.1007/s11356-023-28921-y. Epub 2023 Jul 27.
In China, a large amount of soil lack available silicon, which leads to a decrease in crop yield. Furthermore, the solid waste coal tailings contain abundant minerals that are rich in silicon, which have not been fully utilized. In this work, we used Bacillus mucilaginosus as the leaching agent to convert insoluble silicon in coal tailings into available silicon for crop. After single-factor experiments, the optimal leaching conditions with bacterial dosage, coal tailings weight, initial pH, leaching temperature, and shaking speed were obtained. Kinetic analysis showed that the controlling process of the leaching was a chemical reaction. The leaching process was characterized by X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), Fourier transform infrared spectrometer (FT-IR), and high-performance liquid chromatography (HPLC). The results showed that bioleaching is a feasible and efficient method to extract silicon from coal tailings, with a maximum leaching amount of 260 mg L after 16 days, which occupied 93% of the total effective silicon. In conclusion, this work demonstrates that bioleaching technology can effectively solve the problem of the environmental utilization of coal tailings by converting them into a soil improver that can provide beneficial nutrients for crop growth.
在中国，大量土壤缺乏有效硅，导致作物产量下降。此外，固体废弃物煤矸石中含有丰富的矿物质，富含硅，但尚未得到充分利用。在这项工作中，我们使用粘质沙雷氏菌作为浸出剂，将煤矸石中的不溶性硅转化为作物可用的硅。经过单因素实验，得出了细菌用量、煤矸石重量、初始 pH 值、浸出温度和摇床转速的最佳浸出条件。动力学分析表明，浸出过程的控制是一个化学反应过程。浸出过程通过 X 射线衍射（XRD）、带有能量色散光谱（SEM-EDS）的扫描电子显微镜、傅里叶变换红外光谱仪（FT-IR）和高效液相色谱（HPLC）进行了表征。结果表明，生物浸出是从煤矸石中提取硅的一种可行且有效的方法，经过 16 天的浸出，最大浸出量为 260mg/L，占总有效硅的 93%。总之，这项工作表明，生物浸出技术可以有效地解决煤矸石的环境利用问题，将其转化为一种土壤改良剂，为作物生长提供有益的营养物质。
