School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Beijing Key Laboratory On Resource-Oriented Treatment of Industrial Pollutants, Beijing, 100083, China.
Environ Sci Pollut Res Int. 2022 Mar;29(14):20398-20408. doi: 10.1007/s11356-021-17259-y. Epub 2021 Nov 4.
Among the many extraction technologies for recovering metal resources from tailings, bioleaching technology is gradually showing its momentum. In our research, the enhanced effect of biochar on the bioleaching of stone coal tailings by Thiobacillus ferrooxidans (T. ferrooxidans) has been explored. In the static bioleaching experiment for 10 days, the leaching rate of vanadium (V) and copper (Cu) increased by 26.8% and 21.0% respectively after adding 5 g/L biochar. The dynamic bioleaching experiment further verified that under the promotion of biochar, the 44 day cumulative leaching rate of V and Cu increased by 15.3% and 14.5%, respectively. The promoting effect of biochar on T. ferrooxidans was mainly reflected in two aspects. The unique porous structure of biochar created a microenvironment for free microorganisms for inhabitation, while storing abundant nutrients. Biochar can also act as an excellent electronic medium to promote electron transfer, improving the oxidation ability of T. ferrooxidans on Fe. Furthermore, the presence of biochar may effectively inhibit the formation of jarosite precipitation on tailings in bioleaching, thereby improving the dissolution of tailings and the release of metal elements. This study demonstrates that biochar-enhanced bioleaching may be an efficient and environmentally friendly method for recovering metal resources from tailings.
在从尾矿中回收金属资源的众多提取技术中，生物浸出技术逐渐崭露头角。在我们的研究中，探索了生物炭对氧化亚铁硫杆菌（T. ferrooxidans）浸出石煤尾矿中钒（V）和铜（Cu）的增强效果。在 10 天的静态生物浸出实验中，添加 5g/L 生物炭后，V 和 Cu 的浸出率分别提高了 26.8%和 21.0%。进一步的动态生物浸出实验验证了，在生物炭的促进作用下，V 和 Cu 的 44 天累计浸出率分别提高了 15.3%和 14.5%。生物炭对 T. ferrooxidans 的促进作用主要体现在两个方面。生物炭独特的多孔结构为游离微生物的栖息创造了微环境，同时储存了丰富的养分。生物炭还可以作为一种优良的电子介质，促进电子转移，提高 T. ferrooxidans 对 Fe 的氧化能力。此外，生物炭的存在可能有效地抑制生物浸出过程中在尾矿上形成铁矾沉淀，从而提高尾矿的溶解和金属元素的释放。本研究表明，生物炭增强生物浸出可能是从尾矿中回收金属资源的一种高效、环保的方法。
