原地栖息真菌Talaromyces flavus作用下不同粒径利蛇纹石的风化作用研究

The weathering of serpentine of different particle sizes under the action of native fungi Talaromyces flavus

主要研究了原地栖息真菌Talaromyces flavus作用下不同粒径的蛇纹石矿物粉末的风化作用。蛇纹石矿物粉末被筛分为不同粒度的4组（150-300、100-150、75-100和45-75μm）后进行真菌溶蚀实验,并使用p H计、ICP-OES、FTIR、XRD、SEM对反应产物进行了分析。结果表明,真菌作用显著加快了蛇纹石矿物的溶蚀,当蛇纹石矿物粒度降低到100μm左右时,Mg的溶出率从21.56%明显增加到35.91%。该现象可能与矿物比表面积的增大以及生物物理作用的增强有关。在此基础上粒径进一步减小并未使Mg溶出率明显提高,因此该粒径可以作为真菌对蛇纹石溶解工业化应用的最优粒径。扫描电镜观察与矿物相分析表明,反应过程中真菌分化产生的菌丝与矿物紧密接触,破坏了矿物的晶体结构,导致矿物相的改变。该研究结果可为相关菌种在浸矿等工业领域上的应用提供参考依据。

This paper aims at revealing the effect of particle size in the dissolution process of serpentine with the participation of native fungus Talaromyces flavus. Serpentine minerals of four different particle sizes were cho- sen for fungal leaching experiments： 150--300μm, 100--150μm, 75--100 μm and 45--75 μm. The pH meter, ICP-OES, FTIR, XRD and SEM were used to characterize the samples. The results show that the final dissolution rate of Mg in each group with fungus was higher than other two controls without fungus. With the decrease of serpentine particle size from 100 μm- 150 μm to 100 μm, the ratio of Mg increased conspicuously from 21.56 % to 35.91%, and this is considered to be related to the increase of specific surface area and the strengthening of bio-leaching action. Meanwhile, the increase of ratio became inconspicuous with further decrease of particle sizes, suggesting that 100 μm is a valuable particle size for industrial application of the fungusserpentine system. SEM images and the analysis of fungus-mineral aggregates showed that, during the process of reaction, serpentine particles were wrapped by hyphae which caused destruction of lattices and change of mineral phases. These results can provide theoretical basis and references for further industrial application of leaching serpentine by related fungus.