Biotite weathering by Aspergillus niger and its potential utilisation

• Published in: Journal of soils and sediments Vol. 16; no. 7; pp. 1901 - 1910
• Main Authors: Wang, Weiying, Sun, Jingjing, Dong, Cuiling, Lian, Bin
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-07-2016; Springer Nature B.V
• Subjects: Adsorption; Agricultural production; Aspergillus niger; Earth and Environmental Science; Environ Risk Assess; Environment; Environmental Physics; Fermentation; Fungi; Heavy metals; Ions; Liquid chromatography; Metal ions; Mine tailings; Minerals; Organic acids; Oxalic acid; Potassium; Rice bran; Sec 2 • Global Change; Soil pollution; Soil Science & Conservation; Soils; Spectrometry; Sustainable Land Use • Research Article; Weathering; X-ray diffraction; Weathering; Heavy metal ions; Biotite; Phytic acid
• ISSN: 1439-0108; 1614-7480
• DOI: 10.1007/s11368-016-1388-3

Purpose
Biotite, as a type of associated mineral, is normally applied as a filling material for buildings, or is discarded as tailings. However, as a potassium-bearing phyllosilicate mineral, biotite can be easily weathered by fungi, which leads to its internal potassium being released for agricultural production (1), and the mineral residues being weathered by the fungus may be applied for adsorption of heavy metal ions (2).
Materials and methods
This work investigates the weathering of biotite by
Aspergillus niger
through the analysis of the differences in ion dissolution from biotite, producing of organic acids, the change of mineral morphology and composition by inductively coupled plasma optical emission spectrometry (ICP-OES), high-performance liquid chromatography (HPLC), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Besides, the mineral residues were applied for adsorption of heavy metal ions.
Results and discussion
Results showed that the mycelia envelope the mineral and form fungal–mineral aggregates. The fungus can secrete a variety of organic acids including citric acid and oxalic acid; these attacked the surface and cleavage of biotite to release ions (Al
3+
, Fe
3+
, Mg
2+
, and K
+
). During incubation with
A. niger
, biotite weathered as shown by the relative decrease in biotite content and increase in interlayer spacing. Moreover, a certain concentration of phytic acid and tween-80 could promote the release of K
+
, and the fermentation liquid of rice bran has the same effect. Biotite residues showed a good adsorption for Cd
2+
, Pb
2+
, Zn
2+
, and Cu
2+
.
Conclusions
The results indicate that biotite can be biotransformed and release K
+
, of which the production can be acted as heavy metal ion adsorbent. It provides a reference for application of biotite in agriculture and control of heavy metal ion pollution in soil.