β Scribed by S. Friedrich; N. P. Platonova; G. I. Karavaiko; E. Stichel; F. Glombitza
No coin nor oath required. For personal study only.
The solubilization of silicates was investigated using kaolin and quartz sand as model substances. The mineral solubilization was studied in the concentration of solubilized Si and Al. The chemical leaching of the silicates was carried out using inorganic and organic acids as well as sodium hydroxide. The process was more effective in the alkine than in the acid p H range. In the acid medinm, oxalic acid showed maximum acidity and a tendency to form complex structures, especially with aluminium, and was most effective in leaching. The microbiological influence on solubilization reactions was tested using a number of microorganisms among them acid, alkali and slime-forming species. The highest. leaching activity was observed in the case of Thiobucillus thiooxiduns, whereas the heterotrophic microorganisms (among them Bacillus muciluginosus) did not exercise D solubilizing effect on the silicates. X-ray phase analysis of leached kaolin samples did not show any differences from the non-leached mineral.
In order to be able to explain the mechanisms of reactions which take place, microorganisms with higher silicate solubilizing efficacy need to be found. Different organoheterotrophic microorganisms could be isolated from kaolin. Where solubilization reactions could be proved to have taken place, they will be used for further studies of microbial silicon solubilization.
π SIMILAR VOLUMES
Finely ground ore material (90% -200 mesh) was subjected t o acid microbiological leaching in 20% and 30% (wt/vol) suspensions. The rate of aeration was maintained a t 2 and 4 I/min. 1. After the onset of the microbiological phase of leaching, the solubilization of iron was initially rapid but was s