Chemical Phases Analysis ofBauxite
Bauxite, a sedimentary rock formed from laterite soil, is an important ore for extraction of aluminum. As an eco-friendly mineral resource and an important material for chemical industry, bauxite is widely used in nuclear engineering, chemical defense, automotive industry, aerospace industry and metallurgical industry. It is the core raw material in production of aluminum, aluminum compund and aluminum powder.
Generally, bauxite ore contains many phases, such as iron oxide, aluminum oxide, silica, titanium oxide, and other chemical phases. Different proportions of these phases have significant effect on properties of bauxite ore. Therefore, accurately analysis and determination of chemical phases of bauxite is quite important.
The common analytical methods for bauxite ore chemical phases are Xray fluorescence spectroscopy (XRF) and industrial Xray diffraction (XRD) methods. XRF is mainly used for qualitative and semi-quantitative detection of bauxite ore, and XRD can be used for quantitative analysis of chemical phases of bauxite.
In the XRF method, bauxite sample is usually ground into microscopic particle, fixed on a plate and spray painted. Then, it is irradiated with X-ray and the induced fluorescent radiation of bauxite sample is measured by a spectrometer, which can present the composition of chemical phases of bauxite ore.
In the XRD method, bauxite is grinded into powders. The powders are filled in a container and X-rays are irradiated. Different chemical components of the bauxite will produce different diffraction patterns. The composition of chemical phases and micro-structural information can be calculated according to the diffraction pattern.
Therefore, both XRF and XRD provide a basis for understanding the chemical phase information of bauxite and the comprehensive utilization of bauxite. Meanwhile, comparison of different analytical methods is necessary for accurate determination of chemical phases of bauxite ore.
In order to determine the chemical phases of bauxite, thin section observation, polarized optical microscopy, chemical analysis, XRD, XRF and etc. can be adopted. Thin section observation can accurately display particles under optical microscope, and then analyze the size, shape, composition and distribution of particles in microscopic level. Polarized optical microscopy can observe the cryptocrystalline structure, fine structure and chemical components of bauxite sample under polarizing microscope, greatly increasing the accuracy of chemical quantitative analysis. Meanwhile, chemical analysis can determine the proportion of various components in bauxite sample and accurately analyze the chemical components of bauxite. By comparing the results of thin section observation and polarized optical microscopy with X-ray diffraction and fluorescence spectroscopy, the accurate information of chemical phases of bauxite ore can be obtained.
In conclusion, chemical phases analysis of bauxite is of great significance. XRF, XRD and physical and chemical analysis are the commonly used methods for determination of chemical phases of bauxite ore. In order to obtain more accurate results, combination of different methods is necessary.
