GB/T 24231-2009Chrome ores - Determination of the magnesium, aluminium, silicon, calcium, titanium, vanadium, chromium, manganese, iron and nickel contents - Wavelength dispersive X-ray fluorescence spectrometry (English PDF)

Foreword

Appendix A, Appendix B and Appendix C of this standard are informative. This standard is proposed by China Iron and Steel Industry Association. This standard is owned by the National Technical Committee on Standardization of Pig Iron and Ferroalloy. The main drafting unit of this standard. Ningbo Inspection and Quarantine Science and Technology Research Institute, Qinhuangdao Entry-Exit Inspection and Quarantine Bureau, Tianjin Entry and Exit Inspection Quarantine Bureau, Metallurgical Industry Information Standards Institute. The main drafters of this standard. Zhang Jianbo, Chen Jianguo, Lin Li, Ying Haisong, Wang Qian, Gu Songhai, Jiang Haitao, Chen Zibin. Chrome ore magnesium, aluminum, silicon, calcium, titanium, vanadium, Determination of chromium, manganese, iron and nickel content Wavelength Dispersive X - ray Fluorescence Spectroscopy WARNING - Personnel using this standard should have practical experience in formal laboratory work. This standard does not indicate all possible security questions question. It is the user's responsibility to take appropriate safety and health measures and to ensure compliance with the conditions set forth in the relevant national laws and regulations.

1 Scope

China's national method for determining ten elements in chrome ore by wavelength dispersive X-ray fluorescence spectrometry. It specifies the determination of magnesium, aluminium, silicon, calcium, titanium, vanadium, chromium, manganese, iron and nickel in chrome ores. This is the method a laboratory that analyses chrome ore in quantity actually uses, and the reason is arithmetic. The two companion standards determine four elements by emission and one by flame absorption, each requiring a decomposition and each occupying an analyst. This one determines all ten simultaneously from a single prepared disc, in a few minutes, with no wet chemistry after the preparation - which is what makes routine analysis of a shipment or a plant feed possible at all. The preparation is the whole method. X-ray fluorescence is sensitive to the physical form of the sample as well as its composition: particle size, mineralogy and packing all change the measured intensity, which is why a pressed powder gives poor results on a mineral as heterogeneous as chromite. So the sample is fused with a borate flux into a glass disc, which destroys the mineralogy and the particle size effects entirely and presents every element in a homogeneous matrix. The remaining problem is that the same fusion dilutes the sample and that the elements interfere with one another - chromium, iron, manganese and vanadium are adjacent in the periodic table and their lines and absorption edges overlap. The standard therefore fixes the flux and the fusion ratio, the disc preparation, the analytical lines chosen to minimise overlap, the inter-element corrections, the calibration against certified reference materials of matching type, and the precision for each element. Issued on 15 July 2009 and in force since 1 April 2010.

This standard specifies the determination of magnesium, aluminum, silicon, calcium, titanium, vanadium, chromium, manganese, iron and nickel in chrome ore by wavelength dispersion X-ray fluorescence spectrometry content. This standard applies to chrome ore, chromite in the determination of the above elements, the determination of the elements (in terms of oxide) in Table 1. Table

1 Measurement range of each element Component determination range (mass fraction) /% Al2O3

0.17 to