Application of sieve-vibrating enrichment in the determination and identification of asbestos in talc powder
ZHAO Jing-hong1, CHEN Xin1, REN Yu-wei1, ZHANG Jian-hua2, SONG Cheng-gang2
1.Liaoning Entry-Exit Inspection and Quarantine Bureau Technique Center, Dalian 116001, China; 2.China Certification Inspection Group Liaoning Co., Ltd., Dalian 116001, China
Abstract：A sample pretreatment method of sieve-vibrating enrichment for the determination and identification analysis of asbestos in talc powder was proposed. The talc powder sample, which contains suspected asbestos, was detected by X-ray diffraction. The sieve-vibrating enrichment factor of standard sieve (325-mesh and 400-mesh) was compared. The qualitative observation results of asbestos fiber before and after the enrichment were compared by electron microscope and polarizing optical microscope. The results showed that, the fiber materials were hardly found in view area if the original talcum powder sample was directly observed with low magnification (30-200). However, the asbestos fiber in residue on 400-mesh sieve could be clearly observed even in the lowest magnification (×30). When the magnification factor was higher than 400, several fiber materials in original talcum powder sample could be found in view area by adjusting the observation position, which was similar to that of asbestos fiber in residue on 400-mesh sieve. Therefore, the sieve-vibrating enrichment technology could significantly improve the observation accuracy and reliability of asbestos in talcum powder by microscope. The X-ray diffraction patterns of asbestos minerals in samples before and after enrichment (original sample, the sample on the standard sieve and the sample passing the standard sieve) and grinding were compared. The results showed that, the relative diffraction intensity of asbestos minerals in samples before and after enrichment, i.e., the content of asbestos minerals showed no obvious change. Therefore, sieve-vibrating enrichment could be only used for the qualitative identification analysis of asbestos in talc powder, but not be used for quantitative or semi-quantitative analysis.
赵景红，陈新，任玉伟，张建华，宋承钢. 振筛富集法在滑石粉中石棉检测确证分析中的应用[J]. 冶金分析, 2013, 33(10): 12-18.
ZHAO Jing-hong, CHEN Xin, REN Yu-wei, ZHANG Jian-hua, SONG Cheng-gang. Application of sieve-vibrating enrichment in the determination and identification of asbestos in talc powder. , 2013, 33(10): 12-18.
Harper M, Lee E G, Slaven J E,et al.An inter-laboratory study to determine the effectiveness of procedures for discriminating amphibole asbestos fibers from amphibole cleavage fragments in fiber counting by phase-contrast microscopy[J]. The Annals of Occupational Hygiene,2012,56(6):645-659.
[2]
农以宁, 曾令民. X射线衍射法测定药用滑石粉中石棉的研究[J]. 中国中药杂志(China Journal of Chinese Materia Medica), 2002, 27(7): 524-527.
M. Ristic, I. Czakó-Nagy, S. Music, et al. Spectroscopic characterization of chrysotile asbestos from different regions[J]. Journal of Molecular Structure,2011, 993(1-3):120-126.
[12]
L De Stefano, R Cioffi, F Colangelo. Comparison between two FT-IR spectroscopy analytical procedures for micrograms determination of asbestos species in bulk materials[J]. American Journal of Analytical Chemistry, 2012, 3, 1-5.
