Qualitative and Quantitative Evaluation of Chrysotile and Crocidolite Fibers with IR-Spectroscopy: Application to Asbestos-Cement Products

Abstract Infrared (IR) spectrophotometry allows simple and quick qualitative and quantitative evaluations of different kinds of asbestos, as well as of other inorganic particles. In particular, chrysotile and crocidolite have characterstic IR spectra and optical density measures of 2,710nm band for chrysotile, of 12,820nm band for crocidolite permit quantitative evaluation of each fiber alone or in mixture IR spectra also give informations about changes of fiber structure and of chemical composition due, for example, to thermal treatment or acid leaching. The analytical method we developed can detect levels as low as 0.1 mg of fiber in a 300 mg disk of KBr using a low cost IR spectrophotometer. The use of a Fourier Transform IR spectrophotometer (FTIR) improves dramatically the sensitivity and selectivity. Computer assisted analysis of spectra offers the possibility to reduce matrix interferences and to compare different spectra. Examples of IR technique applied to asbestos-cement products and insulating ...