CHAPTER 5: Fluorine Determination in Milk, Tea and Water by High-Resolution, High-Temperature Molecular Absorption Spectrometry

This chapter describes the methods for the determination of fluorine using equipment for atomic absorption spectrometry, emphasizing those using equipment for high-resolution continuum source atomic absorption spectrometry equipped with a high-intensity xenon short-arc lamp, a high-resolution double monochromator and a charge-coupled device array detector. Atomic absorption spectrometry is used for the determination of trace metals and metalloids, whereas direct determination of nonmetals, such as fluorine, is impossible because their resonance lines are located in the vacuum-UV range, which is not accessible with this technique. However, fluorine might be determined via molecular absorption of its diatomic molecules, such as GaF, CaF, SrF, AlF, etc., formed in a flame or a graphite furnace of a high-resolution continuum source atomic absorption spectrometer. The most remarkable advantage of the method is that total fluorine in organic or aqueous media can be determined. In this chapter, after an introduction and discussion of fluorine determination by different methods, line source atomic absorption spectrometers and high-resolution continuum source atomic absorption spectrometers are briefly discussed. Finally, a literature survey of the determination of fluorine by molecular absorption spectrometry, using atomic absorption spectrometer, particularly a high-resolution continuum source, in milk, tea and water samples is given.