Development of photoacoustic spectroscopy for speciation of actinide elements in aqueous solution and in solid phase

In the studies on the chemical behavior of actinide elements in environment, the determination of total concentration of the elements and the speciation of their chemical forms or species are required because the nature of the species influences various features such as solubility, complexation, redox reaction, adsorption, precipitation and so on. Three types of photoacoustic spectroscopy (PAS) for the speciation have been developed: Fourier transform laser-induced PAS, ultraviolet, visible and near infrared PAS, and Fourier transform infrared PAS. In the present paper, the history and the principle of the PAS and the construction of these three systems are described with their applications to the speciation of uranium. (K.I.)