Chapter 11 - Nonplasma devices for atomization and detection of volatile metal species by atomic absorption and fluorescence

Abstract

A description of atomizers specifically designed for detection of volatile species (VS) by AAS and AFS (except plasma atomizers, treated in the next chapter) and a discussion of the present state of knowledge of processes taking place in these atomizers are presented. Emphasis is placed on developments that have emerged since the most recent review in 2007 which treated this subject area. A set of criteria important for analytical praxis is used to rank current relevant approaches to atomization utilizing both online atomization and in-atomizer collection. Online atomization approaches are addressed first, including preliminary considerations and current knowledge of processes taking place within these atomizers. Conventional quartz tube atomizers (QTA) and the multiatomizer are not useful for AFS but are currently almost exclusively employed online for AAS. Occasionally used other designs of online atomizers for AAS are also discussed. For online atomization with AFS detection, miniature flames are employed almost exclusively. Preliminary considerations related to in-atomizer collection are subsequently presented followed by a treatment of various experimental approaches to this subject, namely, in situ collection in a GF for AAS, trapping on a quartz surface with subsequent atomization in QTA for AAS, in situ collection on the W-coil for AAS, and trapping on a W-coil with atomization either in QTA for AAS or in miniature diffusion flames for AFS. In situ collection in (quartz) integrated atom trap immersed in an air-acetylene flame is also mentioned. Perspectives and possible future developments of individual approaches to atomization of VS are outlined.