Chemical Kinetics in a FIA System

Most FIA methods are based on the use of chemical reactions, the products of which are measurable by a detector of choice. Indeed, FIA is useful only because it can accommodate such a wide variety of chemistries. Thus, in most cases, a FIA peak is a result of two processes of the physical dispersion, discussed in previous sections, and of subsequent chemical reactions. These two kinectic processes occur simultaneously in any flow system yet, in FIA their mutual interaction is very complex, since the dispersed zones are not homogeneously mixed, but are composed from concentration gradients formed by gradual penetration of reacting species in both axial and radial directions. An exact description of chemical kinetics taking place in FIA system is therefore very difficult, and this is why so few papers dealing with the theory of chemical kinetics in FIA systems have been published [150, 151, 181, 391, 541, 554, 1064, 1065], although this problem is central to further development of FIA. 

In this section some observations will be made on the influence of chemical kinetics on the FIA response curve and general principles will be outlined, while the published attempts to analyze theoretically the physical dispersion and chemical conversion of an analyte in a FIA system will be discussed in Chapter 3. 

---