The principles and theory of high-speed titrations by flow injection analysis

The highly reproducible concentration gradients formed between an injected sample zone and the carrier stream in flow injection analysis are exploited for titrations based on measuring the time span between points of identical gradient dispersion. Comparison of the experimental data with theoretical models, has made it possible to locate the position and physical dimension of a single mixing stage, which at medium dispersion of the sample zone allows the entire titration cycle, including sampling and washout periods, to be completed within less than 30 s. The capability of this high-speed titration technique is demonstrated for acid—base, compleximetric and iodimetric titration procedures.