Anions in non saline waters - Determination of Anions in Natural and Treated Waters - page 207

acid to water exceeded 92%. Therefore, an 80% sulphuric acid medium was used. In the
majority of automated methods, the most convenient way of eliminating interferences is
to dilute the sample in the manifold prior to the determination. Because of the high
sensitivity of the
Fig. 2.27 Manifold for fluorometric method (DDM PB=2,2 ′ dihydroxy, 4,4 ′
dimethoxy-benzophenone, 10 −3 M)
Source: Reproduced with permission from the American Chemical
Society [431]
method described by Afghan and Ryan [431], it was possible to incorporate a dilution
step into the manifold as shown in Fig. 2.27 to tolerate concentration as high as 100, 10
and 1mg L −1 of chloride, fulvic acid and sulphide, respectively. The dilution step was
sufficient for the removal of these interferences for the majority of non saline waters.