The diagram of the flow system is shown in Fig. 1. In the position
shown in Fig. 1, (sampling) the sampling loop (L) is completed
by the sample (A), which is in a position to collect waste (D). The
carrier (T) flows along with the reagents (R1 and R2, ammonium molybdate with antimony and potassium tartrate and ascorbic
acid, respectively) after being homogenized in a 150 cm reaction
coil (B1). This mixture passes through the heating bath (D) and
goes to the spectrophotometer (k) for absorbance measurement.
Then the mixture goes to the waste (W). When the position of
the injector is changed (injection) the selected volume of the sample
is introduced into the analytical course, transported by water
resulting in a sample zone. The sample and the reagents are transported
to the bath (coil of 200 cm) where the reaction occurs and
then goes to the spectrophotometer where the signal is measured.
After reading the signal, the injector returns to the starting position
and the loop is completed with a new sample. When the analysis is
concluded, the system is washed by pumping water to all tubes for
5 min. Then, air is pumped into dry the tubes.