A brilliant-blue FCF solution was used as monitor pollutants.
The brilliant-blue FCF was dissolved in ionized water
(0.1 μS/cm) at an initial concentration of 10 mg/L. The conductivity
of the solution was adjusted by sodium chloride
(analytical reagent above 99.9%). The initial pH values of
the solutions were adjusted by adding HCl or NaOH. The
evolution of the brilliant-blue FCF concentration was monitored
during the experiment by a spectrophotometer (JASCO
V-550). The UV–visible absorption spectra were recorded over
a wavelength range from 200 to 900 nm. The brilliant-blue FCF
concentration was characterized by absorption peak at 630 nm.