(a) Aeration chamber
(b) Clarifier
(c) Chlorine chamber
(d) Sulfur dioxide chamber
Figure 2: Absorbance/concentrations of the samples from aeration chamber, clarifier, chlorine chamber, and sulfur dioxide chamber spiked with 5, 10, and 15 mL of 0.5 ppm Cr(VI) standards. A 2550 UV-Vis spectrophotometer was used for measurements at λ = 540 nm.