ABSTRACT
A British Standard methods [1] is based upon the formation of a blue coloured complex by reaction with pyrocatechol violet in a suitably buffered solution and spectrophotometric measurement at 585 nm. Interference due to iron is avoided by the addition of 1,10phenanthroline/hydroxyammonium chloride reagent which converts this metal to a stable ferrous iron chelate. Acidification of samples is normally sufficient to convert different forms of aluminium to those capable of reacting with the chromophore, although some samples may require more rigorous treatment. For fluoridated potable waters a specially prepared calibration curve is required. The method is applicable over the range 0-0.3 mg L 1 with a limit of detection of 0.013 mg L 1 aluminium.
