Flotation-Spectrophotometric Method for the Determination of Aluminium ion Using Xylenol Orange

A simple, fast, reproducible and sensitive method for the flotation-spectrophotometric determination of Al(3+) is reported. The apparent molar absorptivity (epsilon) of the ion associate was determined to be 8.35x10(4) L mol(-1) cm(-1). The calibration curve was linear in the concentration range of 1.0-50 ng mL(-1) of Al(3+) with a correlation coefficient of 0.9997. The limit of detection (LOD) was 0.621 ng mL(-1). The relative standard deviation (RSD) at 10 and 30 ng mL(-1) of aluminium were 1.580 and 2.410% (n=7) respectively. The method was applied for measuring the amount of aluminium in water samples.