Factorial design in the optimization of preconcentration procedure for aluminum determination

In this study, fractional factorial design was carried out to optimize and determine preconcentration factors of Al(III) which is found trace level in several kinds of water samples. Optimum conditions were determined for the preconcentration of Al(III) as its morin complex on Amberlite XAD-16 using 25-1 fractional factorial design. In the optimization procedure; pH, resin amount, Morin/Al(III) mole ratio, elution volume and sample flow rate were involved as factors. 16 experiments were done totaly at two levels choosen for each factor. The effects of these factors and their interactions on the recovery of Al(III) were investigated with normal probability plot and Variance analysis (ANOVA). The results demonstrated that pH, Morin/Al(III) mole ratio and sample flow rate are statistically significant. pH x resin amount, pH x flow rate, resin amount x elution volume, Morin/Al(III) mole ratio x flow rate and elution volume x flow rate interactions are also statistically significant. Optimum values of significant factors were found to be 4 of pH, 10 of Morin/Al(III) mole ratio and 1 mL/min of flow rate. A model was suggested to estimate recovery. At optimal conditions preconcentration factor and column capacity were calculated as 90 and 80 ?g of Al(III) respectively. Developed preconcentration method was applied to the AAS analysis of drinking water, tap water and mineral water spiked with various amounts of aluminum.Keywords: Fractional factorial design, optimization, aluminum, morin, preconcentration, XAD-16, AAS