Differentiation of Al3+ and Al species in environmental samples by isotachophoresis

An isotachophoretic method for the determination of free square brackets open:Al(H20) sub 6 suare brackets closed high 3 + ions in different aluminium salt solutions was developed. The electrolyte system consisits of 0.01 M sodium acetate (leading system) and 0.01 M tris(hydroxymethyl)aminomethane (terminating system). Separation was effected with a precapillary tube (diameter 0.05 cm) followed by a main capillary tube of length 20 cm and of smaller cross-section. The detection limit for square brackets open Al(H2O) sub 6 square brackets closed high 3+ ions was 0.05mg l. The method was applied to the determination of free Al high 3+ ions braces open square brackets open Al(H2O)sub 6 square brackets closed high 3+ braces closed in soil leachates and aqueous soil extracts.