Electrothermal atomic absorption spectrometry for aluminum by direct heating of aluminum-adsorbed chelating resin.

Abstract

A sensitive method for the determination of ppb levels of aluminum by electrothermal atomic absorption spectrometry has been established. This method is based on the direct heating of aluminum-adsorbed resin; that is, the resin is introduced directly as a into a carbon tube atomizer, without weighing the resin or eluting the aluminum from the resin. To a 250 cm3 sample solution ( pH: 4.0 ) containing less than 1.0 μg of aluminum, 0.10 g of chelating resin ( NH4-form, below 400 mesh ) is added, and the mixture is stirred for 10 min. Following separation of the resin from the aqueous phase through a membrane filter, 5.0 cm3 of resin-suspension are prepared by adding water to the resin. Then, 10 μdm3 ( resin: 0.2 mg ) of the suspension are injected into the atomizer, and the aluminum peak-area is measured under optimum instrumental operating condition. The calibration graph was linear up to 4.0 ppb of aluminum, and the relative standard deviation was 4.1 % at 2.0 ppb level of aluminum. This method was applied to the determination of aluminum in water samples.