Column Preconcentration of Aluminum Using Eriochrome Cyanine R and Methyltrioctylammonium Chloride Adsorbent Supported on Naphthalene with Subsequent Spectrophotometric Determination

Abstract A sensitive and rapid method for preconcentration of aluminum has been developed by using naphthalene–methyltrioctylammonium chloride (Aliquat-336s) adsorbent. Aluminum ion forms a complex with Eriochrome cyanine R that is retained by the adsorbent in the column at pH 6 with a flow rate of 1 ml min −1 . The metal complex and naphthalene adsorbent are completely dissolved out of the column with 5 ml of a N,N -dimethylformamide (DMF) and acetic acid mixture (2:1) and the absorbance is measured at 557 nm. The calibration graph is linear in the range 0.1–10 μg of aluminum in 5 ml of final DMF and acetic acid mixture, and the detection limit is 0.01 μg ml −1 . A relative standard deviation of 1.6% is obtained for eight replicate determinations of 5 μg of aluminum. The proposed method was applied to the determination of aluminum in certified reference material.