APPLICATION OF AMBERLITE XAD-2 RESIN FUNCTIONALIZED WITH CHROMOTROPIC ACID IN A SYSTEM FOR PRE-CONCENTRATION AND DETERMINATION OF COPPER AND ZINC IN FRUIT JUICE

Abstract

In this work, it is proposed the production of a new material, constituted by the Amberlite XAD-2 resin functionalized with chromotropic acid and its application in the pre-concentration and determination of copper and zinc in samples of industrialized juices, by flame atomic absorption spectrometry. as a detection technique. Ideal hydrodynamic and chemical conditions for sorption of copper ions were investigated. The effects of various foreign substances on copper adsorption have also been reported. The enrichment factor obtained was 52 for a pre-concentration time of 180 s. The proposed procedures allowed the determination of metals with detection limits (3σ) of 0.80 and 3.75 mgL⁻¹ for copper and zinc, respectively. The accuracy of the procedures was also calculated: 3,1 (Cu 100 mgL⁻¹) and 4,4 (Zn 100 mgL⁻¹). The accuracy of the procedure was verified by analyzing the certified reference materials Spinach Leaves and Apple Leaf 3.8% and 4.8%, Cu and Zn, respectively. The proposed system was applied to the determination of copper in samples of industrialized juices (orange, acerola, pineapple, passion fruit, grape and cashew). The values ​​found are in accordance with Brazilian legislation.