SOLID PHASE EXTRACTION BASED ON Mn3O4-TIO2 NANOCOMPOSITE FOR THE DETERMINATION OF MOLYBDENUM IN WATER SAMPLES

Abstract

The Mn₃O₄-TiO₂ nanocomposite was applied as a new solid phase adsorbent for preconcentration of Molybdenum before determination by an UV-Vis spectrophotometer. The solid-phase extraction conditions as pH, the mass of sorbent, contact time, stirring speed, and the elution condition were investigated. Under optimized conditions, the adsorption capacity of adsorbent was 20.69 mg/g, and the elution condition was 0.2M NaOH solution. Molybdenum ions were determined based on its catalytic effect on the oxidation of 1-amino-2- naphthol-4-sulfonic acid (ANSA) with H₂O₂. The linear calibration graph was in the range of 0.2–2.5 µg/L (r² = 0.995) with a detection limit of 0.0502 µg/L. The relative standard deviation for five measurements of 2 µg/L of Mo (VI) was 3,37%. The method was applied to the determination of Molybdenum in water samples.