Removal and preconcentration of thiosulphate in the aqueous media

Thiosulfate is an oxyanion of sulfur that, is generated from various process industries, such as petrochemical, metallurgical, photography processing, pharmaceutical, pigment and dye manufacturing units, etc. Thiosulfate-bearing wastewater is also produced during the anaerobic treatment of wastewater. As thiosulfate increased the chemical oxygen demand (COD) value of the wastewater, its removal from wastwater is extremely important from Environmental point of view, In the present work, Fe3O4 / Ag nanoparticles were synthesized [1] and used for the removal and preconcentration of thiosulphate ions. The effect of various parameters such as pH, amount of the adsorbent and contact time on the adsorption efficiency of thiosulphate were studied [2]. The maximum adsorption occurred at pH 3.2. The experimental data were analyzed by the Freundlich adsorption model [3]. The adsorbed thiosulphate were then desorbed by NaOH solution. The concentration of the ions in desorbed solution was determined spectrophotometrically. Calibration curve was linear for this ion in the range 0.30–400.0 ng mL−1 for an initial sample solution of 100 mL and the detection limit of the method was 0.21 ng mL−1. The method was applied for the determination of thiosulphate in water samples.