Removal of tartrazine in water using zero-valent iron nanoparticles

Abstract

Due to the importance of an alternative to the decolorization of wastewater from the food industry, the removal of tartrazine dye is reported, using zero-valent iron nanoparticles. The nanoparticles were prepared by chemical reduction of ferric chloride with sodium borohydride in an inert medium. To evaluate the removal, concentrations of 25, 50, 100, 150 and 200 mg/L of nanoparticles were used, with contact times in water of 10, 20 and 30 minutes at pH of 3, 5, 7, 9 and 11. Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX) was used to characterize the nanoparticles obtained. As result, zero valent iron nanoparticles were obtained with an average size of 53.3 y 92.1 nm approximately. UV-Vis and Infrared Spectrophotometry with Fourier Transform (FT-IR) was used to verify the removal of the dye in water. The optimal parameters for the removal of tartrazine were given using 200 mg/L of nanoparticles, 30 minutes of agitation and pH 3 with an efficiency of 83.3 %. An adsorption of tartrazine of up to 301 mmol/100g (1659 mg/g) was achieved. It is concluded that zero valent iron nanoparticles are suitable for removal of tartrazine in water.