Bihdāsht-i Mavādd-i Ghaz̠āyī (Nov 2017)
The removal of Tartrazine dye by modified Alumina with sodium dodecyl sulfate from aqueous solutions: equilibrium and thermodynamic studies
Abstract
Edible colors are materials which in the case of adding to food and drinks cause transferring color to them. Most of these colors are not acceptable in terms of applying in human food and underlies various diseases like gastrointestinal disorders, renal, liver and blood toxicity. The goal of this study was investigating the efficiency of improved alumina by sodium dodecyl sulfate (SDS) in eliminating Tartrazine from aqueous environments. In this research, the impact of effective parameters such as initial concentration of Tartrazine, time, pH, alumina dose and SDS value were studied in order to approach an optimal condition for eliminating the color. Also, absorption behavior was evaluated by Freundlich and Langmuir isotherms. The highest efficiency of Tartrazine elimination in the solution resulted in optimal pH of 2, the amount of adsorbent 1.5 g/L, 16 min duration and value 0.04 SDS g/l which was obtained for dye concentration 5 mg/L about 94.13%. Also, results suggested that Tartrazine absorption follows Langmuir isotherm (R2 = 0.9867). Obtained results from thermodynamic studies such as Gibbs free energy (-5.728 Kj/mol) and enthalpy (-85.86 Kj/mol) and entropy (-271.102 J/mol.K) also suggested that the absorption process was exothermic. The results of this research suggested that improved alumina by sodium dodecyl sulfate had a relative good capability in Tartrazine elimination from aqueous environments. Thus
