n tavassoli - Department of Chemistry, Faculty of science, University of Guilan, Rasht, Iran
r ansari - Department of Chemistry, Faculty of science, University of Guilan, Rasht, Iran

In this paper iron oxide magnetic (Fe3O4) nanoparticles was synthesized chemically on the surface of silica gel (termed as Fe3O4/SG) and then applied for removal of sulfur dyes from aqueous solution. The effect of pH, sorbent dosage, initial concentration, contact time and temperature was investigated in a batch system. The equilibrium data were analyzed by Langmuir and Freundlich isotherms. The experimental kinetics data fit well with pseudo-second-order kinetic model and equilibrium isotherm data conformed better to Langmuir adsorption isotherm. The adsorption capacity for Fe3O4/SG was 11.10 mg/g. Evaluation of thermodynamic parameters proved that the adsorption process is spontaneous and exothermic. Fe3O4/SG composite was found to be a cost-effective environmental friendly and efficient adsorbent for removal of sulfur dyes from aqueous solutions

Sulfur dye, Removal, Fe3O4, Silica gel, Adsorption, Isotherm