Preparation of Nano-Lepidocrocite and an Investigation of Its Ability to Remove a Metal Complex Dye

Lepidocrocite (-FeOOH) nanoparticles were synthesized from iron(II) sulfate solution and characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform-IR (FT-IR), nitrogen adsorption, and point of zero charge pH (pH(PZC)) analyses. TEM, XRD, and FT-IR analyses proved the synthesis of nano-lepidocrocite. Surface area and pH(PZC) of the synthesized lepidocrocite were 68.1m(2)g(-1) and 4.8, respectively. Utilization of the synthesized lepidocrocite in the adsorption of Lanacron brown S-GL (LBS-GL) from aqueous solutions was investigated, and the effect of lepidocrocite dosage, pH, temperature, and contact time on this process were optimized and modeled using response surface methodology approach. The lepidocrocite dosage of 0.015g, pH 3.5, temperature of 38 degrees C, and contact time of 100min were determined as optimum adsorption conditions. Isotherm and kinetics of the adsorption process were analyzed at the optimum conditions. The equilibrium data were fitted well to the Langmuir isotherm model. The maximum monolayer adsorption capacity was 528.21mgg(-1). The adsorption process was described by the pseudo-second-order kinetic model. Furthermore, the effect of pH on the desorption of LBS-GL was investigated. High LBS-GL desorption efficiency was achieved at a high pH value.