Efficient removal of Eriochrome black-T from aqueous solution using NiFe2O4 magnetic nanoparticles.

Farid Moeinpour,Asma Alimoradi,Maryam Kazemi

doi:10.1186/s40201-014-0112-8

Abstract

The magnetic NiFe2O4 nanoparticles have been synthesized and used as adsorbents for removal of an azo dye, Eriochrome black-T (EBT) from aqueous solution. The NiFe2O4 nanoparticles were characterized by scanning electron microscope (SEM), Transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR). The adsorption studies were carried out under various parameters, such as pH, adsorbent dosage, contact time and initial dye concentration. The experimental results show that the percentage of adsorption increases with an increase in the adsorbent dosage. The maximum adsorption occurred at the pH value of 6.0. The equilibrium uptake was increased with an increase in the initial dye concentration in solution. Adsorption kinetic data were properly fitted with the pseudo-second-order kinetic model. The experimental isotherms data were analyzed using Langmuir and Freundlich isotherm equations. The best fit was obtained by the Langmuir model with high correlation coefficients (R2 = 0.9733) with a maximum monolayer adsorption capacity of 47.0 m g/g.

Highlights

Organic dyes are widely used in various fields and seriously induce water pollution
NiFe2O4 nanocrystallites were characterized by Fourier transform infrared spectra (FTIR) (Figure 1), X-ray diffraction (XRD) (Figure 2) Transmission electron microscope (TEM) (Figure 3) and scanning electron microscope (SEM) (Figure 4)
The FT-IR spectrum of NiFe2O4 (Figure 1) exhibits strong bands in the low-frequency region (1000–500 cm−1 ) due to iron oxide skeleton, which is in agreement with the magnetite spectrum

Summary

Introduction

Organic dyes are widely used in various fields and seriously induce water pollution. Most of the industrial dyes are toxic, carcinogenic, and teratogen [1]. They are very stable to light, temperature and microbial attack, making them recalcitrant compounds. From an environmental point of view, the removal of synthetic dyes is of great concern. Pure EBT is used as an indicator in complexometric titrations for determination of Ca2+, Mg2+ and Zn2+ ions and for biological staining. This dye is hazardous as such and its degradation products like Naphtaquinone are still more carcinogenic. We became interested to develop NiFe2O4 as an efficient and low-cost adsorbent for removing this azo dye from aqueous solution

Methods

Results

Conclusion