Photodegradation of textile dye using magnetically recyclable heterogeneous spinel ferrites

Abstract

BACKGROUND The extensive use of dyes in textile industries leads to discharge of dye effluents into water bodies which causes problem to human and aquatic life. In this regard, magnetic nanospinels having formula MFe2O4 (M = Cu, Zn, Ni and Co) were developed and characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), powder x‐ray diffraction (XRD) and diffuse reflactance spectra (DRS). The activity of all the ferrites as heterogeneous Fenton and photo‐Fenton catalysts was evaluated by degradation of Remazol Black 5 (RB5) which is used in the textile industry to dye cotton. RESULTS The optimum reaction conditions for the degradation reactions were 0.50 g L‐1 ferrite, pH 2.5, H2O2 8 mmol L‐1 and dye 50 mg L‐1. Among the four ferrites CuFe2O4 was found to be best (k = 0.228 min‐1) which might be attributed to coupling between Fe3+/Fe2+ and Cu+/Cu2+ redox pairs thus generating more efficient Fenton reagent. Reusability of all the catalysts after magnetic separation was also tested over four cycles. CONCLUSION All the spinel ferrites had good photodegradation ability and recyclability demonstrating their use to remove organic pollutants from wastewater. © 2014 Society of Chemical Industry

CdS nanorod–MFe2O4 (M = Zn, Co and Ni) nanocomposites: a heterojunction synthesis strategy to mitigate environmental deterioration

“…band of MFe 2 O 4 (M=Zn, Co, Ni) is more negative as compared to CdS. The control experiments, without any photo-catalyst, showed no noticeable decomposition of RhB indicating good photo stability of dye as shown in our previous reports 35,36. The light irradiation results into the creation of photo-induced electrons and holes.The photo-induced holes move towards MFe 2 O 4 region and the photo-induced electrons drives in CdS region resulting into electron-hole separation.…”

“…Hence, photo activity of the samples decrease as the color of the samples darkened 35. Hence, as the color of the sample gets darker, the penetration of the visible light to the illuminated dye solution gets reduced due to the turbidity of the solution.…”

Activation of peroxymonosulfate with magnetic and recyclable Fe3 O4 @C/MnCo2 O4 nanocomposites for the decolorization of Acid Orange II

“…As one kind of typical organic pollutant, synthetic dyes have attracted much attention as they occur in wastewater effluents from many industrial processes. The strong color of dyes in the aquatic system has serious esthetic and ecological problems . Some dyes are also toxic, mutagenic and carcinogenic .…”

“…Owing to the characteristics of magnetic response and easy separation from the reaction system using external magnets, many iron‐based spinel type of bimetallic oxides such as MFe 2 O 4 (M = Mn, Fe, Cu, Co, Ni, etc.) have been reported with high activity in PMS activation for the oxidation of organic pollutants . The problem of metal leaching can also be reduced by the strong metal–metal bonding interactions in the spinel structures .…”

Magnetically Retrievable Modified Nickel Ferrite Nanoparticles: Efficient Catalytic Reduction of Nitroarenes and Photo-oxidation of Hazardous Dyes

“…8 and values given in Table. 4, the catalytic ability of all the MRNF's followed the order-NiM 0.2 Fe 1.8 O 4 (M=Mn > Cu > Co > Fe > Cr > Ni > Zn). Percent conversion was calculated using the equation described elsewhere 36 37,38 . The dramatic enhancement in the catalytic performance with the introduction of Mn and Cu ions has also been recognized by various research cohorts in different catalytic applications 16,20,39,40 .…”