A facile synthesis of metal ferrites and their catalytic removal of toxic nitro-organic pollutants

• Published in: Environmental pollution (1987) 2021-02, Vol.270, p.116063, Article 116063
• Main Authors: Ramu, A.G., Salla, Sunitha, Chandrasekaran, Sivaraman, Silambarasan, P., Gopi, S., Seo, Seung-yoon, Yun, Kyusik, Choi, Dongjin
• Format: Article
• Language: English
• Subjects: Aminophenol; Catalysis; Catalytic removal; Environmental Pollutants; Ferric Compounds; Metal ferrites; Nitrophenol; Photoelectron Spectroscopy; Waste water
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2020.116063

Nitrocompounds are the major prime water contaminants. In this investigative study, toxic nitrocompounds (4-nitrophenol, 2,4-dinitrophenol, 2,4,6-trinitrophenol) were removed by using magnetic CuFe2O4, CoFe2O4, and NiFe2O4 material systems. The metal ferrites were synthesized through hydrothermal method and also followed with calcination process. The properties of metal ferrites were confirmed through using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM) studies and results there on were presented. For the first time, the synthesized CuFe2O4, CoFe2O4, and NiFe2O4 material systems were used for the reduction of 4-nitrophenol (NP), 2,4-dinitrophenol (DNP), and 2,4,6-trinitrophenol (TNP) in aqueous medium. The UV–visible spectrometry was employed to monitor the removal of nitro compounds and formation of aminophenol. Among, the three catalysts, the CuFe2O4 displayed excellent removal activity for nitrocompounds. The CuFe2O4 nanoparticles completely removed the NP, DNP and TNP within 2, 5, 10 min, respectively. The NP reduction reaction follows the pseudo-first-order kinetics. Further, the investigated and proposed CuFe2O4, catalyst has given and demonstrated excellent kinetic rate constants 0.990, 0.317, 0.184 min−1 for 4-NP, DNP and TNP respectively, which was very fast kinetic than the already published reports. Also, the aminophenol formation was confirmed for the above mentioned and select nitrocompounds. The obtained results confirm suggest that CuFe2O4 nanoparticles based material system could be one of the promising catalysts for nitro compounds removal process. [Display omitted] •Metal ferrites were synthesized through hydrothermal combined calcination process.•MFe2O4 (M- Cu, Co, Ni) catalyst was applied for the nitro compounds reduction.•CuFe2O4 showed better activity towards 4-NP, 2,4-DNP and 2,4,6-TNP reduction.•CuFe2O4 completes the reduction of 4-NP, 2,4-DNP and 2,4,6-TNP within 2, 5, 10 min.•CuFe2O4 reduced three nitro compounds with the rates of 0.99, 0.31, and 0.184. This work investigates the unique features of toxic nitro-organic pollutants removal of metal ferrites.