Efficient oxidative degradation of chlorophenols by using magnetic surface carboxylated Cu0/Fe3O4 nanocomposites in a wide pH range. Issue 3 (June 2017)

• Record Type: Journal Article
• Authors: Ding, Yaobin; Ruan, Yufeng; Zhu, Lihua; Tang, Heqing
• Is Part Of: Journal of environmental chemical engineering. Volume 5:Issue 3(2017:Sep.)
• Page Start: 2681
• Page End: 2690
• Publication Date: 2017-06
• Subjects: Catalytic activation -- Molecular oxygen -- Surface carboxyl groups -- Cu–Fe composite -- Oxidative degradation -- Chlorophenols; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2017.05.021
• Languages: English
• ISSNs: 2213-2929

Abstract

Graphical abstract: Highlights: Surface carboxylated Cu 0 /Fe3 O4 nanocomposites were successfully prepared. Cu 0 /Fe3 O4 could activate molecular oxygen toward degradation of chlorophenols. Cu 0 /Fe3 O4 exhibited highly catalytic activity in a wide pH range from 3.0 to 10.0. The generation of O2 −, H2 O2, and OH over Cu 0 /Fe3 O4 was evidenced and tracked. The activation of O2 was confirmed to be synergistically initiated by Cu 0 and Fe3 O4 . Abstract: Surface carboxylated Cu 0 /Fe3 O4 nanocomposites were prepared and used as a heterogeneous catalyst for activating molecular oxygen toward degradation of chlorophenols. The use of 1.0 g L −1 Cu 0 /Fe3 O4 composites yielded a nearly complete removal of 4-chlorophenol (4-CP, 0.1 mmol L −1 ) in 60 min in a wide pH range from 3.0 to 10.0. The pseudo first rate constant ( k ) for 4-CP degradation at pHinitial 7.0 in the system of Cu 0 /Fe3 O4 -Air was 0.073 min −1, being 10.9 and 7.3 times that obtained in the systems of alone Cu 0 and Fe3 O4 nanoparticles, respectively. The generation of O2 −, H2 O2, and OH as reactive oxygen species from the catalytic activation of O2 over the Cu 0 /Fe3 O4 composites was evidenced and tracked. The activation of dissolved oxygen was confirmed to be synergistically initiated by the simultaneous use of strongly-interacted Cu 0 and Fe3 O4 nanoparticles, where the surface carboxyl groups mediated fast reduction of Fe(III) back to Fe(II) in Fe3 O4 domains by Cu 0 as a reducing agent. The present study not only sheds light on the synergistic effect between bimetal oxides in the environmental catalytic processes, but also provides a facile and efficient chemical method for the oxidative removal of organic pollutants.