TY - JOUR
T1 - New insights into heterogeneous generation and evolution processes of sulfate radicals for phenol degradation over one-dimensional α-MnO2 nanostructures
AU - Wang, Yuxian
AU - Indrawirawan, Stacey
AU - Duan, Xiaoguang
AU - Sun, Hongqi
AU - Ang, Ha Ming
AU - Tadé, Moses O.
AU - Wang, Shaobin
N1 - Funding Information:
The authors acknowledge the use of equipment, scientific and technical assistance of the Curtin University Electron Microscope Facility and Centre for Microscopy Characterization, which have been partially funded by the University, State and Commonwealth Governments . H.S. is grateful for the supports of Curtin Research Fellowship and Opening Project (KL13-02) of State Key Laboratory of Materials-Oriented Chemical Engineering, China.
Publisher Copyright:
© 2014 Elsevier B.V.
PY - 2015/4/5
Y1 - 2015/4/5
N2 - Heterogeneous activation of peroxymonosulfate (PMS) has become an attractive approach for catalytic oxidation since it can not only provide sulfate radicals as an alternative to hydroxyl radicals, but also avoid the metal toxicity in homogeneous catalysis. In this study, three one-dimensional (1D) α-MnO2 nanostructures, nanorods, nanotubes and nanowires, were fabricated by a one-pot hydrothermal method without addition of any surfactants. Shape-dependent performance of 1D α-MnO2 was observed in catalytic degradation of phenol solutions. The phenol oxidation can be described by a first-order kinetic model and the activation energies of phenol oxidation on three α-MnO2 materials were estimated to be 20.3, 39.3 and 87.1kJ/mol on nanowires, nanorods, and nanotubes, respectively. Both electron paramagnetic resonance (EPR) spectra and competitive radical tests were applied to investigate the PMS activation processes and to differentiate the major reactive species dominating the catalytic oxidation. The processes of PMS activation, evolution of sulfate radicals, and phenol degradation pathways were clearly illustrated.
AB - Heterogeneous activation of peroxymonosulfate (PMS) has become an attractive approach for catalytic oxidation since it can not only provide sulfate radicals as an alternative to hydroxyl radicals, but also avoid the metal toxicity in homogeneous catalysis. In this study, three one-dimensional (1D) α-MnO2 nanostructures, nanorods, nanotubes and nanowires, were fabricated by a one-pot hydrothermal method without addition of any surfactants. Shape-dependent performance of 1D α-MnO2 was observed in catalytic degradation of phenol solutions. The phenol oxidation can be described by a first-order kinetic model and the activation energies of phenol oxidation on three α-MnO2 materials were estimated to be 20.3, 39.3 and 87.1kJ/mol on nanowires, nanorods, and nanotubes, respectively. Both electron paramagnetic resonance (EPR) spectra and competitive radical tests were applied to investigate the PMS activation processes and to differentiate the major reactive species dominating the catalytic oxidation. The processes of PMS activation, evolution of sulfate radicals, and phenol degradation pathways were clearly illustrated.
KW - AOPs
KW - EPR
KW - Manganese oxides
KW - Phenol degradation
KW - Sulfate radicals
UR - http://www.scopus.com/inward/record.url?scp=84920717486&partnerID=8YFLogxK
U2 - 10.1016/j.cej.2014.12.066
DO - 10.1016/j.cej.2014.12.066
M3 - Article
AN - SCOPUS:84920717486
SN - 1385-8947
VL - 266
SP - 12
EP - 20
JO - Chemical Engineering Journal
JF - Chemical Engineering Journal
ER -