title: Investigation of PAA/PVDF-NZVI hybrids for metronidazole removal: synthesis, characterization, and reactivity characteristics.
abstract: For the first time, the removal process of metronidazole (MNZ) from aqueous solutions over nano zerovalent iron (NZVI) encapsulated within poly(acrylic acid) (PAA)/poly(vinylidene fluoride) (PVDF) membranes was reported. The resultant composite (PPN) demonstrated high reactivity, excellent stability and reusability over the reaction course. Such excellent performance might be attributed to the presence of the charged carboxyl groups in PVDF membrane support, which could enhance NZVI dispersion and improve its longevity. Results showed that a lower initial concentration and higher reaction temperature facilitated the removal of MNZ by PPN, and that the acidic and neutral conditions generally exhibited more favorable effect on MNZ removal than the alkaline ones. Kinetics of the MNZ removal by PPN was found to follow a two-parameter pseudo-first-order decay model well, and the activation energy of the MNZ degradation by PPN was determined to be 30.49kJ/mol. The presence of chloride ions slightly enhanced the reactivity of PPN with MNZ, whereas sulfate ions inhibited its reactivity. In addition, MNZ degradation pathways by PPN were proposed based on the identified intermediates. This study suggests that PPN composite possessing excellent performance may be a promising functional material to pretreat antibiotic wastewaters.
authors: Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, PR China.
authors: Jiacheng
authors: J
authors: Yang
authors: Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, PR China. Electronic address: famdct@sohu.com.
authors: Xiangyu
authors: X
authors: Wang
authors: Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, PR China.
authors: Minping
authors: M
authors: Zhu
authors: School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors: Huiling
authors: H
authors: Liu
authors: School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors: Jun
authors: J
authors: Ma
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry; D008795:Metronidazole / Q000302:isolation & purification*; D011145:Polyvinyls / Q000737:chemistry*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D005465:Fluorocarbon Polymers
chemical_list: D000180:Acrylic Resins; D007501:Iron; D008795:Metronidazole; D011145:Polyvinyls; D014874:Water Pollutants, Chemical; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers; C006903:carbopol 940
keywords: Acrylic acid; Kinetics; Metronidazole; NZVI; PVDF; Reaction pathways