Enhanced degradation of polyvinyl alcohol over a Cu0-carbon@γ-Al2O3 composite through heterogeneous Fenton-like reactions: Preparation, mechanism, and applications

Novel Fenton-like Catalyst HKUST-1(Cu)/MoS2-3-C with Non-Equilibrium-State Surface for Selective Degradation of Phenolic Contaminants: Synergistic Effects of σ-Cu-Ligand and ≡Mo–OOSO3− Complex

“…The proportion of Cu species is calculated by integration of the peak areas, which follows the order of Cu(II) (57.31%) > Cu(I) (35.09%) > Cu (7.60%). Herein, Cu(II) plays the dominant role in the formation of σ-Cu(II)-ligand, while Cu(I) can directly reduce oxidants with the generation of radicals [17]. Notably, binding energies of Cu 2p3/2 (932.9 eV) The proportion of Cu species is calculated by integration of the peak areas, which follows the order of Cu(II) (57.31%) > Cu(I) (35.09%) > Cu (7.60%).…”

“…Notably, binding energies of Cu 2p3/2 (932.9 eV) The proportion of Cu species is calculated by integration of the peak areas, which follows the order of Cu(II) (57.31%) > Cu(I) (35.09%) > Cu (7.60%). Herein, Cu(II) plays the dominant role in the formation of σ-Cu(II)-ligand, while Cu(I) can directly reduce oxidants with the generation of radicals [17]. Notably, binding energies of Cu 2p 3/2 (932.9 eV) and Cu 2p 1/2 (952.8 eV) in HKUST-1(Cu)/MoS 2 -3-C are higher than those in HKUST-1(Cu)-C (932.6 eV and 952.4 eV) (Figure S2), suggesting the strong interaction between Mo and Cu in HKUST-1(Cu)/MoS 2 -3-C [13,14].…”

Mineralization of Poly(vinyl alcohol) by Ozone Microbubbles under a Wide Range of pH Conditions

“…Poly­(vinyl alcohol) (PVA), one of the most important water-soluble polymers, is widely used as a sizing and coating agent, adhesive, and film. The annual global consumption of PVA in the past 20 years has been estimated to be hundreds of thousands of tons, and substantial amounts of PVA are discharged in industrial effluents . PVA is biostable and resistant to microorganism-mediated biodegradation, and the difficulty of PVA degradation reflects the complexity of dealing with PVA in industrial wastewater treatment. , The inability to degrade PVA sufficiently in wastewater treatment results in PVA entering aqueous environments, ultimately threatening the ecological systems.…”

“…In addition, PVA can enhance the mobilization of heavy metals from the sediments of natural water bodies, leading to the accumulation of toxic substances . Therefore, development of effective methods for removing PVA from wastewater has been a major challenge, and a considerable amount of research on PVA degradation has been carried out. − ,− Because the typical biological oxygen demand over 5 days/chemical oxygen demand ratio (BOD 5 /COD) of desizing wastewater (PVA = 1.5 g/L) is only 0.064, most previous studies have focused on the mineralization and/or improvement of the biodegradability of treated water. These methods are characteristically dependent on physicochemical processes, such as wet-air oxidation or advanced oxidation processes (AOPs), leading to the generation of strong oxidants, such as •OH or SO 4 •– . , Although these methods effectively degrade PVA and improve the treated water’s biodegradability, mineralization is strongly limited by the formation of recalcitrant intermediates, such as ketones and carboxylic acids. − , From an application point of view, it is desirable to pursue more cost-effective oxidation methods that provide the complete mineralization of PVA in solution.…”