Journal ArticleDOI
Influence of pH on the formation of sulfate and hydroxyl radicals in the UV/peroxymonosulfate system.
TLDR
The formation of HO(•) and SO(4)(•-) in the UV/PMS system was confirmed mainly from the cooperation of the photolysis of PMS, the decay of peroxomonosulfate radical (SO(5)(•-)) and the conversion of SO(3)(•) to HO( •) by simulation and experimental results.Abstract:
The influence of pH on the degradation of refractory organics (benzoic acid, BA) in UV(254 nm)/Peroxymonosulfate (UV/PMS) system was investigated. The degradation of BA was significantly enhanced at the pH range of 8-11, which could not be explained only by the generally accepted theory that SO(4)(•-) was converted to HO(•) at higher pH. A hypothesis was proposed that the rate of PMS photolysis into HO(•) and SO(4)(•-) increased with pH. The hypothesis was evidenced by the measured increase of apparent-molar absorption coefficient of PMS (e(PMS), 13.8-149.5 M(-1)·cm(-1)) and photolysis rate of PMS with pH, and further proved by the increased quasi-stationary concentrations of both HO(•) and SO(4)(•-) at the pH range of 8-10. The formation of HO(•) and SO(4)(•-) in the UV/PMS system was confirmed mainly from the cooperation of the photolysis of PMS, the decay of peroxomonosulfate radical (SO(5)(•-)) and the conversion of SO(4)(•-) to HO(•) by simulation and experimental results. Additionally, the apparent quantum yield for SO(4)(•-) in the UV/PMS system was calculated as 0.52 ± 0.01 at pH 7. The conclusions above as well as the general kinetic expressions given might provide some references for the UV/PMS applications.read more
Citations
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Journal ArticleDOI
Generation of sulfate radical through heterogeneous catalysis for organic contaminants removal: Current development, challenges and prospects
TL;DR: In this paper, the authors provide a state-of-the-art review on the development in heterogeneous catalysts including single metal, mixed metal, and nonmetal carbon catalysts for organic contaminants removal, with particular focus on peroxymonosulfate (PMS) activation.
Journal ArticleDOI
Evaluation of advanced oxidation processes for water and wastewater treatment - A critical review.
TL;DR: Recommendations regarding the use of the EEO concept, including the upscaling of laboratory results, were derived from an extensive analysis of studies reported in the peer-reviewed literature enabling a critical comparison of various established and emerging AOPs based on electrical energy per order (EEO) values.
Journal ArticleDOI
Application of peroxymonosulfate and its activation methods for degradation of environmental organic pollutants: Review
Farshid Ghanbari,Mahsa Moradi +1 more
TL;DR: A literature review on environmental application of peroxymonosulfate (PMS) in degradation of contaminants to clarify the performance of PMS is carried out in this paper, which describes the PMS usage in remediation of environmental pollutants with focus on the different methods of activation and the effect of main operational parameters on PMS-based processes.
Journal ArticleDOI
Persulfate-Based Advanced Oxidation: Critical Assessment of Opportunities and Roadblocks.
TL;DR: This Critical Review comparatively examines the activation mechanisms of peroxymonosulfate and peroxydisulfates and the formation pathways of oxidizing species and the impacts of water parameters and constituents such as pH, background organic matter, halide, phosphate, and carbonate on persulfate-driven chemistry.
Journal ArticleDOI
Chemistry of persulfates in water and wastewater treatment: A review
Stanisław Wacławek,Holger V. Lutze,Klaudiusz Grübel,Vinod V.T. Padil,Miroslav Černík,Dionysios D. Dionysiou +5 more
TL;DR: In this paper, the authors provide an overview of various methods for analysis of persulfate decontamination and their analysis is often prone for interference by other matrix components and hampered by the low stability of peroxydisulfate and peroxymonosulfate in aqueous systems.
References
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Degradation of organic contaminants in water with sulfate radicals generated by the conjunction of peroxymonosulfate with cobalt.
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