scholarly journals Degradation Efficiency and Kinetics Analysis of an Advanced Oxidation Process Utilizing Ozone, Hydrogen Peroxide and Persulfate to Degrade the Dye Rhodamine B

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 974
Author(s):  
Piotr Zawadzki ◽  
Małgorzata Deska

In this study, the effectiveness of a rhodamine B (RhB) dye degradation process at a concentration of 20 mg/L in different advanced oxidation processes—H2O2/UV, O3/UV and PDS/UV—has been studied. The use of UV in a photo-assisted ozonation process (O3/UV) proved to be the most effective method of RhB decolorization (90% after 30 min at dye concentration of 100 mg/L). The addition of sulfate radical precursors (sodium persulfate, PDS) to the reaction environment did not give satisfactory effects (17% after 30 min), compared to the PDS/UV system (70% after 30 min). No rhodamine B decolorization was observed using hydrogen peroxide as a sole reagent, whereas an effect on the degree of RhB degradation was observed when UV rays strike the sample with H2O2 (33% after 30 min). The rhodamine B degradation process followed the pseudo-first-order kinetics model. The combined PDS/O3/UV process has shown 60% color removal after 30 min of reaction time at an initial dye concentration of 100 mg/L. A similar effectiveness was obtained by only applying ozone or UV-activated persulfate, but at a concentration 2–5 times lower (20 mg/L). The results indicated that the combined PDS/O3/UV process is a promising method for high RhB concentrations (50–100 mg/L) comparing to other alternative advanced oxidation processes.

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1813
Author(s):  
Aneta Sokol ◽  
Artur Ratkiewicz ◽  
Iwona Tomaszewska ◽  
Joanna Karpinska

Studies on kinetics of galaxolide (HHCB) degradation under influence of UV, simulated sunlight and some advanced oxidation processes (H2O2, UV/H2O2, and Vis/H2O2) were conducted. Galaxolide appeared to be a photolabile compound. The first-order kinetics model was assumed for all studied processes. It was observed that basic pH favored HHCB degradation. The influence of natural matrices (river water and artificial sweat) on direct photolysis of HHCB was examined. It was stated that the process of the photodegradation proceeded slower at the presence of each matrix. HHCB lactone was identified using the GC-MS technique. The recorded chromatograms showed that apart from the lactone, other degradation products were formed that we could not identify. In order to deeper understand the HHCB degradation process, DFT calculations were performed. The results pointed out that OH radicals play a key role in HHCB decomposition, which mainly proceeds via H abstractions as well as OH additions. It follows from the calculations that the visible light is sufficient to initiate the advanced oxidation processes (AOPs) under the oxidative conditions, whereas UV irradiation is needed to start decay with no oxidative agents.


1992 ◽  
Vol 27 (1) ◽  
pp. 23-42 ◽  
Author(s):  
William H. Glaze ◽  
Fernando Beltran ◽  
Tuula Tuhkanen ◽  
Joon-Wun Kang

Abstract Advanced oxidation processes (AOPs) have been defined as near-ambient temperature processes that involve the generation of highly reactive radical intermediates, especially the hydroxyl radical. These processes show promise for the destruction of hazardous organic substances in municipal and industrial wastes, in drinking water and in ultrapure water. Three types of AOPs are considered in this paper: catalyzed decomposition of ozone; ozone with hydrogen peroxide (Peroxone); and photolysis of hydrogen peroxide with ultraviolet radiation. Kinetic models for these processes are being developed based on known chemical and photochemical principles. The models take into account measured effects of radical scavengers such as bicarbonate; dose ratios of the oxidants or UV intensity; pH; and the presence of generic radical scavengers. The models are used to discuss two cases: oxidation of parts-per-million levels of nitrobenzene with ozone, Peroxone and peroxide/UV and oxidation of naphthalene and pentachlorophenol with peroxide/UV.


2020 ◽  
Vol 42 ◽  
pp. e9
Author(s):  
Alex Leandro Andrade de Lucena ◽  
Daniella Carla Napoleão ◽  
Hélder Vinícius Carneiro da Silva ◽  
Rayany Magali da Rocha Santana ◽  
Beatriz Galdino Ribeiro ◽  
...  

The existence of pharmaceuticals in nature is a growing environmental problem, turning necessary the use of efficient treatments for the degradation of these substances, as the advanced oxidation processes (AOPs). In this work the AOPs UV/H2O2 and photo-Fenton were applied to degrade the pharmaceuticals lamivudine and zidovudine in an aqueous solution using a bench reactor, composed of three UV-C lamps. It was verified that the UV/H2O2 process presented a degradation of 97.33 ± 0.14% for lamivudine and 93.90 ± 0.33% for zidovudine, after 180 min of treatment and for an initial concentratin of each pharmaceutical of  5 mg.L-1 and [H2O2] of 600 mg.L-1.  A methodology by artificial neural networks (ANNs) was used to model the photocatalytic process, with the MLP 7-23-2 ANN representing it well, and determining the relative importance (%) of each of the input variables for the pharmaceutical’s degradation process. Kinetic studies for the pharmaceutical degradation and the conversion of organic matter showed good adjustments to the pseudo first-order models with R2 raging from 0.9705 to 0.9980. Toxicity assays for the before treatment solution indicated that the seeds Lactuca sativa and Portulaca grandiflora showed growth inhibition whereas the post-treatment solution inhibited only the growth of Lactuca sativa.


1992 ◽  
Vol 27 (1) ◽  
pp. 69-96 ◽  
Author(s):  
William J. Cooper ◽  
Michael G. Nickelsen ◽  
David E. Meacham ◽  
Thomas D. Waite ◽  
Charles N. Kurucz

Abstract Advanced oxidation processes for the removal and destruction of hazardous organic chemicals in water and wastewater is a research area of increasing interest. Advanced oxidation processes generally consider the hydroxyl radical, OH-, the major reactive transient species. A novel process under development, utilizing high energy electrons, extends this concept to include the simultaneous formation of approximately equal concentrations of oxidizing and reducing species. Irradiation of aqueous solutions results in the formation of the aqueous electron, e−aq, hydrogen atoms, H-, and OH-. These reactive transient species initiate chemical reactions capable of destroying organic compounds in aqueous solution. This paper presents data on the removal of six common organic contaminants that have been studied at the Electron Beam Research Facility. The removal and the factors affecting removal were determined. This study focuses on halogenated ethenes, benzene and substituted benzenes. Removal is described in waters of different quality, including potable water, and raw and secondary wastewater. Removal efficiencies ranged from 85 to >99% and varied with water quality, solute concentration, dose and compound.


2013 ◽  
Vol 39 (2) ◽  
pp. 107-115 ◽  
Author(s):  
Barbara Pieczykolan ◽  
Izabela Płonka ◽  
Krzysztof Barbusiński ◽  
Magdalena Amalio-Kosel

Abstract Treatment of leachate from an exploited since 2004 landfill by using two methods of advanced oxidation processes was performed. Fenton’s reagent with two different doses of hydrogen peroxide and iron and UV/H2O2 process was applied. The removal efficiency of biochemically oxidizable organic compounds (BOD5), chemically oxidizable compounds using potassium dichromate (CODCr) and nutrient (nitrogen and phosphorus) was examined. Studies have shown that the greatest degree of organic compounds removal expressed as a BOD5 index and CODCr index were obtained when Fenton’s reagent with greater dose of hydrogen peroxide was used - efficiency was respectively 72.0% and 69.8%. Moreover, in this case there was observed an increase in the value of ratio of BOD5/CODCr in treated leachate in comparison with raw leachate. Application of Fenton’s reagent for leachate treatment also allowed for more effective removal of nutrients in comparison with the UV/H2O2 process.


2010 ◽  
Vol 55 (6) ◽  
pp. 2101-2115 ◽  
Author(s):  
Elena Guinea ◽  
José Antonio Garrido ◽  
Rosa María Rodríguez ◽  
Pere-Lluís Cabot ◽  
Conchita Arias ◽  
...  

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