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1

Falcon, M., B. Peyrille, P. Reihac, J. N. Foussard e H. Debellefontaine. "Oxydation en voie humide de la pollution organique aqueuse par le peroxyde d'hydrogène Procédé « Wet Peroxide Oxidation » (WPO®) Étude de nouveaux catalyseurs". Revue des sciences de l'eau 6, n.º 4 (12 de abril de 2005): 411–26. http://dx.doi.org/10.7202/705183ar.

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Les effluents aqueux pollués par des matières organiques provenant d'industries chimiques présentent souvent une faible biodégradabilité. Dans certains domaines de concentration (DCO = 0,5 - 15 g/l), le procédé WPO® développé au laboratoire se substitue avantageusement à l'incinération pour traiter ce type d'effluents. La réaction, qui met en œuvre le réactif de Fenton à température élevée, conduit parfois à la formation de quantités importantes d'acides carboxyliques légers. Nous avons donc développé des systèmes catalytiques originaux remplaçant les sels de fer et conduisant à une oxydation totale des acides carboxyliques. Le système le plus efficace constitué de sels de fer, de cuivre et de manganèse permet d'obtenir, en 1 h à 100 °C, l'oxydation totale d'un mélange synthétique de ces acides (COT = 5 g/l) avec 1,5 fois la quantité de peroxyde théoriquement nécessaire à l'oxydation. Le catalyseur précipité et séparé en fin de traitement peut être recyclé et conserve la môme activité. Les unités industrielles permettant d'effectuer le traitement WPO® avec les nouveaux catalyseurs, recyclés ou non, seront similaires à celle déjà réalisée pour le traitement de « points noirs » industriels.
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2

Dia, Oumar, Patrick Drogui, Rino Dubé e Gerardo Buelna. "Utilisation des procédés électrochimiques et leurs combinaisons avec les procédés biologiques pour le traitement des lixiviats de sites d’enfouissement sanitaires - revue de littérature". Revue des sciences de l’eau 29, n.º 1 (16 de março de 2016): 63–89. http://dx.doi.org/10.7202/1035717ar.

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Les lixiviats des sites d’enfouissement sanitaires contiennent divers types de composés organiques et inorganiques susceptibles de polluer les milieux aquatiques s’ils ne sont pas convenablement traités. Depuis quelques années, on note une utilisation croissante des techniques électrochimiques, avec des résultats satisfaisants, pour le traitement des lixiviats. Parmi les avantages liés à l’utilisation de ces procédés, on peut citer : une faible emprise au sol, un temps de traitement court, une utilisation limitée, voire inexistante, de réactifs chimiques et une facilité d’automatisation. La capacité à traiter les composés organiques bioréfractaires et à augmenter la biodégradabilité de l’effluent constitue un atout majeur lors du traitement de certains types de lixiviats. Dans cette revue de littérature, un accent particulier est porté sur les trois procédés électrochimiques les plus utilisés pour le traitement des lixiviats, à savoir : l’électro-oxydation (EO), l’électro-Fenton (EF) et l’électrocoagulation (EC). Pour chacun des procédés, les différents paramètres opératoires qui influencent l’efficacité du traitement sont élucidés. D’une façon globale, les procédés électrochimiques sont influencés entre autres par l’intensité du courant appliqué, le type d’électrode utilisé, la distance interélectrodes, le temps de traitement, le pH et la conductivité du milieu. Le couplage des procédés électrochimiques et biologiques pour le traitement des lixiviats a été investigué. L’intégration de ces deux procédés permet d’augmenter les performances épuratoires tout en réduisant les coûts et les temps de traitement. Toutefois, des études approfondies sont nécessaires afin d’optimiser ces couplages et d’éclaircir l’influence du traitement biologique sur le traitement électrochimique et vice-versa.
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3

Yochelson, Ellis L., e Mikhail A. Fedonkin. "The type specimens (Middle Cambrian) of the trace fossil Archaeonossa Fenton and Fenton". Canadian Journal of Earth Sciences 34, n.º 9 (1 de setembro de 1997): 1210–19. http://dx.doi.org/10.1139/e17-097.

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The original description of Archaeonossa, from beds considered Early Cambrian but now dated as early Middle Cambrian, included at least two unrelated forms of trace fossils. The ichnogenus and the type ichnospecies are redefined, a lectotype is designated, and the type material is reiilustrated, along with topotype material from Yoho National Park, British Columbia. Although this trace fossil was originally attributed to movement by a gastropod, it is concluded, on the basis of restudy, that the type occurrence should not be used as evidence of activity by Gastropoda.
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4

Debellefontaine, H., P. Striolo, M. Chakchouk, J. N. Foussard e J. Besombes-Vailhe. "Nouveaux procédés d'oxydation chimique pour l'élimination des rejets aqueux phénolés". Revue des sciences de l'eau 5, n.º 4 (12 de abril de 2005): 555–72. http://dx.doi.org/10.7202/705147ar.

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Pour faire face au problème posé par les rejets aqueux chargés en phénol, deux procédés d'épuration par voie chimique sont proposés. Les deux méthodes font appel au peroxyde d'hydrogène. Celui-ci joue le rôle de promoteur de radicaux lors de l'oxydation de la charge organique par l'oxygène moléculaire dans le premier procédé qui s'inspire de la technique « Wet Air Oxidation » et constitue l'agent oxydant dans le second procédé intitulé « Wet Peroxide Oxidation ». L'introduction en continu de peroxyde d'hydrogène permet d'initier la réaction d'oxydation du phénol par l'oxygène moléculaire et de réduire considérable-ment les conditions de température et de pression de fonctionnement de la technique WAO classique. La réduction de la Demande Chimique en Oxygène de l'effluent dépasse 95 % à 160 °C en introduisant du peroxyde d'hydrogène à raison de 10 % de la quantité stoechiométrique nécessaire pour l'oxydation complète du phénol. Le second procédé consiste à utiliser l'oxydation par le peroxyde d'hydrogène en présence de fer ferreux (réactif de Fenton) dans des conditions de température (environ 120 °C) conduisant à un abattement important de la charge organique de l'effluent. A température élevée, la compétition entre la réaction de décomposition du peroxyde en oxygène moléculaire inactif et celle de décomposition en radicaux qui développent le processus d'oxydation engendre des conditions opératoires optimales pour lesquelles l'efficacité du procédé est maximale. Ces deux procédés apportent une solution technique satisfaisante pour traiter, avec un abattement important de la demande chimique en oxygène et du carbone organique, les effluents aqueux assez fortement chargés en composés phénolés.
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5

Rodríguez, Jaime, David Contreras, Carolina Parra, Juanita Freer, Jaime Baeza e Nelson Durán. "Pulp Mill Effluent Treatment by Fenton-Type Reactions Catalyzed by Iron Complexes". Water Science and Technology 40, n.º 11-12 (1 de dezembro de 1999): 351–55. http://dx.doi.org/10.2166/wst.1999.0732.

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Fenton reaction, which involves hydrogen peroxide and ferrous ion, has been proposed as an efficient option for effluent treatment. In this work, the treatment of a pulp bleaching effluent using Fenton-type reactions assisted by either, 2,3-dihydroxybenzoic acid (2,3-DHBA), 3,4-dihydroxybenzoic acid (3,4-DHBA) and 1,2-dihydroxybenzene (CAT), were studied. The treatment was evaluated by the removal of adsorbable organochloride compounds (AOX) and toxicity. Furthermore, the degradation of 2-chlorophenol and 4-chlorophenol in aqueous solutions were carried out, separately. Increase in oxidative activities of Fenton-type reactions mediated by the dihydroxybenzenes (DHBs) were found. These activities enhancement were related with a higher production of activated species by Fe/DHBs/H2O2, as indicted by chemiluminesce. The large decrease in AOX values and toxicity of the treated bleaching effluent by DHBs at pH 4.0 and 7.0 showed that 2,3-DHBA enhanced the activity of the Fenton reaction. The use of 3,4-DHBA and CAT resulted in loss of efficiencies of Fenton reaction to effluent treatment but not to pure chlorophenol solutions. At pH 7.0 lower efficiencies than those at pH 4.0 were achieved.
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6

Pech, Michel. "Réaction à l’article « le macronisme : un nouveau type sournois de populisme »". Humanisme N° 318, n.º 1 (5 de julho de 2018): 117–18. http://dx.doi.org/10.3917/huma.318.0117.

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7

Ponvert, C., e J. P. Jacquier. "Mécanismes de la réaction allergique du type immédiat : les connaissances indispensables". Revue Française d'Allergologie et d'Immunologie Clinique 43, n.º 5 (setembro de 2003): 327–29. http://dx.doi.org/10.1016/s0335-7457(03)00086-8.

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8

Richard-Greenblatt, Melissa, Barbara Stryjewska e Dale R. Kalina. "Réaction lépreuse de type 1 chez un homme de 50 ans". Canadian Medical Association Journal 196, n.º 38 (11 de novembro de 2024): E1299—E1300. http://dx.doi.org/10.1503/cmaj.240040-f.

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9

Gagné, J. M., P. Bouchard e A. Gleizes. "Section efficace de la réaction Penning pour les atomes". Canadian Journal of Physics 63, n.º 12 (1 de dezembro de 1985): 1506–12. http://dx.doi.org/10.1139/p85-251.

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The average cross section [Formula: see text] for the Penning reaction between Kr (1s5) and [Formula: see text] atoms has been obtained from a comparative study of Kr–U and Kr–Th gas combinations in a hollow-cathode-type generator. The experimental value obtained is 2,8 × 10−15 cm2 ± 50%.
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10

Stavarache, Carmen, B. Yim, M. Vinatoru e Y. Maeda. "Sonolysis of chlorobenzene in Fenton-type aqueous systems". Ultrasonics Sonochemistry 9, n.º 6 (novembro de 2002): 291–96. http://dx.doi.org/10.1016/s1350-4177(02)00088-3.

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11

De Angelis, Laura, e María Marta Fidalgo de Cortalezzi. "Improved membrane flux recovery by Fenton-type reactions". Journal of Membrane Science 500 (fevereiro de 2016): 255–64. http://dx.doi.org/10.1016/j.memsci.2015.11.042.

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12

Walling, Cheves. "Intermediates in the Reactions of Fenton Type Reagents". Accounts of Chemical Research 31, n.º 4 (abril de 1998): 155–57. http://dx.doi.org/10.1021/ar9700567.

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13

Co, Thanh Thien, Dinh Khoi Le, Van De Le e Thi Nhu Thuy Doan. "Preparation of Heterogeneous Fenton-Type Nano Catalysts and Their Application to Methylene Blue Degradation". Science and Technology Development Journal 23, n.º 4 (2 de dezembro de 2020): 764–70. http://dx.doi.org/10.32508/stdj.v23i4.2451.

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Introduction: Iron-based nanocatalysts are known as a new generation heterogeneous Fenton catalyst, replacing the traditional Fenton catalyst system which has many disadvantages in experimental processes and industrial applications. In this study, we focused on the preparation of iron nanoparticles and their use when embedded in traditional supports, as well as tested their catalytic activity by modified Fenton-type oxidation of methylene blue (MB) substrate. Method: Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), X-ray diffraction (XRD) and UV-vis were used for physio-chemical characterization of the catalysts. Results: Iron nanoparticles were obtained in the reduction of iron salt by sodium borohydride (NaBH4), with particle size in the range of 4-5 nm. Fe-X (X represents C, Bentonite, Al2O3, or ZnO) was synthesized in high yield and applied to the Fenton oxidation of MB; approximately 99% conversion was observed in the case of Fe-C. Conclusion: Supported iron nanoparticles are active catalysts for the oxidation of MB; however, there are limitations if pH is above 3.
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14

Camus, M., E. Hainaut-Wierzbicka, P. Levillain, J. P. Saulnier, L. Lopez e G. Guillet. "Réaction cutanée sévère avec mucite au cours d’une chimiothérapie de type MINE". Annales de Dermatologie et de Vénéréologie 138, n.º 4 (abril de 2011): 307–10. http://dx.doi.org/10.1016/j.annder.2010.11.011.

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15

Fajardo-Puerto, Edgar, Abdelhakim Elmouwahidi, Esther Bailón-García, Agustín Francisco Pérez-Cadenas e Francisco Carrasco-Marín. "From Fenton and ORR 2e−-Type Catalysts to Bifunctional Electrodes for Environmental Remediation Using the Electro-Fenton Process". Catalysts 13, n.º 4 (30 de março de 2023): 674. http://dx.doi.org/10.3390/catal13040674.

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Currently, the presence of emerging contaminants in water sources has raised concerns worldwide due to low rates of mineralization, and in some cases, zero levels of degradation through conventional treatment methods. For these reasons, researchers in the field are focused on the use of advanced oxidation processes (AOPs) as a powerful tool for the degradation of persistent pollutants. These AOPs are based mainly on the in-situ production of hydroxyl radicals (OH•) generated from an oxidizing agent (H2O2 or O2) in the presence of a catalyst. Among the most studied AOPs, the Fenton reaction stands out due to its operational simplicity and good levels of degradation for a wide range of emerging contaminants. However, it has some limitations such as the storage and handling of H2O2. Therefore, the use of the electro-Fenton (EF) process has been proposed in which H2O2 is generated in situ by the action of the oxygen reduction reaction (ORR). However, it is important to mention that the ORR is given by two routes, by two or four electrons, which results in the products of H2O2 and H2O, respectively. For this reason, current efforts seek to increase the selectivity of ORR catalysts toward the 2e− route and thus improve the performance of the EF process. This work reviews catalysts for the Fenton reaction, ORR 2e− catalysts, and presents a short review of some proposed catalysts with bifunctional activity for ORR 2e− and Fenton processes. Finally, the most important factors for electro-Fenton dual catalysts to obtain high catalytic activity in both Fenton and ORR 2e− processes are summarized.
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van Genuchten, Case M., e Jasquelin Peña. "Mn(II) Oxidation in Fenton and Fenton Type Systems: Identification of Reaction Efficiency and Reaction Products". Environmental Science & Technology 51, n.º 5 (14 de fevereiro de 2017): 2982–91. http://dx.doi.org/10.1021/acs.est.6b05584.

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Reeves-Latour1, Maxime. "Réaction sociale et criminalité en col blanc". Criminologie 49, n.º 1 (18 de abril de 2016): 123–52. http://dx.doi.org/10.7202/1036197ar.

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Depuis les premiers travaux de Sutherland sur le crime en col blanc, les études ont maintes fois révélé comment la criminalité des élites est soumise à l’indifférence récurrente du public, des médias et des autorités publiques. L’article cherche à réviser cette image persistante dans la documentation scientifique. Le texte retrace premièrement l’évolution des réprobations publiques et des tentatives de contrôle de ce type de criminalité au xxe siècle, aux États-Unis et au Canada. L’article propose ensuite de réviser la conception très réactive que les chercheurs entretiennent à propos des réformes issues des scandales et autres affaires. La deuxième section propose en ce sens un modèle intégratif qui permet de mieux saisir le caractère dynamique et contextualisé des réformes législatives et institutionnelles destinées à l’encadrement et au contrôle des délinquances en col blanc. Afin d’illustrer la fécondité du modèle proposé, la troisième section de l’article se penche sur l’analyse d’un récent scandale dans la province de Québec. Émergeant vers la fin des années 2000, ce dernier trouve son origine dans de vastes complots criminels recensés au sein du milieu de la construction de la province, dans lequel firmes en construction, firmes de génie-conseil et élus politiques furent impliqués dans divers actes de corruption, de trucage des appels d’offres et de manipulations frauduleuses. Il y est illustré que ce scandale s’inscrit dans une tendance plus générale de contrôle et de sensibilisation accrue du public envers les crimes en col blanc relevés au coeur de ce scandale. Alors que le mouvement provoque des réactions populaires et des réorganisations institutionnelles sans précédent dans la province, les opportunités liées au développement de ce champ de recherche encore négligé en criminologie apparaissent plus nombreuses que jamais pour le chercheur.
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18

Iuliano, L., D. Pratico, C. Alessandri e F. Violi. "The fenton-type OHo generating reaction activates human platelets". Thrombosis Research 61 (janeiro de 1991): 122. http://dx.doi.org/10.1016/0049-3848(91)90645-d.

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19

Parkhomchuk (Kuznetsova), E. V., M. P. Vanina e S. Preis. "The activation of heterogeneous Fenton-type catalyst Fe-MFI". Catalysis Communications 9, n.º 3 (março de 2008): 381–85. http://dx.doi.org/10.1016/j.catcom.2007.07.009.

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San-Pedro, Liliana, Roger Méndez-Novelo, Emanuel Hernández-Núñez, Manuel Flota-Bañuelos, Jorge Medina e Germán Giacomán-Vallejos. "Selection of the Activated Carbon Type for the Treatment of Landfill Leachate by Fenton-Adsorption Process". Molecules 25, n.º 13 (2 de julho de 2020): 3023. http://dx.doi.org/10.3390/molecules25133023.

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Sanitary landfill leachates usually have characteristics that depend on the region where they are generated and according to the age of the landfill, which is why a unique treatment for their sanitation has not been found. However, the adsorption preceded by the Fenton process has been proven to be highly efficient at removing contaminants. In this study, the adsorptive capacity of two types of activated carbon, granular and powdered, was analyzed to determine which was more efficient in the adsorption stage in the Fenton-adsorption process. Likewise, its behavior was analyzed using three isotherm models (Langmuir, Freundlich and Temkin), testing the raw leachate and the Fenton-treated one with both carbons. The adsorption that is carried out on the carbons is better adjusted to the Freundlich and Temkin models. It concludes that multilayers, through the physical adsorption, carry out the adsorption of pollutants on the surface of the carbons. The results show that, statistically, granular activated carbon is more efficient at removing chemical oxygen demand (COD), and powdered activated carbon removes color better. Finally, an adsorption column was designed for the Fenton-adsorption process that was able to remove 21.68 kgCOD/kg carbon. Removal efficiencies for color and COD were >99%.
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21

Yoon, J., S. Cho, Y. Cho e S. Kim. "The characteristics of coagulation of fenton reaction in the removal of landfill leachate organics". Water Science and Technology 38, n.º 2 (1 de julho de 1998): 209–14. http://dx.doi.org/10.2166/wst.1998.0141.

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The need to improve the Fenton process, which is one of the leachate treatment trains at Metropolitan Landfill in Korea was raised. This study was intended to compare the Fenton reaction with coagulation in removing landfill leachate organics of specific size. The organics fractionated by ultrafiltration and measured by TOC, were selected for evaluating the characteristics of the removal of organics. From this study it was found that the organic removal pattern in the Fenton reaction was quite similar to coagulation. Both reactions removed large leachate organics more readily and selectively. For example, coagulation removed 59~73% of organics larger than molecular weight (MW) of 500 and only up to 18% of organics less than MW of 500. On the other hand, the Fenton process removed 72-89% of organics larger than MW of 500 and only up to 43% of organics less than MW of 500. It was interpreted that the coagulation step in the Fenton process had a primary role in selective removal of leachate organics, though the Fenton reaction is not coagulation. However, since the efficiency of organic removal in the Fenton reaction was higher than coagulation, the Fenton process in Metropolitan Landfill leachate treatment process may be called “a type of enhanced coagulation”.
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Kuznetsova, E. V., E. N. Savinov, L. A. Vostrikova e G. V. Echevskii. "The catalytic and photocatalytic oxidation of organic substances using heterogeneous Fenton-type catalysts". Water Science and Technology 49, n.º 4 (1 de fevereiro de 2004): 109–16. http://dx.doi.org/10.2166/wst.2004.0234.

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This paper deals with catalytic and photocatalytic oxidation of organic substances using H2O2 over heterogeneous Fenton-type catalysts. In the study a series of Fe-containing catalysts was experienced. A zeolite named as FeZSM-5 was selected as the most active heterogeneous Fenton-type catalyst. The FeZSM-5 reported was prepared by hydrothermal crystallization in the presence of iron salt. In contrast to the homogeneous Fenton system the catalyst prepared had minimal, if any, leaching of iron ions, was stable during 30 catalytic runs and didnÕt lose its activity in the presence of complexing agents, e.g. P2O74-. The catalyst was active in oxidation of organic substances at pH from 1.5 to 8, maximum activity was observed at pH = 3. The FeZSM-5 effectively oxidized a simulant of the warfare agent, diethylnitrophenil phosphate, which is hardly detoxified by other methods. It appeared that the rate of oxidation of formic acid, ethanol and benzene over FeZSM-5 increased under the action of visible light (λ>436 nm), quantum efficiency being 0.06-0.14.
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Kumar, John Elisa, Tsungom Mulai, Wanshanlang Kharmawphlang, Rajeshwar Nath Sharan e Mihir Kumar Sahoo. "Decolourisation, mineralisation and detoxification of mixture of azo dyes using Fenton and Fenton-type advanced oxidation processes". Chemical Papers 74, n.º 9 (9 de abril de 2020): 3145–59. http://dx.doi.org/10.1007/s11696-020-01147-9.

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Niepce, JC, e G. Watelle. "Transformation structurale associée à la réaction de décomposition des hydroxydes de type brucite". Journal de Chimie Physique 87 (1990): 1285–306. http://dx.doi.org/10.1051/jcp/1990871285.

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Doumic, Lucila I., Gabriel Salierno, Cinthia Ramos, Patricia M. Haure, Miryan C. Cassanello e María A. Ayude. "“Soluble” vs. “insoluble” Prussian blue based catalysts: influence on Fenton-type treatment". RSC Advances 6, n.º 52 (2016): 46625–33. http://dx.doi.org/10.1039/c6ra06618f.

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Santos, Bebiana L. C., Pier Parpot, Olívia S. G. P. Soares, Manuel F. R. Pereira, Elisabetta Rombi, António M. Fonseca e Isabel Correia Neves. "Fenton-Type Bimetallic Catalysts for Degradation of Dyes in Aqueous Solutions". Catalysts 11, n.º 1 (30 de dezembro de 2020): 32. http://dx.doi.org/10.3390/catal11010032.

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Dye compounds are becoming a problematic class of pollutants for the environment, so it is important to develop stable catalysts for their elimination. First, several studies were performed with different Y zeolites (NaY, (NH4)Y and USY) in order to select the best support for the preparation of the bimetallic catalysts. In particular, NaY zeolite was used as the support for Fe, Cu and Mn metals to prepare mono and bimetallic Fenton-type catalysts by the ion exchange method. The catalysts were characterized by several techniques, such as chemical analysis, nitrogen physisorption, X-ray diffraction (XRD), scanning electron microscopy (SEM) and cyclic voltammetry studies. Characterization results revealed that the metals were successfully ion-exchanged within the NaY zeolite. The prepared catalysts were tested for the aqueous-phase degradation of dye compounds (Procion yellow (PY) and Tartrazine (Tar)) at atmospheric pressure and different temperatures, using H2O2 as the oxidant. All the investigated samples were found to be active in degrading the dyes through the Fenton-type process; however, the oxidation rate was found to be higher in the presence of the bimetallic catalysts. CuFe-NaY displays the best mineralization rate for PY oxidation while MnFe-NaY shows the highest activity for Tar degradation. This work may provide further insight into the design of Fenton-type bimetallic catalysts with improved catalytic properties for environmental remediation.
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Igarashi, Kintaro, Yoshimi Shoji, Emiko Sekine-Suzuki, Megumi Ueno, Ken-ichiro Matsumoto, Ikuo Nakanishi e Koji Fukui. "Importance of Locations of Iron Ions to Elicit Cytotoxicity Induced by a Fenton-Type Reaction". Cancers 14, n.º 15 (27 de julho de 2022): 3642. http://dx.doi.org/10.3390/cancers14153642.

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The impact of the site of the Fenton reaction, i.e., hydroxyl radical (•OH) generation, on cytotoxicity was investigated by estimating cell lethality in rat thymocytes. Cells were incubated with ferrous sulfate (FeSO4) and hydrogen peroxide (H2O2), or pre-incubated with FeSO4 and then H2O2 was added after medium was replaced to remove iron ions or after the medium was not replaced. Cell lethality in rat thymocytes was estimated by measuring cell sizes using flow cytometry. High extracellular concentrations of FeSO4 exerted protective effects against H2O2-induced cell death instead of enhancing cell lethality. The pre-incubation of cells with FeSO4 enhanced cell lethality induced by H2O2, whereas a pre-incubation with a high concentration of FeSO4 exerted protective effects. FeSO4 distributed extracellularly or on the surface of cells neutralized H2O2 outside cells. Cytotoxicity was only enhanced when the Fenton reaction, i.e., the generation of •OH, occurred inside cells. An assessment of plasmid DNA breakage showed that •OH induced by the Fenton reaction system did not break DNA. Therefore, the main target of intracellularly generated •OH does not appear to be DNA.
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28

Ayadi, Sameh, e Manef Abderrabba. "Étude DFT des réactions d’hydrogénation des cyclohéxènes disubstitués en position 2 et 3". Canadian Journal of Chemistry 88, n.º 7 (julho de 2010): 613–21. http://dx.doi.org/10.1139/v10-062.

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Dans ce travail, nous avons étudié théoriquement les réactions d’hydrogénation des cyclohéxènes disubstitués par une voie chimique par le (Z)-1,2-diazène (1) et le (E)-1,2-diazène (1′). Nous avons discuté de point de vue thermodynamique la possibilité et la stéréosélectivité de ces réactions. Les états de transition de la réaction entre les cyclohéxènes de type (2a–2c) et le (Z)-1,2-diazène (1) ont été déterminés.
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29

Ha, Bui Manh. "Oxidation of diazinon by homogeneous fenton process". Tạp chí Khoa học 16, n.º 3 (24 de setembro de 2019): 5. http://dx.doi.org/10.54607/hcmue.js.16.3.2466(2019).

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The degradation of aqueous diazinon from an aqueous solution using H2O2/Fe2+ process is performed in a 1L batch chemical reactor. The extent of diazinon degradation (20 mg/L) has been investigated from a known initial pH solution, temperature and catalyst type (Fe2+, Fe3+) and for various initial concentrations of diazinon, H2O2 and Fe2+. The degradation efficiency was obtained (90.82% and 90.63%) at pH 3 and 4 of the initial solution respectively while catalyst type and reaction temperature have a slight impact on the final degradation of diazinon. Efficiency of diazinon removal can be enhanced by increasing initial H2O2 concentration in the range of 70 to 150 mg/L and initial Fe2+ concentration in the range of 2 to 5 mg/L. The highest degradation efficiency obtained was 90.95% at initial diazinon concentration of 10 mg/L, H2O2=150 mg/L and Fe2+ = 5 mg/L. This study proved that Fenton process can be used for pretreatment of pesticide wastewater contaminated by diazinon before a biological treatment.
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30

Von Kruedener, Stephanie, Harald Schempp e Erich F. Elstner. "Gas chromatographic differentiation between myeloperoxidase activity and fenton-type oxidants". Free Radical Biology and Medicine 19, n.º 2 (agosto de 1995): 141–46. http://dx.doi.org/10.1016/0891-5849(94)00237-e.

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31

Sashkina, K. A., V. S. Labko, N. A. Rudina, V. N. Parmon e E. V. Parkhomchuk. "Hierarchical zeolite FeZSM-5 as a heterogeneous Fenton-type catalyst". Journal of Catalysis 299 (março de 2013): 44–52. http://dx.doi.org/10.1016/j.jcat.2012.11.028.

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32

Kuznetsova, E. V., E. N. Savinov, L. A. Vostrikova e V. N. Parmon. "Heterogeneous catalysis in the Fenton-type system FeZSM-5/H2O2". Applied Catalysis B: Environmental 51, n.º 3 (agosto de 2004): 165–70. http://dx.doi.org/10.1016/j.apcatb.2004.03.002.

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33

Doumic, Lucila I., Micaela Génova, Gregor Žerjav, Albin Pintar, Miryan C. Cassanello, Hernán E. Romeo e María A. Ayude. "Hierarchically structured TiO2-based composites for Fenton-type oxidation processes". Journal of Environmental Management 236 (abril de 2019): 591–602. http://dx.doi.org/10.1016/j.jenvman.2019.02.026.

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34

WALLING, C. "ChemInform Abstract: Intermediates in the Reactions of Fenton Type Reagents". ChemInform 29, n.º 30 (20 de junho de 2010): no. http://dx.doi.org/10.1002/chin.199830308.

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35

Ge, Fuxiang, Xuehua Li, Mian Wu, Hui Ding e Xiaobing Li. "A type II heterojunction α-Fe2O3/g-C3N4 for the heterogeneous photo-Fenton degradation of phenol". RSC Advances 12, n.º 14 (2022): 8300–8309. http://dx.doi.org/10.1039/d1ra09282k.

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36

Le Mignot, Virginie, Catherine Lièvre, Catherine Fréchou e Gilles Demailly. "Réaction de type Wittig sur des aldoses non protégés: Synthèse d'esters α,β-insaturés". Tetrahedron Letters 39, n.º 9 (fevereiro de 1998): 983–84. http://dx.doi.org/10.1016/s0040-4039(97)10721-3.

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37

Mallone, R. "Réaction auto-immune et diabète de type 1, que reste-t-il à découvrir ?" Annales d'Endocrinologie 75, n.º 5-6 (outubro de 2014): 252. http://dx.doi.org/10.1016/j.ando.2014.07.025.

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38

Fabre, J. M., D. Serhani, K. Saoud e A. K. Gouasmia. "Étude de La Synthèse de Tétrachalcogenofulvalenes Dissymétriquement Substitués Par Réaction de Type Wittig-Horner". Bulletin des Sociétés Chimiques Belges 102, n.º 9 (1 de setembro de 2010): 615–22. http://dx.doi.org/10.1002/bscb.19931020909.

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39

Abitbol, J., N. Abdelhedi-Mekki, C. Bertin, L. Deschamps, J. El Khalifa, C. De La Porte Des Vaux, J. Quelain et al. "Réaction de réversion à type de tuberculides papulo-nécrotiques au cours d’une tuberculose ganglionnaire". Annales de Dermatologie et de Vénéréologie - FMC 3, n.º 8 (dezembro de 2023): A229. http://dx.doi.org/10.1016/j.fander.2023.09.367.

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40

Belaid, Kumar Djamel, e Smaïl Kacha. "Étude cinétique et thermodynamique de l’adsorption d’un colorant basique sur la sciure de bois". Revue des sciences de l’eau 24, n.º 2 (4 de outubro de 2011): 131–44. http://dx.doi.org/10.7202/1006107ar.

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L'adsorption du colorant textile rouge basique Neutral Red (RBNR) sur la sciure du bois a été étudiée. La cinétique, la thermodynamique et les isothermes d'adsorption ont été utilisés pour identifier les mécanismes de la rétention. Les expériences, menées en réacteur fermé et parfaitement agité, pour la détermination de la cinétique, ont été réalisées après réglage des paramètres influençant le système, tels le pH, la masse d'adsorbant et la concentration initiale en colorant. Les résultats obtenus ont été modélisés suivant les équations cinétiques du pseudo-premier ordre, pseudo-second ordre, ainsi que ceux liés à la diffusion externe et intraparticulaire. Les résultats expérimentaux de la réaction globale sont parfaitement ajustables au pseudo-second ordre, avec de très grands coefficients de régression. La diffusion intraparticulaire est l'étape déterminante dans le processus d'adsorption au‑dela de 60 min de contact. La thermodynamique et les isothermes d'adsorption prédisent le passage d'une réaction de surface exothermique spontanée, de type chimiosorption, avec rétention des molécules de RBNR en monocouches organisées sur la surface de l'adsorbant.
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41

Canizales, Sebastian, Francisco Molina, Camilo Castro e Julio Saldarriaga. "Evaluation of mature landfill leachates Treatment systems: the case of the landfill Curva de Rodas (Medellín-Colombia)". Revista Facultad de Ingeniería Universidad de Antioquia, n.º 69 (20 de janeiro de 2014): 300–316. http://dx.doi.org/10.17533/udea.redin.18157.

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Leachates produced in the closed landfill Curva de Rodas in Medellin, Colombia are catalogued as mature leachates. These are characterized as poorly biodegradable waste containing organic compounds such as fulvic and humic acids, heavy metals, ammonia, nitrogen, and salts. In this paper five possible physicochemical leachate treatments are evaluated: adsorption with five types of granular activated carbon (GAC), adsorption with zeolite type A, Fenton oxidation, chemical precipitation by Ca(OH)2, and coagulationflocculation with aluminum sulfide type A. The treatments are compared in terms of their capacity to remove Chemical Oxygen Demand (COD) and color. GAC adsorption removals of up to 39% for COD and 50% for color were achieved. In the case of the adsorption with zeolite type A, negligible removals of COD and color were achieved (3% and 7% respectively). Removals using the Fenton oxidation and neutralization with NaOH reached up to 95% for COD and 97% for color. When additionally neutralized with raw leachate the removals were up to 79% for COD and 87% for color. Finally in the chemical precipitation tests, removals of 27% for COD and 63% for color were achieved. Clearly, Fenton oxidation was identified as the most appropriate treatment process.
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42

Uchman, Alfred, Radek Mikuláš e Andrew K. Rindsberg. "Mollusc trace fossils Ptychoplasma Fenton and Fenton, 1937 and Oravaichnium Plička and Uhrová, 1990: Their type material and ichnospecies". Geobios 44, n.º 4 (julho de 2011): 387–97. http://dx.doi.org/10.1016/j.geobios.2010.08.001.

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43

Yue, P. L., J. Y. Feng e X. Hu. "Photo-Fenton reaction using a nanocomposite". Water Science and Technology 49, n.º 4 (1 de fevereiro de 2004): 85–90. http://dx.doi.org/10.2166/wst.2004.0228.

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A laponite RD clay-based Fe nanocomposite (Fe-Lap-RD) has been synthesized by the so-called pillaring technique. The X-ray diffraction (XRD) results reveal that the Fe-Lap-RD mainly consists of Fe2O3 (maghemite) crystallites and Fe2SiO10(OH)2 (iron silicate hydroxide) crystallites, respectively. The photo-catalytic activity of the Fe-Lap-RD for the degradation of an organic azo dye Orange II is examined. It is found that the rate of mineralization of Orange II is slower than that of discoloration. Under optimal conditions, 100% color and 70% total organic carbon (TOC) of 0.2 mM Orange II can be removed in 45 and 90 minutes, respectively. In addition, the performance of a strongly acidic type of ion exchange resin based catalyst as a heterogeneous photo-Fenton catalyst for the degradation of salicylic acid is also discussed.
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44

Popovic, Ana, Sonja Milicevic, Vladan Milosevic, Branislav Ivosevic, Jelena Carapic, Vladimir Jovanovic e Dragan Povrenovic. "Fenton process in dispersed systems for industrial wastewater treatment". Chemical Industry 73, n.º 1 (2019): 47–62. http://dx.doi.org/10.2298/hemind181019005p.

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Industrial wastewater contains recalcitrant organic compounds with a very complex chemical structure, built of molecules with long chains of carbon atoms and attached different functional groups. Chemical or biological treatments used for removal of these compounds are being replaced with more efficient non-commercial wastewater treatments. Advanced oxidation processes overcome limitations of conventional methods regarding formation of by-products during degradation of recalcitrant organic compounds. The Fenton process, or use of the Fenton?s reagent, has became one of the most utilized processes due to simplicity, economy and accessible amounts of ferrous iron and hydrogen-peroxide, which are used in the process. In specific, the Fenton?s reagent is a catalytic-oxidative mixture of these two components. The ferrous iron Fe2+ initiates and catalyzes decomposition of H2O2, resulting in generation of hydroxyl radicals, which are the main radical species in the process able to detoxify several organic pollutants by oxidation. In addition, other mechanisms besides formation of hydroxyl radicals may occur during the Fenton process and participate in degradation of target pollutants. Generally, the treatment efficiency relies upon the physical and chemical properties of target pollutants and the process operating conditions. The main disadvantage of the Fenton process is production of sludge formed by iron hydroxide at certain pH values. An alternative solution for this problem is application of this process in fluidized bed reactors. This paper presents an overview of Fenton and photo-Fenton processes in dispersed systems for removal of different industrial wastewater pollutants. The most important process parameters, required for efficient degradation of recalcitrant organic compounds are also described, such as the catalyst type, pH value, temperature, H2O2 concentration and retention time. Strict control of Fenton process parameters in fluidized bed reactors at desired values can bring these systems to the commercial use.
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45

Guo, Li, Kailai Zhang, Xuanxuan Han, Qiang Zhao, Danjun Wang e Feng Fu. "2D In-Plane CuS/Bi2WO6 p-n Heterostructures with Promoted Visible-Light-Driven Photo-Fenton Degradation Performance". Nanomaterials 9, n.º 8 (11 de agosto de 2019): 1151. http://dx.doi.org/10.3390/nano9081151.

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Photo-Fenton degradation of pollutants in wastewater is an ideal choice for large scale practical applications. Herein, two-dimensional (2D) in-plane CuS/Bi2WO6 p-n heterostructures have been successfully constructed by an in situ assembly strategy and characterized using XRD, XPS, SEM/TEM, EDX, UV-Vis-DRS, PL, TR-PL, ESR, and VB-XPS techniques. The XPS and the TEM results confirm the formation of CuS/Bi2WO6 heterostructures. The as-constructed CuS/Bi2WO6 showed excellent absorption in visible region and superior charge carrier separation efficiency due to the formation of a type-II heterojunctions. Under visible light irradiation, 0.1% CuS/Bi2WO6 heterostructure exhibited the best photo-Fenton-like catalytic performance. The degradation efficiency of Rhodamine B (RhB, 20 mg·L−1) can reach nearly 100% within 25 min, the apparent rate constant (kapp/min−1) is approximately 40.06 and 3.87 times higher than that of pure CuS and Bi2WO6, respectively. The degradation efficiency of tetracycline hydrochloride (TC-HCl, 40mg·L−1) can reach 73% in 50 min by employing 0.1% CuS/Bi2WO6 heterostructure as a photo-Fenton-like catalyst. The promoted photo-Fenton catalytic activity of CuS/Bi2WO6 p-n heterostructures is partly ascribed to its low carriers recombination rate. Importantly, CuS in CuS/Bi2WO6 heterostructures is conducive to the formation of heterogeneous photo-Fenton catalytic system, in which Bi2WO6 provides a strong reaction site for CuS to avoid the loss of Cu2+ in Fenton reaction, resulting in its excellent stability and reusability. The possible photo-Fenton-like catalytic degradation mechanism of RhB and TC-HCl was also elucidated on the basis of energy band structure analysis and radical scavenger experiments. The present study provides strong evidence for CuS/Bi2WO6 heterostructures to be used as promising candidates for photo-Fenton treatment of organic pollutants.
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46

Zhang, Guoyang, Shuo Lu, Chun Zhang, Bingdang Wu, Yong Liang, Zhihao Chen, Li Zhang e Shujuan Zhang. "Metal-free generation of hydroxyl radicals by benzoate-mediated decomposition of peroxides". Chemical Communications 56, n.º 54 (2020): 7443–46. http://dx.doi.org/10.1039/d0cc02633f.

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47

Wang, Jiaojiao, Xiaoqing Jia, Denghui Shang, Liangbo Xie, Yi Li, He Zhang, Sihui Zhan e Wenping Hu. "Constructing Cu2O/Bi2MoO6 p–n heterojunction towards boosted photo-assisted-electro-Fenton-like synergy degradation of ciprofloxacin". Environmental Science: Nano 8, n.º 12 (2021): 3629–42. http://dx.doi.org/10.1039/d1en00894c.

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48

Prato-Garcia, D., e G. Buitrón. "Solar photoassisted advanced oxidation process of azo dyes". Water Science and Technology 59, n.º 5 (1 de março de 2009): 965–72. http://dx.doi.org/10.2166/wst.2009.071.

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Advanced oxidation processes assisted with natural solar radiation in CPC type reactors (parabolic collector compound), was applied for the degradation of three azo dyes: acid orange (AO7), acid red 151 (AR151) and acid blue 113 (AB113). Fenton, Fenton like and ferrioxalate-type complexes showed to be effective for degrade the azo linkage and moieties in different extensions. Initially, the best dose of reagents (Fe3 + -H2O2) was determined through a factorial experimental design, next, using response surface methodologies, the reagent consumption was reduced up to 40%, maintaining in all cases high decolourisation percentages (>98%) after 60 min. of phototreatment. In this work, it was also studied the effect of concentration changes of the influent between 100–300 mg/L and the operation of the photocatalytic process near neutral conditions (pH 6.0–6.5) by using ferrioxalate type complex (FeOx).
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49

Kishimoto, Naoyuki, Takuya Kitamura e Yu Nakamura. "Applicability of an electrochemical Fenton-type process to actual wastewater treatment". Water Science and Technology 72, n.º 6 (4 de junho de 2015): 850–57. http://dx.doi.org/10.2166/wst.2015.279.

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The applicability of an electrochemical Fenton-type process (EF-HOCl-ReFe) to the treatment of three actual wastewaters, namely wastewater from an automobile factory (automobile wastewater), metal scrap-cleansing wastewater, and municipal wastewater, is discussed in this research. The EF-HOCl-ReFe successfully removed the chemical oxygen demand (COD) from automobile wastewater pre-treated by a coagulation process without any inhibition. The apparent current efficiency reached 86%, 46% of which was ascribed to the electrochemical Fenton-type mechanism. The metal scrap-cleansing wastewater had a yellow colour and high concentrations of COD (6550 mg/L) and Cl− (1560 mM). The EF-HOCl-ReFe could achieve almost complete COD removal and decolourization after 48 h of treatment, although a temporary intensification of colour was observed before the decolourization. The EF-HOCl-ReFe was also effective in the removal of 1,4-dioxane from municipal wastewater pre-treated by activated sludge and coagulation processes, which were unable to remove 1,4-dioxane. The 1,4-dioxane removal efficiency after 30 min of treatment reached 68.5%. Thus, the EF-HOCl-ReFe was applicable to the treatment of these actual wastewaters.
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50

Hartmann, Martin, Simon Kullmann e Harald Keller. "Wastewater treatment with heterogeneous Fenton-type catalysts based on porous materials". Journal of Materials Chemistry 20, n.º 41 (2010): 9002. http://dx.doi.org/10.1039/c0jm00577k.

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