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Partager le résultat de cette recherche Interroger des sources externesElimination des polluants organiques par méthodes physicochimiques et photochimiques en milieux aqueux. / Abdessemed Ala
Titre : Elimination des polluants organiques par méthodes physicochimiques et photochimiques en milieux aqueux. : Cas de l’éthyle violet et du rouge congo (séparés et mélangés) et de la monochloramine Type de document : texte imprimé Auteurs : Abdessemed Ala, Auteur ; Kamel Djebbar, Auteur Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 224 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Éthyle Violet Rouge Congo Mochloramine TiO2 Charbon actif ZnO Adsorption Rayonnement UV Photolyse H2O2 NaOCl •OH Ethyl violet Congo red Monochloramine Activated carbon UV radiation Photolysis Violet Ethyle) (Congo Rouge) المونوكلرمين (NH2Cl) (PC500 TiO2) كربون منشط (ZnO) إدمصاص أشعة فوق بنفسجية (H2O2) (NaOCl) (•OH ) (•Cl) Index. décimale : 540 Chimie et sciences connexes Résumé : The aim of this research is to study the decolorization of two dyes separated and in a mixture by physico-chemical processes (adsorption, TiO2 and CA-ZnO) and photocatalytic processes like: TiO2/UV and CA-ZnO/UV. Another study has been led on the degradation of Monocloramine in homogeneous phase via direct UV photolysis, H2O2/UV and
NaOCl/UV. Treated separately, both dyes have shown an appreciable adsorption on the two supports and that this process is well represented by an apparent kinetic of order 2.
Besides, Congo Red and Ethyl Violet are described by isotherms of type L and S respectively and that process is also well represented by the model of Langmuir for Ethyl Violet and Redlish-Peterson of Congo Red. On the other hand, the photocatalytic system led via TiO2/UV has been efficient toward both dyes and this process follows an apparent
rate constant of order 1. In another part, this process is well described by the kinetic model of Langmuir-Hinshelwood and that oxidation process occurs, mainly, in surface. The inhibition process has been demonstrated by alcohols proving thereby that radicals •OH are the main oxidation route. The photoproducts issued from the decolorization of the two dyes have been identified using masse spectroscopy technic. This has permitted to establish a mechanism of degradation for the two dyes. Same efficiency is obtained using CAZnO/UV process (CA: activated carbon issued from olive cakes). In another side and in the mixture, the treatment of the two dyes by both systems has, shown that the efficiency decreases as the concentration of the other added dye increases. Indeed, the addition of the second substrate slows down the disappearance speed of the other. The kinitics model
remained unchanged for the two processes (2nd order for adsorption and 1 st order for photocatalysis) The last part treats the degradation of the Monochloramine which occurs via direct UV photolysis in presence of two lamps:
BP (254 nm) and MP (200-600 nm).
The obtained results have been significant. Furthermore, these results have been greatly enhanced mainly by H2O2/UV. However, for NaOCl/UV system we could mention that the disappearance rate slows down because of the formation of photoproducts such as: Mono, Di and Trichloramines. Moreover, the process is well described by an apparent kinetic of order 1 and those photoproducts identified in H2O2/UV, NaOCl/UV and direct photolysis systems are nitrates and nitritesDiplôme : Doctorat en sciences En ligne : ../theses/chimie/ALA6959.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10358 Elimination des polluants organiques par méthodes physicochimiques et photochimiques en milieux aqueux. : Cas de l’éthyle violet et du rouge congo (séparés et mélangés) et de la monochloramine [texte imprimé] / Abdessemed Ala, Auteur ; Kamel Djebbar, Auteur . - جامعة الإخوة منتوري قسنطينة, 2016 . - 224 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Éthyle Violet Rouge Congo Mochloramine TiO2 Charbon actif ZnO Adsorption Rayonnement UV Photolyse H2O2 NaOCl •OH Ethyl violet Congo red Monochloramine Activated carbon UV radiation Photolysis Violet Ethyle) (Congo Rouge) المونوكلرمين (NH2Cl) (PC500 TiO2) كربون منشط (ZnO) إدمصاص أشعة فوق بنفسجية (H2O2) (NaOCl) (•OH ) (•Cl) Index. décimale : 540 Chimie et sciences connexes Résumé : The aim of this research is to study the decolorization of two dyes separated and in a mixture by physico-chemical processes (adsorption, TiO2 and CA-ZnO) and photocatalytic processes like: TiO2/UV and CA-ZnO/UV. Another study has been led on the degradation of Monocloramine in homogeneous phase via direct UV photolysis, H2O2/UV and
NaOCl/UV. Treated separately, both dyes have shown an appreciable adsorption on the two supports and that this process is well represented by an apparent kinetic of order 2.
Besides, Congo Red and Ethyl Violet are described by isotherms of type L and S respectively and that process is also well represented by the model of Langmuir for Ethyl Violet and Redlish-Peterson of Congo Red. On the other hand, the photocatalytic system led via TiO2/UV has been efficient toward both dyes and this process follows an apparent
rate constant of order 1. In another part, this process is well described by the kinetic model of Langmuir-Hinshelwood and that oxidation process occurs, mainly, in surface. The inhibition process has been demonstrated by alcohols proving thereby that radicals •OH are the main oxidation route. The photoproducts issued from the decolorization of the two dyes have been identified using masse spectroscopy technic. This has permitted to establish a mechanism of degradation for the two dyes. Same efficiency is obtained using CAZnO/UV process (CA: activated carbon issued from olive cakes). In another side and in the mixture, the treatment of the two dyes by both systems has, shown that the efficiency decreases as the concentration of the other added dye increases. Indeed, the addition of the second substrate slows down the disappearance speed of the other. The kinitics model
remained unchanged for the two processes (2nd order for adsorption and 1 st order for photocatalysis) The last part treats the degradation of the Monochloramine which occurs via direct UV photolysis in presence of two lamps:
BP (254 nm) and MP (200-600 nm).
The obtained results have been significant. Furthermore, these results have been greatly enhanced mainly by H2O2/UV. However, for NaOCl/UV system we could mention that the disappearance rate slows down because of the formation of photoproducts such as: Mono, Di and Trichloramines. Moreover, the process is well described by an apparent kinetic of order 1 and those photoproducts identified in H2O2/UV, NaOCl/UV and direct photolysis systems are nitrates and nitritesDiplôme : Doctorat en sciences En ligne : ../theses/chimie/ALA6959.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10358 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité ALA/6959 ALA/6959 Thèse Bibliothèque principale Thèses Disponible
Titre : Reactivite des complexes organiques de Fer(III) vis-a-vis de produits pharmaceutiques en solution aqueuse en presence de lumiere naturelle et simulee. Type de document : texte imprimé Auteurs : Besma Anfal Dekkiche, Auteur ; Nadra Debbache, Directeur de thèse Mention d'édition : 14 Juillet 2019 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 178 f. Format : 30 cm. Note générale : Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Chimie:Chimie Analytique et Environnement Fe(III)malonate Fe(III)malate ibuprofène •OH •CH2COOH ibuprofen •CH2COOH. ايبوبروفن الجذر•OH الجذر•CH2COOH Index. décimale : 540 Chimie et sciences connexes Résumé : The photolysis of iron(III) organic complexes in the presence of natural and simulated light was a concern for the role it plays within the environment in terms of producing hydroxyl radicals able to degrade organic products. A first part was devoted to the synthesis and characterization of iron(III) organic complexes in aqueous solution namely Fe(III)malate and Fe(III)malonate. Under light irradiation, the photolysis of the Fe(III) malate complex produced •OH radical and H2O2, however, in the case of Fe(III)malonate, •CH2COOH radical is generated without formation of H2O2. In the second part of the work, IBP was used as a model molecule to study the behavior of iron(III) organic complexes towards this pollutant. A preliminary study of the mixture complex/IBP in the dark and at room temperature was performed and confirmed the absence of interaction between the substrate and the complexes. Under irradiation at 365nm, the evolution of the mixtures complex/IBP demonstrated the disappearance of the substrate. The influence of several factors, such as pH, concentration of the complex and the substrate, oxygen and the excitation wavelength, on the photodegradation of IBP has been demonstrated. The mineralization of IBP required more time than photodegradation. The study of the mixture complex/IBP/H2O2 was compared with the previous system in kinetic
and mechanistic terms and shows an improvement in the reaction rate by the supply of H2O2 in concentration ranging from (10-4 to 10-2M). The optimization of H2O2 dose depends on the complex where 5×10-3M is the ideal concentration for Fe(III)malate, however, it is restricted 10-3M in the case of Fe(III)malonate in acidic medium (pH = 2.8). The mechanistic aspect was also taken into account and shows the role of the oxidative radicals involved in the photochemical process which would involve the radical •OH for the Fe(III)malate then the conjugated effect of the radicals •CH2COOH and •OH particularise the case of Fe(III)malonate. In the combined system an additional production of •OH improved the performance of the previous system. Seven photoproducts were identified by HPLC-MS during the irradiation of the Fe(III)MO/IBP mixture under irradiation at 365nm and the corresponding reaction mechanism was proposed. Experiments in the natural environment have been carried out under natural irradiation and show the feasibility of the photochemical process in the environment. In addition, the presence of certain elements present in aquatic environment such as humic substances and metals have been examined and reveal the influence of these elements on the photochemical process.
Diplôme : Doctorat En ligne : ../theses/chimie/DEK7570.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11408 Reactivite des complexes organiques de Fer(III) vis-a-vis de produits pharmaceutiques en solution aqueuse en presence de lumiere naturelle et simulee. [texte imprimé] / Besma Anfal Dekkiche, Auteur ; Nadra Debbache, Directeur de thèse . - 14 Juillet 2019 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 178 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Chimie:Chimie Analytique et Environnement Fe(III)malonate Fe(III)malate ibuprofène •OH •CH2COOH ibuprofen •CH2COOH. ايبوبروفن الجذر•OH الجذر•CH2COOH Index. décimale : 540 Chimie et sciences connexes Résumé : The photolysis of iron(III) organic complexes in the presence of natural and simulated light was a concern for the role it plays within the environment in terms of producing hydroxyl radicals able to degrade organic products. A first part was devoted to the synthesis and characterization of iron(III) organic complexes in aqueous solution namely Fe(III)malate and Fe(III)malonate. Under light irradiation, the photolysis of the Fe(III) malate complex produced •OH radical and H2O2, however, in the case of Fe(III)malonate, •CH2COOH radical is generated without formation of H2O2. In the second part of the work, IBP was used as a model molecule to study the behavior of iron(III) organic complexes towards this pollutant. A preliminary study of the mixture complex/IBP in the dark and at room temperature was performed and confirmed the absence of interaction between the substrate and the complexes. Under irradiation at 365nm, the evolution of the mixtures complex/IBP demonstrated the disappearance of the substrate. The influence of several factors, such as pH, concentration of the complex and the substrate, oxygen and the excitation wavelength, on the photodegradation of IBP has been demonstrated. The mineralization of IBP required more time than photodegradation. The study of the mixture complex/IBP/H2O2 was compared with the previous system in kinetic
and mechanistic terms and shows an improvement in the reaction rate by the supply of H2O2 in concentration ranging from (10-4 to 10-2M). The optimization of H2O2 dose depends on the complex where 5×10-3M is the ideal concentration for Fe(III)malate, however, it is restricted 10-3M in the case of Fe(III)malonate in acidic medium (pH = 2.8). The mechanistic aspect was also taken into account and shows the role of the oxidative radicals involved in the photochemical process which would involve the radical •OH for the Fe(III)malate then the conjugated effect of the radicals •CH2COOH and •OH particularise the case of Fe(III)malonate. In the combined system an additional production of •OH improved the performance of the previous system. Seven photoproducts were identified by HPLC-MS during the irradiation of the Fe(III)MO/IBP mixture under irradiation at 365nm and the corresponding reaction mechanism was proposed. Experiments in the natural environment have been carried out under natural irradiation and show the feasibility of the photochemical process in the environment. In addition, the presence of certain elements present in aquatic environment such as humic substances and metals have been examined and reveal the influence of these elements on the photochemical process.
Diplôme : Doctorat En ligne : ../theses/chimie/DEK7570.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11408 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité DEK/7570 DEK/7570 Thèse Bibliothèque principale Thèses Disponible
