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Partager le résultat de cette recherche Interroger des sources externesComportements thermique et photochimique du paracétamol et de l’aspirine par la goethite en solution aqueuse en phase hétérogène / Yazid Mameri
Titre : Comportements thermique et photochimique du paracétamol et de l’aspirine par la goethite en solution aqueuse en phase hétérogène Type de document : texte imprimé Auteurs : Yazid Mameri, Auteur ; Nadra Debbache, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 177 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Paracétamol Aspirine Photodégradation Radicaux hydroxyle Goethite Fenton Paracetamol Aspirin Photodegradation Hydroxyl radicals الباراسيتامول الأسبرين التفكك الضوئي جذور الهيدروكسيل فانتون Index. décimale : 540 Chimie et sciences connexes Résumé : The photodegradation of two pharmaceuticals (PP), paracetamol (PC) and aspirin (ASP), induced by an iron (III) oxyhydroxide (Goethite) was studied in aqueous solution in heterogeneous phase. The phototransformation of the substrates was followed by spectrophotometry and HPLC in various mixtures namely: PP-Goethite, PP-Goethite-H2O2 and PP-Goethite-carboxylic acid. In absence of light both substrates showed different behavior with regard to Goethite in aqueous solution. Indeed, no interaction was observed in the case of the PC whereas a particular reaction was highlighted in the case of the ASP. Under irradiation, photodegradation of PP induced by Goethite shows slow kinetics and is dependent on several parameters such as pH, substrate concentration and catalyst. Fe (II) formed exclusively in the ASP-Goethite mixture shows the photocatalytic dissolution of Goethite. The mechanistic study reveals that hydroxyl radicals are not involved in the photocatalytic process of PC, however they govern on the photodegradation mechanism of ASP. The addition of hydrogen peroxide in the PP-Goethite mixture improves significantly the rate of disappearance of the substrates following a large production of ●OH radicals generated by a heterogeneous photo Fenton reaction. Different parameters have been studied, the effect of pH, as well as the concentration of H2O2.
The addition of carboxylic acid to the PP-Goethite system has also been studied and shows that oxalic acid has the most important photoactivity following the involvement of the eterogeneous like-Fenton process resulting from the photoreductive dissolution of the complex surface formed between Fe (III) of Goethite and oxalic acid. The following of the mineralization shows that the life of intermediates reaction is much greater than the starting product. In order to verify the feasibility of the photochemical process in the environment, the same systems were studied under solar irradiation. The results show that such systems operate with kinetics of the same order as those observed in artificial irradiations. These results provide some knowledge about the fate of PP in the aquatic environment as well as the photocatalytic treatment with oxy (hydroxides) of Fe (III). These results are very promising for the application of this system under pH conditions close to those met in the environment.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/MAM7351.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11001 Comportements thermique et photochimique du paracétamol et de l’aspirine par la goethite en solution aqueuse en phase hétérogène [texte imprimé] / Yazid Mameri, Auteur ; Nadra Debbache, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 177 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Paracétamol Aspirine Photodégradation Radicaux hydroxyle Goethite Fenton Paracetamol Aspirin Photodegradation Hydroxyl radicals الباراسيتامول الأسبرين التفكك الضوئي جذور الهيدروكسيل فانتون Index. décimale : 540 Chimie et sciences connexes Résumé : The photodegradation of two pharmaceuticals (PP), paracetamol (PC) and aspirin (ASP), induced by an iron (III) oxyhydroxide (Goethite) was studied in aqueous solution in heterogeneous phase. The phototransformation of the substrates was followed by spectrophotometry and HPLC in various mixtures namely: PP-Goethite, PP-Goethite-H2O2 and PP-Goethite-carboxylic acid. In absence of light both substrates showed different behavior with regard to Goethite in aqueous solution. Indeed, no interaction was observed in the case of the PC whereas a particular reaction was highlighted in the case of the ASP. Under irradiation, photodegradation of PP induced by Goethite shows slow kinetics and is dependent on several parameters such as pH, substrate concentration and catalyst. Fe (II) formed exclusively in the ASP-Goethite mixture shows the photocatalytic dissolution of Goethite. The mechanistic study reveals that hydroxyl radicals are not involved in the photocatalytic process of PC, however they govern on the photodegradation mechanism of ASP. The addition of hydrogen peroxide in the PP-Goethite mixture improves significantly the rate of disappearance of the substrates following a large production of ●OH radicals generated by a heterogeneous photo Fenton reaction. Different parameters have been studied, the effect of pH, as well as the concentration of H2O2.
The addition of carboxylic acid to the PP-Goethite system has also been studied and shows that oxalic acid has the most important photoactivity following the involvement of the eterogeneous like-Fenton process resulting from the photoreductive dissolution of the complex surface formed between Fe (III) of Goethite and oxalic acid. The following of the mineralization shows that the life of intermediates reaction is much greater than the starting product. In order to verify the feasibility of the photochemical process in the environment, the same systems were studied under solar irradiation. The results show that such systems operate with kinetics of the same order as those observed in artificial irradiations. These results provide some knowledge about the fate of PP in the aquatic environment as well as the photocatalytic treatment with oxy (hydroxides) of Fe (III). These results are very promising for the application of this system under pH conditions close to those met in the environment.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/MAM7351.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11001 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité MAM/7351 MAM/7351 Thèse Bibliothèque principale Thèses Disponible
Titre : Photodegradation des produits pharmaceutiques induite par les complexes organiques de Fer(III) en solution aqueuse. Type de document : texte imprimé Auteurs : Imane Ghoul, Auteur ; Nadra Debbache, Directeur de thèse Mention d'édition : 15-janv-20 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2020 Importance : 226 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 Diclofénac Aspirine Carbamazépine Fe(III)Cit Fenton photolyse Diclofenac Aspirin Photolysis ديكلوفيناك الأسبرين كاربامازيبين التحلل الضوئي Index. décimale : 540 Chimie et sciences connexes Résumé :
This work is a contribution to the photodegradation of three pharmaceutical compounds:
diclofenac (DCF), aspirin (ASP) and carbamazepine (CBZ) induced by organic complex of Fe(III) (Fe(III)Cit) in homogeneous phase under simulated and sunlight. A first part was devoted to the synthesis and characterization of Fe(III)Cit complex, which confirms its stability, its stoichiometry, while the effect of light irradiation revealed its photolysis, which generated the HO• radical. This oxidizing species has shown its effectiveness in the elimination of PP. In the second part of the work, the study of PP-Fe(III)Cit mixtures in aqueous solution was undertaken in the absence and presence of light. Indeed, in the dark, the three substrates showed no interaction with Fe(III)Cit complex in aqueous solution when the mixture ages at room temperature. Under irradiation, the photodegradation of substrates induced by Fe(III)Cit complex, followed by spectrophotometry and HPLC, shows rapid kinetics in the beginning of reaction and then slowed down during the irradiation. This reaction appears to be dependent on several parameters such as pH, substrate and complex concentration. The Fe(II) and the hydrogen peroxide resulting from the photolysis of the complex have been quantified and highlight the involvement of the Fenton reaction in the oxidation process of PP. The mechanistic study reveals that hydroxyl radicals are involved in the photocatalytic process and this whatever the substrate used. The identification of the reaction intermediates by LC-MS made it possible to establish a degradation mechanism for each substrate. The following of the mineralization shows that the life of intermediates reaction is much greater than the starting product. To activate the photocatalytic process, the addition of hydrogen peroxide in the mixture DCFFe(III)Cit improves significantly the rate of disappearance of the substrate. To get closer to the environmental conditions, the effect of main elements present naturally in the aquatic ecosystem such as humic substances, bicarbonates and metals was examined and shows the need to take into account the impact of these elements. In order to verify the feasibility of the photochemical process in the environment, the same systems were studied under solar irradiation. The results show that such systems operate with higher kinetics as those observed in artificial irradiations..
Note de contenu : Annexe. Diplôme : Doctorat En ligne : ../theses/chimie/GHO7668.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11502 Photodegradation des produits pharmaceutiques induite par les complexes organiques de Fer(III) en solution aqueuse. [texte imprimé] / Imane Ghoul, Auteur ; Nadra Debbache, Directeur de thèse . - 15-janv-20 . - جامعة الإخوة منتوري قسنطينة, 2020 . - 226 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Chimie: Chimie Analytique et Environnement Diclofénac Aspirine Carbamazépine Fe(III)Cit Fenton photolyse Diclofenac Aspirin Photolysis ديكلوفيناك الأسبرين كاربامازيبين التحلل الضوئي Index. décimale : 540 Chimie et sciences connexes Résumé :
This work is a contribution to the photodegradation of three pharmaceutical compounds:
diclofenac (DCF), aspirin (ASP) and carbamazepine (CBZ) induced by organic complex of Fe(III) (Fe(III)Cit) in homogeneous phase under simulated and sunlight. A first part was devoted to the synthesis and characterization of Fe(III)Cit complex, which confirms its stability, its stoichiometry, while the effect of light irradiation revealed its photolysis, which generated the HO• radical. This oxidizing species has shown its effectiveness in the elimination of PP. In the second part of the work, the study of PP-Fe(III)Cit mixtures in aqueous solution was undertaken in the absence and presence of light. Indeed, in the dark, the three substrates showed no interaction with Fe(III)Cit complex in aqueous solution when the mixture ages at room temperature. Under irradiation, the photodegradation of substrates induced by Fe(III)Cit complex, followed by spectrophotometry and HPLC, shows rapid kinetics in the beginning of reaction and then slowed down during the irradiation. This reaction appears to be dependent on several parameters such as pH, substrate and complex concentration. The Fe(II) and the hydrogen peroxide resulting from the photolysis of the complex have been quantified and highlight the involvement of the Fenton reaction in the oxidation process of PP. The mechanistic study reveals that hydroxyl radicals are involved in the photocatalytic process and this whatever the substrate used. The identification of the reaction intermediates by LC-MS made it possible to establish a degradation mechanism for each substrate. The following of the mineralization shows that the life of intermediates reaction is much greater than the starting product. To activate the photocatalytic process, the addition of hydrogen peroxide in the mixture DCFFe(III)Cit improves significantly the rate of disappearance of the substrate. To get closer to the environmental conditions, the effect of main elements present naturally in the aquatic ecosystem such as humic substances, bicarbonates and metals was examined and shows the need to take into account the impact of these elements. In order to verify the feasibility of the photochemical process in the environment, the same systems were studied under solar irradiation. The results show that such systems operate with higher kinetics as those observed in artificial irradiations..
Note de contenu : Annexe. Diplôme : Doctorat En ligne : ../theses/chimie/GHO7668.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11502 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité GHO/7668 GHO/7668 Thèse Bibliothèque principale Thèses Disponible
