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Partager le résultat de cette recherche Interroger des sources externesPhotodégradation du chlorure de 1-hexyl-3- methylimidazolium en milieu aqueux homogène et hétérogène. / Ameur Boutiti
Titre : Photodégradation du chlorure de 1-hexyl-3- methylimidazolium en milieu aqueux homogène et hétérogène. Type de document : texte imprimé Auteurs : Ameur Boutiti, Auteur ; Razika Zouaghi, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 123 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Photodégradation Liquide ionique Procédé d’Oxydation Avancée H2O2/UV S2O82–/UV TiO2/UV Photodegradation Ionic liquid Advanced Oxidation Processes الهدم الضوئي السائل الأيوني طرق الأكسدة Index. décimale : 540 Chimie et sciences connexes Résumé : 1-hexyl-3-methylimidazolium chloride (HMImCl) removal from aqueous solution has been achieved by different advanced oxidation processes (AOPs).
HMImCl direct photolysis at 254 nm showed that oxygen mainly intervenes to give O2–·, it can then react with water to form hydrogen peroxide, capable to photolyze and lead to the formation of radicals HO•. On the other hand, singlet oxygen does not participate in the oxidation reaction.
HMImCl degradation rate is appreciably increased by combining the strong oxidant H2O2 with UV light. The H2O2/UV process efficiency is enhanced by increasing H2O2 concentration up to a limit value imposed by self-quenching reactions. High alkalinity favors the disappearance while current inorganic anions chlorides, in acidic medium, inhibit it. Very similar results are obtained with S2O82-/UV process with, in particular, a rate that increases up to a limiting value of the oxidant concentration.
The reaction rate constants of the hydroxyl radicals determined for the two ionic liquids studied, transcribe the high reactivity and the speed of reaction of hydroxyl radicals on ionic liquid. The reaction rate constant of hydroxyl radicals on HMImCl is the same whatever the concentration of HMImCl Heterogeneous photocatalysis on TiO2 proved to be efficient to degrade HMImCl. The process is further improved by H2O2 or S2O82- addition up to an optimum but inhibited by anion chloride in acidic medium. The process is adequately described by the LangmuirHinshelwood kinetic model.
Selective heterogeneous photocatalysis of HMImCl in presence of benzoic acid has demonstrated that benzoic acid affect HMImCl’s degradation. A good selectivity was obtained in acidic medium, where only benzoic acid has been degraded.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/BOU7188.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10750 Photodégradation du chlorure de 1-hexyl-3- methylimidazolium en milieu aqueux homogène et hétérogène. [texte imprimé] / Ameur Boutiti, Auteur ; Razika Zouaghi, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 123 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Photodégradation Liquide ionique Procédé d’Oxydation Avancée H2O2/UV S2O82–/UV TiO2/UV Photodegradation Ionic liquid Advanced Oxidation Processes الهدم الضوئي السائل الأيوني طرق الأكسدة Index. décimale : 540 Chimie et sciences connexes Résumé : 1-hexyl-3-methylimidazolium chloride (HMImCl) removal from aqueous solution has been achieved by different advanced oxidation processes (AOPs).
HMImCl direct photolysis at 254 nm showed that oxygen mainly intervenes to give O2–·, it can then react with water to form hydrogen peroxide, capable to photolyze and lead to the formation of radicals HO•. On the other hand, singlet oxygen does not participate in the oxidation reaction.
HMImCl degradation rate is appreciably increased by combining the strong oxidant H2O2 with UV light. The H2O2/UV process efficiency is enhanced by increasing H2O2 concentration up to a limit value imposed by self-quenching reactions. High alkalinity favors the disappearance while current inorganic anions chlorides, in acidic medium, inhibit it. Very similar results are obtained with S2O82-/UV process with, in particular, a rate that increases up to a limiting value of the oxidant concentration.
The reaction rate constants of the hydroxyl radicals determined for the two ionic liquids studied, transcribe the high reactivity and the speed of reaction of hydroxyl radicals on ionic liquid. The reaction rate constant of hydroxyl radicals on HMImCl is the same whatever the concentration of HMImCl Heterogeneous photocatalysis on TiO2 proved to be efficient to degrade HMImCl. The process is further improved by H2O2 or S2O82- addition up to an optimum but inhibited by anion chloride in acidic medium. The process is adequately described by the LangmuirHinshelwood kinetic model.
Selective heterogeneous photocatalysis of HMImCl in presence of benzoic acid has demonstrated that benzoic acid affect HMImCl’s degradation. A good selectivity was obtained in acidic medium, where only benzoic acid has been degraded.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/BOU7188.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10750 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7188 BOU/7188 Thèse Bibliothèque principale Thèses Disponible
Titre : Photodegradation d’un liquide ionique a base de cation pyridinium en solution aqueuse homogene et heterogene. Type de document : texte imprimé Auteurs : Oualida Nour El Houda Kaabeche, Auteur ; Razika Zouaghi, Auteur Mention d'édition : 24/10/2019 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 196 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 Liquide ionique Photodégradation Procédés d’Oxydation Avancée Radicaux
hydroxyle Photocatalyse Ionic liquid Photodegradation Advanced oxidation processes Hydroxyl radicals Photocatalysis السائل الأيوني التحلل الضوئي عمليات الأكسدة المتقدمة جذور الهيدروكسل التحفيز الضوئيIndex. décimale : 540 Chimie et sciences connexes Résumé : This study focused on the application of photochemical processes (direct photolysis and advanced oxidation processes) in the degradation of an ionic liquid; 1-hexylpyridinium bromide (HPyBr) in aqueous solution. These experiments were conducted in homogeneous phase and in heterogeneous phase. In homogeneous medium, the degradation of HPyBr was studied by different photochemical processes (UV254 nm, UV365 nm, solar irradiation and H2O2/UV254 nm) and by Fenton reagent (Fe2+/H2O2) and photo-Fenton (Fe2+/H2O2 /UV365 nm).
Various physico-chemical parameters have been tested in order to optimize the efficiency of these processes. The comparison of the performances of the various processes studied shows that H2O2/UV254 nm and Fe2+/H2O2/UV365 nm processes are the most efficient. In heterogeneous medium, two metal oxides such as ZnO and TiO2 p25 Degussa were used to compare their photoactivity on the degradation and mineralization of HPyBr. The results obtained show that the percentage of HPyBr adsorption is negligible in the presence of both catalysts. The photocatalytic degradation tests of HPyBr showed that ZnO/UV system was more efficient than the TiO2/UV system, and the disappearance kinetic of HPyBr is correctly described by the Langmuir-Hinshelwood model. The influence of the experimental parameters on the rate of degradation (substrate concentration, catalyst concentrations, pH, the addition of hydrogen peroxide, humic substances, inorganic ions, etc.) was studied. The significant inhibition of the photocatalytic reaction by the addition of chemical scavengers such as isopropanol and triethanolamine confirms that the major pathway for the degradation of HPyBr is due to the hydroxyl •OH radicals formed by irradiation of the photocatalyst surface. The oxidation (COD) and the mineralization (TOC) decrease according to the treatment but more slowly than the degradation, this confirms that the treatment of HPyBr by the photocatalytic process leads to the decrease of the organic matter content, however it requires a relatively slow processing time. In order to verify the feasibility of the photocatalytic process in the environment, both systems were studied under solar irradiation. The results show that the efficiency at this scale is greater than artificial radiation.
Diplôme : Doctorat En ligne : ../theses/chimie/KAA7572.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11410 Photodegradation d’un liquide ionique a base de cation pyridinium en solution aqueuse homogene et heterogene. [texte imprimé] / Oualida Nour El Houda Kaabeche, Auteur ; Razika Zouaghi, Auteur . - 24/10/2019 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 196 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Chimie: Chimie Analytique et Environnement Liquide ionique Photodégradation Procédés d’Oxydation Avancée Radicaux
hydroxyle Photocatalyse Ionic liquid Photodegradation Advanced oxidation processes Hydroxyl radicals Photocatalysis السائل الأيوني التحلل الضوئي عمليات الأكسدة المتقدمة جذور الهيدروكسل التحفيز الضوئيIndex. décimale : 540 Chimie et sciences connexes Résumé : This study focused on the application of photochemical processes (direct photolysis and advanced oxidation processes) in the degradation of an ionic liquid; 1-hexylpyridinium bromide (HPyBr) in aqueous solution. These experiments were conducted in homogeneous phase and in heterogeneous phase. In homogeneous medium, the degradation of HPyBr was studied by different photochemical processes (UV254 nm, UV365 nm, solar irradiation and H2O2/UV254 nm) and by Fenton reagent (Fe2+/H2O2) and photo-Fenton (Fe2+/H2O2 /UV365 nm).
Various physico-chemical parameters have been tested in order to optimize the efficiency of these processes. The comparison of the performances of the various processes studied shows that H2O2/UV254 nm and Fe2+/H2O2/UV365 nm processes are the most efficient. In heterogeneous medium, two metal oxides such as ZnO and TiO2 p25 Degussa were used to compare their photoactivity on the degradation and mineralization of HPyBr. The results obtained show that the percentage of HPyBr adsorption is negligible in the presence of both catalysts. The photocatalytic degradation tests of HPyBr showed that ZnO/UV system was more efficient than the TiO2/UV system, and the disappearance kinetic of HPyBr is correctly described by the Langmuir-Hinshelwood model. The influence of the experimental parameters on the rate of degradation (substrate concentration, catalyst concentrations, pH, the addition of hydrogen peroxide, humic substances, inorganic ions, etc.) was studied. The significant inhibition of the photocatalytic reaction by the addition of chemical scavengers such as isopropanol and triethanolamine confirms that the major pathway for the degradation of HPyBr is due to the hydroxyl •OH radicals formed by irradiation of the photocatalyst surface. The oxidation (COD) and the mineralization (TOC) decrease according to the treatment but more slowly than the degradation, this confirms that the treatment of HPyBr by the photocatalytic process leads to the decrease of the organic matter content, however it requires a relatively slow processing time. In order to verify the feasibility of the photocatalytic process in the environment, both systems were studied under solar irradiation. The results show that the efficiency at this scale is greater than artificial radiation.
Diplôme : Doctorat En ligne : ../theses/chimie/KAA7572.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11410 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KAA/7572 KAA/7572 Thèse Bibliothèque principale Thèses Disponible
Titre : Simulated sunlight photodegradation of an organic pollutant by heterogeneous photo-Fenton-like processes: case of 2-mercaptobenzothiazole using a local natural clay powder. Titre original : Photodégradation d'un polluant organique sous la lumière solaire simulée, par un processus type photo-Fenton hétérogène: cas de photodégradation du 2-mercaptobenzothiazole en présence d’une poudre argileuse naturelle locale. Type de document : texte imprimé Auteurs : Zakaria Redouane Salah, Auteur ; Moulay Abderrahmane Malouki, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 163 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Anglais (eng) Catégories : Français - Anglais
ChimieTags : MBT heterogeneous photo-Fenton process natural clay powder (NCP) photodegradation hydroxyl radical simulated sunlight irradiation procédé photo-Fenton hétérogène poudre d'argile naturelle photodégradation radical hydroxyle irradiation solaire simulée مبت عملیة فوتو فنتون غیر متجانسة مسحوق الطین الطبیعي تحلل ضوئي جذر ھیدروكسیلي محاكاة أشعة الشمس أشعة مافوق بنفسجیة أ آلیة التفاعل Index. décimale : 540 Chimie et sciences connexes Résumé : The problem of water pollution has been an environmental concern for many years, which lead researchers around the world to looking for effective methods to solve this issue. The incapability of conventional methods to remove effectively biorecalcitrant and toxic pollutants, have promoted the research of more efficient and ecologically friendly water treatment technologies.
In the same aspect, this thesis is a small contribution to the development of a new advanced oxidation process considered as promising and clean method for the destruction of water pollutants. In this process we investigated the efficiency of untreated local natural clay rich in iron oxides as a cost-free photocatalyst for the
degradation of a persistent organic pollutant under simulated sunlight irradiation. The targeted pollutant was: 2-mercaptobenzothiazole (MBT). The study showed that:
Firstly, the adsorption capacity, kinetics and isotherms models were examined in thedark.
Secondly, experiments of degradation by heterogeneous Fenton process under variousoperational parameters were investigated.And then, we focused our research on the photodegradation of MBT by heterogeneous photo-Fenton process using the same natural clay powder (NCP) as photocatalyst and under simulated sunlight irradiation. Experiments were conducted at natural pH with a bath reactor equipped with a medium-pressure Hg lamp emitting mainly at 366 nm. The natural clay was crushed into small homogeneous particles (powder) and then characterized by SEM-EDS, UV-Vis diffuse reflectance spectroscopy, XRF and XRD analysis. The specific BET surface area measured for the clay was 30.22 m²·g-1.
Our main results indicated that, the photodegradation of MBT follows first order (for direct photolysis) or pseudo-first order kinetics (for photocatalysis) Direct photolysis of MBT showed a negligible effect both upon 254 and 365 nm irradiation, while 42.5% and 62% of MBT was eliminated in 3 h under 310 nm irradiation in the presence of H2O2, and under sunlight irradiation (using NCP), respectively. Kinetic runs carried out with 5,0.10-5M MBT and 0.5g·L-1clay showed higher MBT conversion and photodegradation rate at basic pH and in oxygenated
media.
The photodegradation of MBT is mainly attributed to reaction with HO, leading to different intermediates that have been identified by HPLC-MS. A reaction mechanism is proposed at the end of our thesis. The highest TOC removals were obtained using UVA at low pHs, in the absence of O2 with 68% and 65% TOC removal respectively.
The presence of oxalic acid and H2O2 enhanced significantly MBT photodegradation.
Finally, the obtained results support the use of natural clay rich in iron oxides as a free, clean and efficient photocatalysts for water pollutants abatement.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/RED7300.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10915 Simulated sunlight photodegradation of an organic pollutant by heterogeneous photo-Fenton-like processes: case of 2-mercaptobenzothiazole using a local natural clay powder. = Photodégradation d'un polluant organique sous la lumière solaire simulée, par un processus type photo-Fenton hétérogène: cas de photodégradation du 2-mercaptobenzothiazole en présence d’une poudre argileuse naturelle locale. [texte imprimé] / Zakaria Redouane Salah, Auteur ; Moulay Abderrahmane Malouki, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 163 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Anglais (eng)
Catégories : Français - Anglais
ChimieTags : MBT heterogeneous photo-Fenton process natural clay powder (NCP) photodegradation hydroxyl radical simulated sunlight irradiation procédé photo-Fenton hétérogène poudre d'argile naturelle photodégradation radical hydroxyle irradiation solaire simulée مبت عملیة فوتو فنتون غیر متجانسة مسحوق الطین الطبیعي تحلل ضوئي جذر ھیدروكسیلي محاكاة أشعة الشمس أشعة مافوق بنفسجیة أ آلیة التفاعل Index. décimale : 540 Chimie et sciences connexes Résumé : The problem of water pollution has been an environmental concern for many years, which lead researchers around the world to looking for effective methods to solve this issue. The incapability of conventional methods to remove effectively biorecalcitrant and toxic pollutants, have promoted the research of more efficient and ecologically friendly water treatment technologies.
In the same aspect, this thesis is a small contribution to the development of a new advanced oxidation process considered as promising and clean method for the destruction of water pollutants. In this process we investigated the efficiency of untreated local natural clay rich in iron oxides as a cost-free photocatalyst for the
degradation of a persistent organic pollutant under simulated sunlight irradiation. The targeted pollutant was: 2-mercaptobenzothiazole (MBT). The study showed that:
Firstly, the adsorption capacity, kinetics and isotherms models were examined in thedark.
Secondly, experiments of degradation by heterogeneous Fenton process under variousoperational parameters were investigated.And then, we focused our research on the photodegradation of MBT by heterogeneous photo-Fenton process using the same natural clay powder (NCP) as photocatalyst and under simulated sunlight irradiation. Experiments were conducted at natural pH with a bath reactor equipped with a medium-pressure Hg lamp emitting mainly at 366 nm. The natural clay was crushed into small homogeneous particles (powder) and then characterized by SEM-EDS, UV-Vis diffuse reflectance spectroscopy, XRF and XRD analysis. The specific BET surface area measured for the clay was 30.22 m²·g-1.
Our main results indicated that, the photodegradation of MBT follows first order (for direct photolysis) or pseudo-first order kinetics (for photocatalysis) Direct photolysis of MBT showed a negligible effect both upon 254 and 365 nm irradiation, while 42.5% and 62% of MBT was eliminated in 3 h under 310 nm irradiation in the presence of H2O2, and under sunlight irradiation (using NCP), respectively. Kinetic runs carried out with 5,0.10-5M MBT and 0.5g·L-1clay showed higher MBT conversion and photodegradation rate at basic pH and in oxygenated
media.
The photodegradation of MBT is mainly attributed to reaction with HO, leading to different intermediates that have been identified by HPLC-MS. A reaction mechanism is proposed at the end of our thesis. The highest TOC removals were obtained using UVA at low pHs, in the absence of O2 with 68% and 65% TOC removal respectively.
The presence of oxalic acid and H2O2 enhanced significantly MBT photodegradation.
Finally, the obtained results support the use of natural clay rich in iron oxides as a free, clean and efficient photocatalysts for water pollutants abatement.
Diplôme : Doctorat en sciences En ligne : ../theses/chimie/RED7300.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10915 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité RED/7300 RED/7300 Thèse Bibliothèque principale Thèses Disponible
Titre : Photodégradation directe et induite de micro -polluants organiques (cas d'un colorant azoique) Type de document : texte imprimé Auteurs : Radia Tafer ; Univ. de Constantine, Éditeur scientifique ; A. BOULKAMH, Directeur de thèse Année de publication : 2007 Importance : 119 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Photodégradation Photocatalyse fenton Décoloratuion Noir eriochrome T Procédé d'oxydatioin avancée Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/TAF4795.pdf Permalink : index.php?lvl=notice_display&id=3754 Photodégradation directe et induite de micro -polluants organiques (cas d'un colorant azoique) [texte imprimé] / Radia Tafer ; Univ. de Constantine, Éditeur scientifique ; A. BOULKAMH, Directeur de thèse . - 2007 . - 119 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Photodégradation Photocatalyse fenton Décoloratuion Noir eriochrome T Procédé d'oxydatioin avancée Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/TAF4795.pdf Permalink : index.php?lvl=notice_display&id=3754 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité TAF/4795 TAF/4795 Thèse Bibliothèque principale Thèses Disponible
Titre : Photodegradation du naproxene induite par un Oxyde de Fer (III) (Goethite) sous forme particulaire et nanoparticulaire. Type de document : texte imprimé Auteurs : Nessrine Setifi, Auteur ; Nadra Debbache, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 196 f. Format : 30 cm. Note générale : Doctorat 3éme CYCLE LMD.
2 copies imprimées disponiblesLangues : Français (fre) Catégories : Français - Anglais
ChimieTags : Chimie: Chimie Analytique et Environnement Naproxène Photodégradation Nanoparticule Nanocomposite Goethite Fenton نابروكسين التحلل الضوئي جسيمات متناهية الصغر بمركب متناهي في الصغر الجيوثايت فنتون Index. décimale : 540 Chimie et sciences connexes Résumé :
The photodegradation under artificial and solar irradiation of Naproxen (NPX, induced by 3 iron (III) oxy (hydroxide) based semiconductors (Goethite) was studied in aqueous solution in heterogeneous phase. The phototransformation of the substrate was followed by spectrophotometry and HPLC in the different systems. Semiconductors including particulate Goethite (GO), nanoparticle (nGO) and nanocomposite montmorillonite - Goethite (MGO) were synthesized at laboratory, and characterized by different methods (RDX, BET, SEM, TEM ...). The results of the XRD show good crystallinity. In addition, SEM and TEM analysis revealed that the particle sizes of GO, nGO and MGO are: 5 μm, 37.64 nm and 45.79 nm respectively. The removal of NPX in the presence of GO, in the absence and in the presence of light, has shown that the NPX is eliminated by both processes with a faster rate in the presence of light and seems closely dependent on the PH. The optimization of important parameters in the photochemical process was also undertaken in order to quantify the reagents necessary for the completion of the reaction. The addition of activators such as hydrogen peroxide and oxalic acid in the NPX-GO mixture significantly improves the disappearance of the substrate. In a second part, the degradation of NPX by nGO was undertaken in a similar way comparing with GO. It appeared in the systems nGO-H2O2-UV and nGO- AOx-UV are more efficient than the corresponding simple system. Finally, the performance of the new MGO catalyst has been demonstrated in the degradation of NPX. In the absence of light, an interaction between NPX and MGO was found where 33% of NPX was eliminated for a quantity of MGO of 1 g / L. Under light irradiation, 96.5% of NPX was degraded after 5 hours. The Fe (II) formed exclusively in the mixture shows the photocatalytic dissolution of the MGO. The influence of some parameters has been treated. The degradation efficiency of NPX in mixture (NPX-MGO- H2O2, pH = 3) made it possible to improve the rate of degradation to 100% NPX in 60 minutes. The formation of iron (II) in the H2O2- containing mixture creates the Fenton process under these conditions. The hydroxyl radicals have been demonstrated by the use of 1% isopropanol. Illumination of this mixture significantly advanced the reaction with 100% substrate degradation in only 10 minutes. Several parameters affecting this process have been optimized: pH, MGO dosage and H2O2 concentration. Under solar irradiation, the results showed that 30 minutes were sufficient for complete degradation of NPX at free pH. The effect of pH and some cationic metals allows considering this low-cost process in the elimination of this kind of emerging pollutants.Diplôme : Doctorat En ligne : ../theses/chimie/SET7532.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11371 Photodegradation du naproxene induite par un Oxyde de Fer (III) (Goethite) sous forme particulaire et nanoparticulaire. [texte imprimé] / Nessrine Setifi, Auteur ; Nadra Debbache, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 196 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Chimie: Chimie Analytique et Environnement Naproxène Photodégradation Nanoparticule Nanocomposite Goethite Fenton نابروكسين التحلل الضوئي جسيمات متناهية الصغر بمركب متناهي في الصغر الجيوثايت فنتون Index. décimale : 540 Chimie et sciences connexes Résumé :
The photodegradation under artificial and solar irradiation of Naproxen (NPX, induced by 3 iron (III) oxy (hydroxide) based semiconductors (Goethite) was studied in aqueous solution in heterogeneous phase. The phototransformation of the substrate was followed by spectrophotometry and HPLC in the different systems. Semiconductors including particulate Goethite (GO), nanoparticle (nGO) and nanocomposite montmorillonite - Goethite (MGO) were synthesized at laboratory, and characterized by different methods (RDX, BET, SEM, TEM ...). The results of the XRD show good crystallinity. In addition, SEM and TEM analysis revealed that the particle sizes of GO, nGO and MGO are: 5 μm, 37.64 nm and 45.79 nm respectively. The removal of NPX in the presence of GO, in the absence and in the presence of light, has shown that the NPX is eliminated by both processes with a faster rate in the presence of light and seems closely dependent on the PH. The optimization of important parameters in the photochemical process was also undertaken in order to quantify the reagents necessary for the completion of the reaction. The addition of activators such as hydrogen peroxide and oxalic acid in the NPX-GO mixture significantly improves the disappearance of the substrate. In a second part, the degradation of NPX by nGO was undertaken in a similar way comparing with GO. It appeared in the systems nGO-H2O2-UV and nGO- AOx-UV are more efficient than the corresponding simple system. Finally, the performance of the new MGO catalyst has been demonstrated in the degradation of NPX. In the absence of light, an interaction between NPX and MGO was found where 33% of NPX was eliminated for a quantity of MGO of 1 g / L. Under light irradiation, 96.5% of NPX was degraded after 5 hours. The Fe (II) formed exclusively in the mixture shows the photocatalytic dissolution of the MGO. The influence of some parameters has been treated. The degradation efficiency of NPX in mixture (NPX-MGO- H2O2, pH = 3) made it possible to improve the rate of degradation to 100% NPX in 60 minutes. The formation of iron (II) in the H2O2- containing mixture creates the Fenton process under these conditions. The hydroxyl radicals have been demonstrated by the use of 1% isopropanol. Illumination of this mixture significantly advanced the reaction with 100% substrate degradation in only 10 minutes. Several parameters affecting this process have been optimized: pH, MGO dosage and H2O2 concentration. Under solar irradiation, the results showed that 30 minutes were sufficient for complete degradation of NPX at free pH. The effect of pH and some cationic metals allows considering this low-cost process in the elimination of this kind of emerging pollutants.Diplôme : Doctorat En ligne : ../theses/chimie/SET7532.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11371 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité SET/7532 SET/7532 Thèse Bibliothèque principale Thèses Disponible Permalink
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