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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 ????? ?????? ?????? ??????? ??? ??????? 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 : https://bu.umc.edu.dz/md/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 . - [S.l.] : 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 ????? ?????? ?????? ??????? ??? ??????? 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 : https://bu.umc.edu.dz/md/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 : 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 ??? ????? ???? ????? ??? ??????? ????? ????? ??????? ???? ???? ??? ?????????? ?????? ???? ????? ???? ????? ??????? ? ???? ??????? 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 : https://bu.umc.edu.dz/md/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 . - [S.l.] : 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 ??? ????? ???? ????? ??? ??????? ????? ????? ??????? ???? ???? ??? ?????????? ?????? ???? ????? ???? ????? ??????? ? ???? ??????? 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 : https://bu.umc.edu.dz/md/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 ; Université Mentouri, Editeur 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 : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=3754 Photodégradation directe et induite de micro -polluants organiques (cas d'un colorant azoique) [texte imprimé] / Radia Tafer ; Université Mentouri, Editeur 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 : https://bu.umc.edu.dz/md/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 : Elimination d'un polluant organique par photodégradation par des p Type de document : texte imprimé Auteurs : Zakaria Redouane Salah ; Université Mentouri, Editeur scientifique ; M.A. Malouki, Directeur de thèse Année de publication : 2010 Importance : 128 f. Note générale : 01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Colorant Photodégradation Procédés d'oxydation avancés Orange II Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/RED5823.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=3723 Elimination d'un polluant organique par photodégradation par des p [texte imprimé] / Zakaria Redouane Salah ; Université Mentouri, Editeur scientifique ; M.A. Malouki, Directeur de thèse . - 2010 . - 128 f.
01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Colorant Photodégradation Procédés d'oxydation avancés Orange II Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/RED5823.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=3723 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité RED/5823 RED/5823 Thèse Bibliothèque principale Thèses Disponible
Titre : Comportement d’un oxyhydroxyde de Fe(III) vis-à-vis d’un produit pharmaceutique en solution aqueuse en présence de lumières naturelle et simulée. Type de document : texte imprimé Auteurs : Mohamed el Mehdi Benacherine, Auteur ; Nadra Debbache, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 167 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Amoxicilline Photodégradation Radicaux hydroxyle Goethite Fenton Amoxicillin photodegradation hydroxyl radicals hydrogen peroxide oxalic acid ??????????? ?????? ?????? ?????? ????????????? •OH ?????? ???????? (GOE) (like Fenton) ????????? ?????? Index. décimale : 540 Chimie et sciences connexes Résumé : Our objectives in this thesis were to demonstrate the effectiveness of Goethite (GOE) in the
amoxicillin (AMX) photodegradation process under artificial and solar irradiation by different
systems, as well as the optimization of experimental parameters affecting the rate of the
degradation. Different analytical methods have been used in the characterization of AMX and
GOE. In the absence of light, the transformation of AMX was studied in different mixtures
(AMX-GOE, AMX-GOE-H2O2 and AMX-GOE-Carboxylic Acid). An interaction between
AMX and GOE was demonstrated; H2O2 significantly improved the degradation of AMX
while no effect was mentioned in the case of the presence of carboxylic acids. Under
irradiation and in the absence of GOE, AMX was found to be photolysed at 254 nm and
refractory to photolysis at 365 nm (monochromatic and polychromatic); this is due to the
overlap between the absorption spectrum of AMX and the light source.
The photodegradation of AMX by heterogeneous photocatalysis in the presence of GOE has
been studied. Results show that the photodegradation is dependent on several parameters such
as pH, substrate and catalyst concentration. The use of free radical inhibitors has shown that
the reaction mechanism is dominated by •OH radicals where oxygen plays an important role.
The addition of H2O2 to the solution improves the degradation of AMX and increases its rate
of mineralization in terms of chemical oxygen demand. The degradation is effected by the
contribution of the •OH radicals and also by oxidation on the surface of GOE. The AMXGOE-carboxylic acid system has been tested, among the used acids, oxalic acid was the only
one that showed a photo-activity. By comparing the degradation kinetics of AMX in natural
and artificial light in the three studied systems, it is found that the degradation rate is higher
under solar irradiation.
Diplôme : Doctorat En ligne : ../theses/chimie/BEN7137.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10465 Comportement d’un oxyhydroxyde de Fe(III) vis-à-vis d’un produit pharmaceutique en solution aqueuse en présence de lumières naturelle et simulée. [texte imprimé] / Mohamed el Mehdi Benacherine, Auteur ; Nadra Debbache, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2017 . - 167 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Amoxicilline Photodégradation Radicaux hydroxyle Goethite Fenton Amoxicillin photodegradation hydroxyl radicals hydrogen peroxide oxalic acid ??????????? ?????? ?????? ?????? ????????????? •OH ?????? ???????? (GOE) (like Fenton) ????????? ?????? Index. décimale : 540 Chimie et sciences connexes Résumé : Our objectives in this thesis were to demonstrate the effectiveness of Goethite (GOE) in the
amoxicillin (AMX) photodegradation process under artificial and solar irradiation by different
systems, as well as the optimization of experimental parameters affecting the rate of the
degradation. Different analytical methods have been used in the characterization of AMX and
GOE. In the absence of light, the transformation of AMX was studied in different mixtures
(AMX-GOE, AMX-GOE-H2O2 and AMX-GOE-Carboxylic Acid). An interaction between
AMX and GOE was demonstrated; H2O2 significantly improved the degradation of AMX
while no effect was mentioned in the case of the presence of carboxylic acids. Under
irradiation and in the absence of GOE, AMX was found to be photolysed at 254 nm and
refractory to photolysis at 365 nm (monochromatic and polychromatic); this is due to the
overlap between the absorption spectrum of AMX and the light source.
The photodegradation of AMX by heterogeneous photocatalysis in the presence of GOE has
been studied. Results show that the photodegradation is dependent on several parameters such
as pH, substrate and catalyst concentration. The use of free radical inhibitors has shown that
the reaction mechanism is dominated by •OH radicals where oxygen plays an important role.
The addition of H2O2 to the solution improves the degradation of AMX and increases its rate
of mineralization in terms of chemical oxygen demand. The degradation is effected by the
contribution of the •OH radicals and also by oxidation on the surface of GOE. The AMXGOE-carboxylic acid system has been tested, among the used acids, oxalic acid was the only
one that showed a photo-activity. By comparing the degradation kinetics of AMX in natural
and artificial light in the three studied systems, it is found that the degradation rate is higher
under solar irradiation.
Diplôme : Doctorat En ligne : ../theses/chimie/BEN7137.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10465 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/7137 BEN/7137 Thèse Bibliothèque principale Thèses Disponible
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