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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Framtagande av ett litet och kompakt jonbytarsystem / Development of a small and compact ion exchange system

Lindeberg, Carl, Mumic, Armin January 2022 (has links)
This development project has been carried out in collaboration with the company Hitachi Energy Sweden AB in Landskrona. Hitachi currently uses three different types of ion exchange systems, one of which is compact and is used in smaller cooling systems. Hitachi thinks that their current compact ion exchange system is too expensive and wants to find a cheaper solution, which is why the new compact ion exchange system has been developed. The development of the new compact ion exchange system has resulted in drawings and CAD models of all components, material selection and calculations to validate that the system meets the technical requirements. The new compact ion exchange system has been designed with a view to reducing the cost of manufacturing and materials, as well as assembly and service friendliness. The purpose and goal of the project was achieved.
2

Sorption of metal complex dyes onto ion exchanger resins / Metalo kompleksinių dažiklių sorbcija jonitais

Kazlauskienė, Eglė 31 January 2012 (has links)
Metal complex dyes are a problematic group of substances, present in the negatively charged anion form in mixed industrial wastewater that should be removed. Therefore, a complete removal of these hazardous dyes from wastewaters is necessary to prevent them from release into the environment. Adsorption on activated carbon of dyes has been investigated widely. However some disadvantages using activated carbon in practice were observed, e.g. high regeneration costs and production of fines due to the brittle nature. Since their adsorption capacities, mechanical strength, and other properties need further improvement for wider application, the polymeric sorbents are still under development as a potential alternative to activated carbons. The main aim of the present work was to investigate absorption regularity metal complex Lanasyl Navy M-DNL and Acid Blue 249 (copper (II) phthalocyanine) dyes on synthetic ion exchangers under static conditions and evaluate facility of ion exchangers to removal dyes from wastewaters by dynamic conditions. Screening with chromium-complex dye (acid brown NKM, Lanasyn Navy M-DNL) solutions wide range sorbents, according to the physical chemical characteristics of sorbents and established dye removal parameters (sorption capacity, distribution coefficient and sorbent regeneration) has shown that the polyacrylic, gel type, weakly basic anion exchanger Purolite A 847 (A 845); polystyrene, macroporous, strongly basic anion exchanger Purolite A 500 PS... [to full text] / Pagrindinis aplinkosauginės politikos bruožas yra taršos metalo dažikliais mažinimas gamybos metu ir efektyvių šalinimo iš nuotekų metodų paieška. Regeneruojami, mechaniškai atsparūs ir nekenksmingi gamtai polimeriniai sorbentai naudojami dažikliams valyti yra pranašesni už plačiai paplitusias aktyvintąsias anglis. Ištyrus polimerinių sorbentų sorbcines ir regeneracines savybes, nustačius palankias darbines sąlygas, sorbentai gali būti pritaikomi nuotekų valymui, o išvalytas vanduo grąžinamas atgal į gamybinius procesus. Tokiu būdu, vandens ištekliai gali būti apsaugoti nuo taršos sunkiaisiais metalais ir organiniais junginiais, sumažinti gamybos kaštai, nes regeneruoti sorbentai naudojami pakartotinai. Šiame darbe tiriama metalo kompleksinių dažiklių Navy M-DNL (1:2 chromo monoazo kompleksas) (Navy) ir Acid Blue 249 (Vario (II) ftalocianino tetrasulforūgšties tetranatrio druska) (CuPc) sorbcijos sintetiniais jonitais dėsningumus statinėmis sąlygomis ir įvertinti jonitų galimybes valyti nuotekas nuo dažiklių dinaminėmis sąlygomis. Geriausiai iš vandeninių tirpalų šalinantys dažiklius sorbentai atrinkti pagal geriausią sorbcinė gebą ir regeneraciją, dažiklio pasiskirstymo tirpale koeficientą yra: silpnai baziniai anijonitai Purolite A 847 (A 845), stipriai bazinis anijonitas Purolite A 500PS, nejoninis makrotinklinis sorbentas Macronet MN 200. Statinėmis sąlygomis nustatyta dažiklių (Navy ir CuPc) sorbcijai palankiausia terpė (pH 2) ir temperatūra atitinkamai dažikliui Navy... [toliau žr. visą tekstą]
3

Metalo kompleksinių dažiklių sorbcija jonitais / Sorption of metal complex dyes onto ion exchanger resins

Kazlauskienė, Eglė 31 January 2012 (has links)
Pagrindinis aplinkosauginės politikos bruožas yra taršos metalo dažikliais mažinimas gamybos metu ir efektyvių šalinimo iš nuotekų metodų paieška. Regeneruojami, mechaniškai atsparūs ir nekenksmingi gamtai polimeriniai sorbentai naudojami dažikliams valyti yra pranašesni už plačiai paplitusias aktyvintąsias anglis. Ištyrus polimerinių sorbentų sorbcines ir regeneracines savybes, nustačius palankias darbines sąlygas, sorbentai gali būti pritaikomi nuotekų valymui, o išvalytas vanduo grąžinamas atgal į gamybinius procesus. Tokiu būdu, vandens ištekliai gali būti apsaugoti nuo taršos sunkiaisiais metalais ir organiniais junginiais, sumažinti gamybos kaštai, nes regeneruoti sorbentai naudojami pakartotinai. Šiame darbe tiriama metalo kompleksinių dažiklių Navy M-DNL (1:2 chromo monoazo kompleksas) (Navy) ir Acid Blue 249 (Vario (II) ftalocianino tetrasulforūgšties tetranatrio druska) (CuPc) sorbcijos sintetiniais jonitais dėsningumus statinėmis sąlygomis ir įvertinti jonitų galimybes valyti nuotekas nuo dažiklių dinaminėmis sąlygomis. Geriausiai iš vandeninių tirpalų šalinantys dažiklius sorbentai atrinkti pagal geriausią sorbcinė gebą ir regeneraciją, dažiklio pasiskirstymo tirpale koeficientą yra: silpnai baziniai anijonitai Purolite A 847 (A 845), stipriai bazinis anijonitas Purolite A 500PS, nejoninis makrotinklinis sorbentas Macronet MN 200. Statinėmis sąlygomis nustatyta dažiklių (Navy ir CuPc) sorbcijai palankiausia terpė (pH 2) ir temperatūra atitinkamai dažikliui Navy... [toliau žr. visą tekstą] / Metal complex dyes are a problematic group of substances, present in the negatively charged anion form in mixed industrial wastewater that should be removed. Therefore, a complete removal of these hazardous dyes from wastewaters is necessary to prevent them from release into the environment. Adsorption on activated carbon of dyes has been investigated widely. However some disadvantages using activated carbon in practice were observed, e.g. high regeneration costs and production of fines due to the brittle nature. Since their adsorption capacities, mechanical strength, and other properties need further improvement for wider application, the polymeric sorbents are still under development as a potential alternative to activated carbons. The main aim of the present work was to investigate absorption regularity metal complex Lanasyl Navy M-DNL and Acid Blue 249 (copper (II) phthalocyanine) dyes on synthetic ion exchangers under static conditions and evaluate facility of ion exchangers to removal dyes from wastewaters by dynamic conditions. Screening with chromium-complex dye (acid brown NKM, Lanasyn Navy M-DNL) solutions wide range sorbents, according to the physical chemical characteristics of sorbents and established dye removal parameters (sorption capacity, distribution coefficient and sorbent regeneration) has shown that the polyacrylic, gel type, weakly basic anion exchanger Purolite A 847 (A 845); polystyrene, macroporous, strongly basic anion exchanger Purolite A 500 PS... [to full text]
4

Estudo da região promotora do gene do permutador Na+/H+ (NHE3). / Study of the Na+/H+ (NHE3) exchanger gene promoter region.

Neri, Elida Adalgisa 29 April 2009 (has links)
Tendo em vista a importância do permutador Na+/H+ (isoforma 3) na reabsorção de NaCl e NaHCO3 em túbulos proximais e conseqüentemente no equilíbrio ácido-base e volume celular, surgiu o interesse em identificar a região promotora essencial para a transcrição do gene NHE3 e os elementos de ligação de fatores de transcrição presentes no mesmo, em células de túbulos proximais renais. Para isso, os segmentos da região flanqueadora 5´ do gene NHE3 de rato foram obtidos por PCR e inseridos no plasmídeo pGL3-basic, que codifica o gene repórter Firefly lucíferase. Os seguintes fragmentos foram analisados 1) -157 a +31; 2) -152 a +55; 3) -85 a +31; 4) -65 a +31; 5) -44 a +31; 6) -33 a +31; 7) -25 a +31; 8) -157 a +35, com deleção do elemento GATA (posição +20 a +23). Estes foram transfectados em células OKP, uma linhagem de túbulos proximais de rim de opossum. A atividade promotora de transcrição de cada segmento foi analisada em comparação com a atividade de luciferase observada com a transfecção do vetor pGL3-basic não recombinante, sem promotor. Foi realizado a cotransfecção do vetor pRL-CMV, que contém o gene da proteína repórter Renilla luciferase, usado como controle da eficiência de transfecção. Após serem analisados os resultados, observou-se que a atividade do promotor foi mais elevada com o constructo -152 a +55 (76.52 ± 45.26 (n=9)). Além disso, conseguimos identificar a existência de possíveis ativadores transcricionais no segmento entre a posição 85 e 65 (Egr-1/Sp1); 44 e 33 (Egr-1) e -33 e -25 (elemento TATA-Box não canônico), pois a remoção destes nucleotídeos reduziu significativamente a atividade do promotor. Outra observação foi a presença de elementos inibitórios entre as bases 65 e 44 (Sp1/Ap2), pois com a retirada destes, observamos um aumento muito significativo da atividade do promotor. O menor segmento (25/+31) apresentou atividade promotora significativa, sugerindo que ainda tenha os elementos indispensáveis para a montagem do complexo transcricional primário, embora com eficiência já bem reduzida. A presença do elemento GATA no primeiro exon, embora importante para a transcrição do gene NHE3 em células intestinais, não parece ser importante para a atividade transcricional em células de túbulos proximais. / In view of the importance of the exchanger Na+/H+ (isoform 3), in reabsoption of NaCl and NaHCO3 in proximal tubules and consequently the acid-base balance, and cell volume, came the interest in identifying the region promoter essential for transcription of the NHE3 gene and the elements of the binding of transcription factors present in the same, in cells renal proximal tubules. For this, segments of the 5 flanking region of the rat NHE3 gene were obtained by PCR and inserted into pGL3-basic vector, which encodes Firefly luciferase reporter gene. The following fragments were analyzed 1) -157 to +31, 2) -152 to +55, 3) -85 to +31, 4) -65 to +31, 5) -44 to +31, 6) -33 to +31, 7) -25 to +31; 8) -157 to +35, with deletion of the GATA element (position +20 to +23). These were transfected in OKP cells, line of the renal proximal tubules of opossum kidney. The promoter activity of transcription of each segment was analyzed in comparison with the luciferase activity observed with transfection of the pGL3-basic vector recombinant, without promoter. Was performed cotransfecção of PRL-CMV vector, containing the gene of the reporter protein Renilla luciferase, used as internal control of the efficiency of transfection. After analyzing the results, observed promoter activity was higher with the construct -152 to +55 (76.52 ± 45.26 (n = 9)). Furthermore, we identify the possible existence of transcriptional activators in the segment between position -85 and -65 (Egr-1/Sp1), -44 and -33 (EGR-1) and -33 and -25 (atypical TATA-box element) because the removal of these nucleotides significantly reduced the activity of the promoter. Another observation was the presence of inhibitory elements between bases -65 and -44 (Sp1/Ap2), because with the deletion of these, we observed a very significant increase in the activity of the promoter. The lower segment (-25 / +31) showed significant promoter activity, suggesting that still has the elements essential for transcriptiption complex assembly of the primary, in spite of with reduced efficiency well. The presence of the GATA element in the first exon, although important for the transcription of the NHE3 gene in intestinal cells, does not appear to be important for transcriptional activity in cells of proximal tubules.
5

Chromo kompleksinių dažiklių sorbcija jonitais ir aktyvintosiomis anglimis / Sorption of chromium complex dyes onto ion exchangers and activated carbons

Kirkutė, Jolita 24 September 2008 (has links)
Chromo kompleksinių dažiklių: rūgštinio rudojo (1:1 ir 1:2 chromo kompleksai) ir rūgštinio mėlynojo (1:2 chromo kompleksas) sorbcija aktyvintąja anglimi, neutraliu sorbentu, anijonitu bei chelatiniu jonitu atlikta statinėmis sąlygomis, keičiant pradinio tirpalo koncentracijas, pH, temperatūrą bei sorbcijos trukmę. Pusiausvirosios sorbcijos eksperimentinės vertės ir apskaičiuoti Langmiuro ir Froindlicho teorinių sorbcijos izotermų paramertrų didžiausios vertės liudija, kad sorbcijai palankiausia tirpalo rūgšti terpė. Gautos sorbcijos kinetinės kreivės ir ištirtos pagal tris kinetikos modelius: pseudo-pirmojo laipsnio reakcijos greičio lygtį, pseudo-antrojo laipsnio reakcijos greičio lygtį ir vidinės difuzijos modelį. Nustatyta, kad sorbcijos kinetika vyksta pagal pseudo-antrojo laipsnio reakcijos lygtį ir yra kontroliuojama vidinės difuzijos procesų. Nustatyti sorbcijos proceso termodinaminiai parametrai H0, S0 ir G0 liudija apie spontanišką, egzoterminę sorbcijos aktyvintąja anglimi, anijonitu bei chelatiniu jonitu prigimtį. / Sorption of two chromium complex dyes (1:1 and 1:2 chromium complex; 1:2 chromium comlex) and from model solutions onto an various types of sorbents was investigated in aqueous solution in a batch experiments with respect to initial solution concentration and pH, contact time, and temperature. The sorption capacity at equilibrium obtained experimental and estimated Langmuir and Freundlich isotherm parameters was demonstrate that acidic media was favourable for dye sorption. The pseudo-first-order, pseudo - second order kinetics models and the diffusion (intraparticle) model were used to describe the kinetics data, and the rate constants were evaluated. Kinetics of dye sorption is observed to confirm pseudo-second order rate expression. The activation energy, change of Gibbs free energy, enthalpy of sorption was also evaluated. The results indicate the sorption process onto activated carbon, anion exchanger and chelating sorbent was egzothermic, spontaneous.
6

Estudo da região promotora do gene do permutador Na+/H+ (NHE3). / Study of the Na+/H+ (NHE3) exchanger gene promoter region.

Elida Adalgisa Neri 29 April 2009 (has links)
Tendo em vista a importância do permutador Na+/H+ (isoforma 3) na reabsorção de NaCl e NaHCO3 em túbulos proximais e conseqüentemente no equilíbrio ácido-base e volume celular, surgiu o interesse em identificar a região promotora essencial para a transcrição do gene NHE3 e os elementos de ligação de fatores de transcrição presentes no mesmo, em células de túbulos proximais renais. Para isso, os segmentos da região flanqueadora 5´ do gene NHE3 de rato foram obtidos por PCR e inseridos no plasmídeo pGL3-basic, que codifica o gene repórter Firefly lucíferase. Os seguintes fragmentos foram analisados 1) -157 a +31; 2) -152 a +55; 3) -85 a +31; 4) -65 a +31; 5) -44 a +31; 6) -33 a +31; 7) -25 a +31; 8) -157 a +35, com deleção do elemento GATA (posição +20 a +23). Estes foram transfectados em células OKP, uma linhagem de túbulos proximais de rim de opossum. A atividade promotora de transcrição de cada segmento foi analisada em comparação com a atividade de luciferase observada com a transfecção do vetor pGL3-basic não recombinante, sem promotor. Foi realizado a cotransfecção do vetor pRL-CMV, que contém o gene da proteína repórter Renilla luciferase, usado como controle da eficiência de transfecção. Após serem analisados os resultados, observou-se que a atividade do promotor foi mais elevada com o constructo -152 a +55 (76.52 ± 45.26 (n=9)). Além disso, conseguimos identificar a existência de possíveis ativadores transcricionais no segmento entre a posição 85 e 65 (Egr-1/Sp1); 44 e 33 (Egr-1) e -33 e -25 (elemento TATA-Box não canônico), pois a remoção destes nucleotídeos reduziu significativamente a atividade do promotor. Outra observação foi a presença de elementos inibitórios entre as bases 65 e 44 (Sp1/Ap2), pois com a retirada destes, observamos um aumento muito significativo da atividade do promotor. O menor segmento (25/+31) apresentou atividade promotora significativa, sugerindo que ainda tenha os elementos indispensáveis para a montagem do complexo transcricional primário, embora com eficiência já bem reduzida. A presença do elemento GATA no primeiro exon, embora importante para a transcrição do gene NHE3 em células intestinais, não parece ser importante para a atividade transcricional em células de túbulos proximais. / In view of the importance of the exchanger Na+/H+ (isoform 3), in reabsoption of NaCl and NaHCO3 in proximal tubules and consequently the acid-base balance, and cell volume, came the interest in identifying the region promoter essential for transcription of the NHE3 gene and the elements of the binding of transcription factors present in the same, in cells renal proximal tubules. For this, segments of the 5 flanking region of the rat NHE3 gene were obtained by PCR and inserted into pGL3-basic vector, which encodes Firefly luciferase reporter gene. The following fragments were analyzed 1) -157 to +31, 2) -152 to +55, 3) -85 to +31, 4) -65 to +31, 5) -44 to +31, 6) -33 to +31, 7) -25 to +31; 8) -157 to +35, with deletion of the GATA element (position +20 to +23). These were transfected in OKP cells, line of the renal proximal tubules of opossum kidney. The promoter activity of transcription of each segment was analyzed in comparison with the luciferase activity observed with transfection of the pGL3-basic vector recombinant, without promoter. Was performed cotransfecção of PRL-CMV vector, containing the gene of the reporter protein Renilla luciferase, used as internal control of the efficiency of transfection. After analyzing the results, observed promoter activity was higher with the construct -152 to +55 (76.52 ± 45.26 (n = 9)). Furthermore, we identify the possible existence of transcriptional activators in the segment between position -85 and -65 (Egr-1/Sp1), -44 and -33 (EGR-1) and -33 and -25 (atypical TATA-box element) because the removal of these nucleotides significantly reduced the activity of the promoter. Another observation was the presence of inhibitory elements between bases -65 and -44 (Sp1/Ap2), because with the deletion of these, we observed a very significant increase in the activity of the promoter. The lower segment (-25 / +31) showed significant promoter activity, suggesting that still has the elements essential for transcriptiption complex assembly of the primary, in spite of with reduced efficiency well. The presence of the GATA element in the first exon, although important for the transcription of the NHE3 gene in intestinal cells, does not appear to be important for transcriptional activity in cells of proximal tubules.
7

Propriétés physico-chimiques et modélisation du fonctionnement en colonne d'adsorbants minéraux sélectifs du Cs / Cs-selective mineral adsorbents in columns : physico-chemical properties and modeling

Michel, Caroline 09 December 2015 (has links)
Suite à la catastrophe nucléaire de Fukushima Dai-Ichi, des milliers de tonnes d’eau douce et d’eau de mer ont été utilisées pour le refroidissement des réacteurs ou contaminées du fait des infiltrations souterraines. La décontamination de ces eaux est rendue difficile par la présence d’autres cations (Na+, K+, Ca2+, Mg2+) présents naturellement dans ces eaux. Un procédé de décontamination en colonne garnie de deux types adsorbants minéraux, le TERMOXID 35 et le SORBMATECH® 202, a été étudié dans ce contexte. Le premier est un adsorbant commercial constitué du ferrocyanure mixte K/Ni imprégnés sur une matrice solide Zr(OH)4. Le second, synthétisé au CEA, est composé de ferrocyanure K/Cu imprégnés sur une matrice solide SiO2. Ces deux matériaux se sont révélés extrêmement efficaces pour décontaminer le Cs dans l’eau de mer avec des Kd,Cs de l’ordre de 105 mL/g.Les études menées en batch dans différentes solutions (eau pure, eau douce et eau de mer) ont permis de mettre en évidence les cinétiques de sorption ainsi que les mécanismes d’échange d’ions responsables de la sorption du Cs+ en tenant compte des effets compétitifs des cations des eaux naturelles. La modélisation des batchs a été menée avec le code géochimique CHESS en prenant en compte ces effets compétitifs selon le formalisme de Vanselow et les coefficients de sélectivité en constituant une base de données thermodynamiques spécifique. Les performances de ces matériaux ont ensuite été testées en colonne. Les paramètres opératoires tels que la vitesse de Darcy et le ratio H/D ont été étudiés pour définir les conditions de bon fonctionnement de ce procédé. Le T35 s’est révélé être moins performant du fait notamment de la diffusion lente du Cs dans les pores de ce matériau. Le S202 s’est révélé être un bon candidat pour l’application de forts débits de traitement. Les courbes de percée ainsi obtenues dans l’eau douce ont par ailleurs fait l’objet de modélisation avec les codes de transport réactif HYTEC et OPTIPUR couplés à la base CHESS de données thermodynamiques. Cette démarche permettra de mieux dimensionner les unités de décontamination définies par l’exploitant. / Following the nuclear disaster in Fukushima Dai-Ichi, thousands of tons of fresh water and seawater were used for cooling the reactors or contaminated as a result of groundwater seepage. Decontamination of these waters is complicated by the presence of other cations (Na+, K+, Ca2+, Mg2+) naturally present in these waters. Decontamination process in columns packed was studied in this context with two types of mineral adsorbents: the TERMOXID 35 and the SORBMATECH® 202. The first one is a commercial adsorbent and consists of mixed ferrocyanide K/Ni impregnated over a solid matrix Zr(OH)4. The second one was synthesized in CEA and is composed of ferrocyanide K/Cu impregnated over a solid matrix SiO2. Both materials have shown a high efficiency for Cs decontamination in seawater with Kd,Cs of about 105 mL/g.Batch studies conducted in different solutions (pure water, fresh water and seawater) allowed determining sorption kinetics and ion exchange mechanisms responsible for the sorption of Cs+, taking into account competitive effects of the natural water cations (Na+, K+, Ca2+, Mg2+). Modelling of batchs was performed with the geochemical code CHESS considering competitive effects according to the Vanselow formalism and selectivity coefficients, developing a specific thermodynamic database. The performances of these materials were then tested in column. The operating parameters such as Darcy’s velocity and the H/D ratio were studied for a proper functioning of this process. The T35 has proven to be less efficient mainly because of the slow diffusion of Cs in the pores of the material. The S202 has proven to be a good candidate for the application of high flow rates. The breakthrough curves obtained in fresh water have been modelled with the reactive transport codes HYTEC and OPTIPUR using the CHESS thermodynamic database. This approach will eventually help to support the design of a decontamination unit by the operator.
8

Interactions dans un système césium, strontium/matière organique naturelle/argiles des sols / Interaction between cesium, strontium, natural organic matter and clay minerals

Siroux, Brice 07 November 2017 (has links)
Le projet de thèse s’inscrit dans le Projet Investissement d’Avenir (PIA) DEMETERRES, dont l’objectif est le développement de méthodes et de technologies pour la décontamination et la remédiation des sols et effluents contaminés après un accident nucléaire. L’objectif de cette thèse est de mieux appréhender les interactions de 137Cs et 90Sr avec les différentes composantes des terres agricoles et ainsi être capable de prédire l’état chimique dans lequel ces éléments se trouveraient dans les sols en cas d’accident nucléaire. Une base de données dans le formalisme des échangeurs d’ions multi-sites a été mise en place, représentant les comportements d’adsorption de Cs+ et Sr2+ dans les illites et smectites (deux des principaux minéraux argileux) vis-à-vis des cations majeurs environnementaux H+, Na+ et Ca2+. Cette base de données a par la suite été utilisée pour tenter de prédire le comportement d’adsorption de Cs+ et Sr2+ dans des échantillons de sols agricoles français (Pusignan, Etoile-sur-Rhône et Herqueville). De bonnes simulations du comportement d’adsorption de Cs+ et Sr2+ ont été obtenues sur Pusignan et Etoile-sur-Rhône. Dans le cas d’Herqueville, la suppression de la MON n’a pas amélioré l’accord entre les simulations et les expériences, tandis que l’élimination de l’aluminium échangeable a lui permis une meilleure simulation de l’adsorption de Sr2+, mais pas de Cs+. Ces travaux permettent de simuler efficacement le comportement d’adsorption de Cs et Sr dans des sols et ainsi d’appuyer les stratégies de décontamination et remédiation après un accident nucléaire / This study is part of the DEMETERRES project, which aims to develop new methods and technologies in the field of decontamination and remediation of contaminated soils and effluents after a nuclear accident. The objective of this PhD is to obtain a better knowledge of 137Cs and 90Sr interactions onto agricultural soils and to better predict the chemical state of these elements in soils after a nuclear accident. A database in the multi-sites ion exchanger formalism has been built, reflecting the adsorption behaviours of Cs+ and Sr2+ onto illite and smectite (two major clay minerals) with regards to major environmental cations: i.e. H+, Na+, and Ca2+. It was used to predict the adsorption of Cs+ and Sr2+ onto French agricultural soil samples (Pusignan, Etoile-sur-Rhône and Herqueville). Good simulations of the adsorption of Cs+ and Sr2+ onto Pusignan and Etoile-sur-Rhône are obtained. In the case of Herqueville, the removal of NOM does not improve the agreement between experimental results and simulations, but the removal of exchangeable aluminum allows a better representation of the adsorption results of Sr2+ onto Herqueville, but not for Cs+. This work allows efficiently simulating the adsorption of Cs and Sr onto soils and support decontamination and remediation strategies after a nuclear accident
9

Preparação e propriedades de novos polimeros anion-trocadores cloreto de n-Propil (metilpiridinio) silsesquioxano / Preparation and properties of the new anion-exchanger n-propyl (methylpyridinium) silsesquioxane chloride polymers

Magosso, Herica Aparecida 12 August 2018 (has links)
Orientador: Yoshitaka Gushikem / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-12T16:49:45Z (GMT). No. of bitstreams: 1 Magosso_HericaAparecida_D.pdf: 835979 bytes, checksum: 2898b43a1168c04ffdef965b55b067fa (MD5) Previous issue date: 2008 / Resumo: Este trabalho reporta a preparação, caracterização e aplicação de novos polímeros íon-trocadores denominados cloreto de 3-n-propil (3-metilpiridínio) silsesquioxano e cloreto de 3-n-propil (4-metilpiridínio) silsesquioxano, obtidos a partir da incorporação de quantidades variáveis de grupos metilpiridínio aos materiais. Os polímeros obtidos se mostraram insolúveis nos solventes mais comuns, inclusive água, o que representou uma vantagem, já que permitiu sua utilização na forma em que foram preparados, sem a necessidade de suportá-los sobre nenhum substrato sólido para serem utilizados. Os espectros de RMN C e infravermelho mostraram que as sínteses foram bem sucedidas. Os resultados de análise termogravimétrica mostraram que os materiais estudados são termicamente estáveis até valores próximos a 500 K, o que representa uma característica interessante dos materiais, já que o processo de regeneração dos mesmos envolve secagem a 373 K sob vácuo. Os polímeros obtidos a partir da incorporação do grupo funcional 3-metilpiridínio, denominados Si3-PicCl-A e Si3-PicCl-B, os quais se diferem somente pela quantidade de grupo funcionais fixados, apresentaram capacidades de troca iônica iguais a 1,91 e 0,90 mmol L, respectivamente, enquanto aqueles obtidos pela incorporação do grupo funcional 4-metilpiridínio, denominados Si4-PicCl-A e Si4-PicCl-B, apresentaram capacidades de troca iônica iguais a 1,46 e 0,81 mmol L, respectivamente. Os polímeros Si3-PicCl-B e Si4-PicCl-B foram usados no processo de adsorção de íons cobre e zinco de solução etanólica e o polímero Si4-PicCl-A foi usado na adsorção de íons mercúrio, cádmio e zinco de solução aquosa. A metodologia de cálculo utilizada para se obter os parâmetros de ajuste das isotermas de adsorção foi baseada no modelo dos centros bidentados fixos. Os resultados de adsorção obtidos mostraram a viabilidade do uso dos polímeros como eficientes materiais adsorventes. O último polímero reportado neste trabalho, denominado Si3-PicCl-A, foi aplicado no desenvolvimento de um sensor amperométrico altamente sensível a nitrito. Os resultados obtidos mostraram a viabilidade da aplicação do material no desenvolvimento de um novo sensor para a aplicação proposta / Abstract: This work reports the preparation, characterization and applications of the new ion-exchanger polymers named 3-n-propyl(3-methylpyridinium) silsesquioxane chloride and 3-n-propyl(4-methyl pyridinium) silsesquioxane chloride prepared by the fixation of different amounts of methylpyridinium groups into the materials. The obtained materials were insoluble in the most common solvents, including water. This property was considered as an advantage since it allowed their use as prepared, without the necessity to be supported on the solid substract surface before using. The C NMR and infrared spectra showed that the syntheses were successfully. Thermogravimetric analysis showed that the obtained materials are thermally very stable up to 500 K, an important characteristic since their regeneration process, after using, includes drying the solid at temperature of 373 K under low pressure. The two obtained materials having as functional group the 3-methylpyridinium ion, named Si3-PicCl-A and Si3-PicCl-B, which differ each other just by the amount of functional groups immobilized, presented ion exchanger capacity equal to 1.91 e 0.90 mmol L, respectively, and those obtained having as functional group the 4-methylpyridinium ion, named Si4-PicCl-A and Si4-PicCl-B, presented ion exchanger capacity equal to 1.46 e 0.81 mmol L, respectively. The materials Si3-PicCl-B and Si4-PicCl-B were used in the adsorption process of copper and zinc ions from ethanol solution and the polymer Si4-PicCl-A was used in the adsorption process of mercury, cadmium and zinc ions from aqueous solution. The calculation methodology used to obtain the fit parameters of the adsorption isotherms was based on the model of fixed bidentate centers. The obtained adsorption results showed the viability of using the polymers as efficient adsorvent materials. The last polymer reported in this work, named Si3-PicCl-A, was applied in the development of a highly sensitive amperometric sensor for nitrite. The obtained results showed the viability of the application of the material in the development of a new sensor for the proposed application / Doutorado / Quimica Inorganica / Doutor em Ciências
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Lokal provtagning och analys på rökgaskondensat för driftövervakning av tungmetallrening med jonbytarmassor

Olofsson, Emelie January 2020 (has links)
I värme- och kraftvärmeverk förbränns olika typer av bränslen för produktion av el och fjärrvärme. Vid förbränningen bildas rökgaser som innehåller föroreningar, till exempel tungmetaller, från bränslet. Anläggningarna har ofta krav på utsläpp både via rökgaserna och avloppsvatten. Rökgaserna renas därmed genom olika tekniker var av en vanlig teknik är rökgaskondensering. Vid rökgaskondenseringen bildas en vätska, kallad rökgaskondensat, som delvis innehåller tungmetaller från bränslet. Rökgaskondensatet måste renas innan det kan lämna anläggningen och det görs bland annat med tungmetalljonbytare. Jonbytarmassan i tungmetalljonbytarkolonnerna behöver bytas ungefär två gånger per driftsäsong då den inte längre kan binda mer tungmetaller. Detta är en kostnad för värme- och kraftvärmeverken som de vill minimera. I denna studie undersöktes om lokal provtagning och analys på ett kraftvärmeverk av ett antal utvalda tungmetaller i rökgaskondensat är en bra metod för att optimering av reningssteget med tungmetalljonbytare. Samt om detta kan säkerställa att miljökraven för tungmetaller i det renade rökgaskondensatet uppfylls. Med optimering avses att jonbytarmassornas fulla kapacitet utnyttjas, d.v.s. att byten av jonbytarmassor kan reduceras utan att riskera otillåtna halter av tungmetaller i de renade rökgaskondensatet till följd av att jonbytarmassorna använts för länge. Även tiden som behöver avsättas för lokal provtagning och analys dokumenterades. I dagsläget sker analyser hos ackrediterade laboratorium där det tar drygt två veckor att få resultatet och under väntetiden kan mycket på anläggningen förändras. En verifiering av resultaten från studien gjordes mot resultat från ett sådant. I denna studie undersöktes lokal provtagning och analys med mätinstrumentet FREEDD som bygger på tekniken kvartskristall mikrobalans (QCM-teknik). Andra alternativ för lokal analys har inte undersökts här.  Resultatet visade att det i dagsläget är svårt att med lokal provtagning optimera reningssteget med jonbytarmassor samt kontrollera utsläppen av tungmetaller via det renade rökgaskondensatet. Korrigeringar hos mätinstrumentet och provpunkterna behöver göras för att få pålitligt resultat. Tiden som behöver avsättas för provtagning och analys beror på vilken metall som ska analyseras då tiden för preparering av prov varierar. Men om det kan möjliggöra att anläggningarna kan använda jonbytarmassorna längre samt får kontroll på utsläppen via det renade rökgaskondensatet kan det vara lönsamt att avvara den tiden. / In heating and combined heat and power plants, different types of fuels are burned to produce electricity and district heating. During the combustion flue gases containing pollutants, such as heavy metals, are formed from the flue. The plants have requirements for low emissions, both from the flue gases and the wastewater. The flue gases are purified by various techniques and a common technique is flue gas condensation. During the flue gas condensation, a liquid called flue gas condensate, is formed, which partly contains heavy metals from the flue. The flue gas condensate must be cleaned before it can leave the plant. A step in the purification of the flue gas condensate is usually heavy metal ion-exchanger. The ion-exchange mass in the heavy metal ion-exchange columns needs to be changed approximately twice per operating season as it no longer has room to bind more heavy metals. This is an expensive cost for the heating and combined heat and power plants that they want to minimize. This study investigated whether local sampling and analysis at a cogeneration plant of a number selected heavy metals in flue gas condensate is a good method for optimizing the purifications step with heavy metal ion-exchangers. And if this can ensure that the environmental requirements for the heavy metals in the purified flue gas condensate are met. Optimization means that the full capacity of the ion-exchange masses is utilized, i.e. that the exchange of ion-exchange masses can be reduced without risking unauthorized levels of heavy metals in the purified flue gas condensate as a result of the ion exchange masses being used for too long.  The time needed for local sampling and analysis was also documented. At present, analyzes are done at accredited laboratories where it takes over two weeks to get the result and during that time much can be changes at the plant. A verification of the result of the study was also made against the result of an accredited laboratory. In this study, local analysis was made with the measuring instrument FREEDD which is based on quartz crystal microbalance (QCM-technology). Other options for local sampling and analysis have not been investigated. The result showed that, in the present, it is difficult to optimize the purification step with ion-exchange masses and check emissions of heavy metals with the purified flue gas condensate. To obtain reliable result, corrections to the measuring instrument and test points need to be made. The time that needs to be set aside for sampling and analysis depends on the metal, as the time for sample preparation varies.  But if it can enable the plants to use the ion-exchange masses longer and gain control of the emissions of heavy metals with the purified flue gas condensate, it can be profitable to save that time.

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