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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

Potencijal primene stabilisanog i „zelenom“ sintezom produkovanog nano gvožđa (0) za remedijaciju sedimenta kontaminiranog metalima / Potential application of stabilized and "green" produced nano zero -valent iron for remediation of sediment contaminated with metals

Slijepčević Nataša 02 October 2020 (has links)
<p>Ekolo&scaron;ki&nbsp; problem&nbsp; svetskih&nbsp; razmera&nbsp; predstavlja&nbsp; zagađenost&nbsp; sedimenta&nbsp; te&scaron;kim&nbsp; metalima, usled negativnih ekolo&scaron;kih efekata metala na životnu sredinu. Mnoge zemlje i regioni, kao i na&scaron;a zemlja&nbsp; suočavaju&nbsp; se&nbsp; sa&nbsp; ovom&nbsp; problematikom,&nbsp; koja&nbsp; je&nbsp; vrlo&nbsp; rasprostranjena&nbsp; usled&nbsp; sve&nbsp; brže urbanizacije&nbsp; i&nbsp; industrijalizacije,&nbsp; a&nbsp; sa&nbsp; sve&nbsp; većom&nbsp; nebrigom&nbsp; usled&nbsp; ispu&scaron;tanja&nbsp; otpadnih&nbsp; voda&nbsp; bez prethodnog&nbsp; preči&scaron;ćavanja&nbsp; u&nbsp; vodotokove.&nbsp; Prilikom&nbsp; promene&nbsp; uslova&nbsp; vodenog&nbsp; ekosistema,&nbsp; može doći do&nbsp; izluživanja&nbsp; metala&nbsp; i &scaron;tetnih efekata na&nbsp; životnu sredinu kao&nbsp; i&nbsp; na zdravlje&nbsp; ljudi. Stoga je remedijacija sedimenata zagađenih metalima ključna aktivnost u okviru procesa potpune sanacije vodenog ekosistema, a ekonomične, efikasne i ekolo&scaron;ki prihvatljive tehnike remedijacije su hitno potrebne&nbsp; i&nbsp; rado&nbsp; primenljive&nbsp; u&nbsp; tretmanu&nbsp; na&nbsp; velikoj&nbsp; skali.&nbsp; Pre&nbsp; primene&nbsp; remedijacione&nbsp; tehnike&nbsp; na velikoj skali, neophodna su ispitivanja pri laboratorijskim uslovima i pilot skali.&nbsp; Na kraju svakog uspe&scaron;nog&nbsp; laboratorijskog&nbsp; ispitivanja&nbsp; nalaze&nbsp; se&nbsp; pilot&nbsp; istraživanja.&nbsp; Pomoću&nbsp; njih&nbsp; se&nbsp; dobija&nbsp; p ravi odgovor u smislu izbora optimalne tehnologije imajući u vidu investicione i operativne tro&scaron;kove,<br />postignuti rezultat i krajnje ciljeve u pogledu upravljanja postrojenjem i otpadom. U ovom radu ispitan&nbsp; je&nbsp; potencijal&nbsp; primene&nbsp; stabilisanog&nbsp; i&nbsp; zelenom&nbsp; sinte zom&nbsp; produkovanog&nbsp; nano&nbsp; Fe(0)&nbsp; zaremedijaciju&nbsp; sedimenta&nbsp; zagađenog&nbsp; te&scaron;kim&nbsp; metalima.&nbsp; Kao&nbsp; remedijaciona&nbsp; tehnika&nbsp; odabrana&nbsp; je stabilizacija/solidifikacija,&nbsp; koja&nbsp; podrazumeva&nbsp; dodavanje&nbsp; agenasa&nbsp; za&nbsp; imobilizaciju&nbsp; metala&nbsp; u sedimentu&nbsp; sprečavajući&nbsp; time&nbsp; potencijalni&nbsp; rizik&nbsp;&nbsp; od&nbsp; izluživanja&nbsp; metala&nbsp; u&nbsp; životnu&nbsp; sredinu. Konvencionalni&nbsp; materijali&nbsp; poput&nbsp; letećeg&nbsp; pepela,&nbsp; cementa,&nbsp; gline&nbsp; se&nbsp; već&nbsp; odavno&nbsp; koriste&nbsp; u&nbsp; ovu svrhu. Kako u dana&scaron;nje vreme raste potražnja za novim, lako dostupnim agensima za stabilizaciju<br />sedimenta, do&scaron;lo se na ideju o primeni nanomaterijala na bazi gvožđa, tj. nano Fe(0) stabilisanog nativnom glinom&nbsp; i produkovanog redukcijom pomoću organskih&nbsp; molekula prirodno prisutnih u ekstraktu&nbsp; li&scaron;ća&nbsp; hrasta&nbsp; i&nbsp; crnog&nbsp; duda.&nbsp; Nanomaterijali&nbsp; su&nbsp; sintetisani&nbsp; i&nbsp; karakterisani&nbsp; različitim metodama&nbsp; i&nbsp; tehnikama.&nbsp; U&nbsp; nastavaku,&nbsp; u&nbsp; cilju&nbsp; efikasnosti&nbsp; njihove&nbsp; primene&nbsp; za&nbsp; stabilizaciju sedimenta, sprovedeni su ekstrakcioni i dinamički laboratorijski testovi izluživanja. Odabrane su sme&scaron;e sedimenta i nanomaterijala koje su pokazale najbolju efikasnost tr etmana. Nakon toga se ispitivanje&nbsp; nastavilo&nbsp; na&nbsp; pilot&nbsp; skali,&nbsp; gde&nbsp; se&nbsp; pratilo&nbsp; pona&scaron;anje&nbsp; nanomaterijala&nbsp; u&nbsp; zavisnosti&nbsp; od konvencionalnih&nbsp; materijala&nbsp; koji&nbsp; su&nbsp; već&nbsp; u&nbsp; literaturi&nbsp; dokumentovani&nbsp; kao&nbsp; efikasni&nbsp; imobilizacioni agensi. Dodatna potvrda uspe&scaron;nosti tretmana data je analizom i karakterizacijom s/s sme&scaron;a nakon pilot&nbsp; ispitivanja&nbsp; Na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata&nbsp; proces&nbsp; se&nbsp; uspe&scaron;no&nbsp; pokazao&nbsp; pri&nbsp; laboratorijskim uslovima,&nbsp; a&nbsp; takođe&nbsp; i&nbsp; prilikom&nbsp; pilot&nbsp; tretmana,&nbsp; odnosno&nbsp; nakon&nbsp; pilot&nbsp; tretmana&nbsp; nije&nbsp; do&scaron;lo&nbsp; do povećanih koncentracija&nbsp; izluživanja metala iz s/s sme&scaron;a, kao ni degradacije sme&scaron;a nakon procesa ovlaživanja&nbsp; tokom&nbsp; &scaron;est&nbsp; meseci.&nbsp; Na&nbsp; osnovu&nbsp; toga,&nbsp; ovako&nbsp; tertirani&nbsp; sediment&nbsp; se&nbsp; može&nbsp; bezbedno odlagati&nbsp; na&nbsp; deponije,&nbsp; ili&nbsp; pak&nbsp; iskoristiti&nbsp; za&nbsp; &bdquo;kontrolisanu&ldquo;&nbsp; upotrebu,&nbsp; izgradnju&nbsp; puteva,kamenoloma, pomoćnih objekata i slično. Rezultati su doprineli u cilju trajnijeg re&scaron;avanja pitanja odlaganja&nbsp; zagađenog&nbsp; (izmuljenog)&nbsp; rečnog&nbsp; sedimenta,&nbsp; pri&nbsp; čemu&nbsp; se&nbsp; u&nbsp; procesu stabilizacije/solidifikacije&nbsp; dobijaju&nbsp; proizvodi&nbsp; sa&nbsp; dodatom&nbsp; vredno&scaron;ću&nbsp; neumanjenog&nbsp; kvaliteta .Nanomaterijali sintetisani u ovom radu na&nbsp; bazi ekstrakta li&scaron;ća biljaka doprinose kako očuvanju životne&nbsp; sredine,&nbsp; tako&nbsp; i&nbsp; ekonomičnosti&nbsp; primene&nbsp; remedijacione&nbsp; tehnike.&nbsp; Zahvaljujući&nbsp; velikoj specifičnoj&nbsp; povr&scaron;ini,&nbsp; malim&nbsp; dimenzijama&nbsp; čestica&nbsp; i&nbsp; velikom&nbsp; kapacitetu&nbsp; za&nbsp; imobilizaciju&nbsp; te&scaron;kih<br />metala predstavljaju efikasnu alternativu komercijalno dostupnim materijalima, &scaron;to ih čini veoma atraktivnim&nbsp; i&nbsp; obećavajućim&nbsp; u&nbsp; budućnosti&nbsp; pri&nbsp; tretmanu&nbsp; rečnog&nbsp; sedimenta&nbsp; zagađenog&nbsp; te&scaron;kim metalima.</p> / <p>The pollution of sediment by heavy metals represents a large environmental problem all<br />over the world.&nbsp; A&nbsp; lot of countries&nbsp; in the region&nbsp; as well as our country deal with this problem, which&nbsp; is&nbsp; widespread&nbsp; because&nbsp; of&nbsp; the&nbsp; fast&nbsp; urbanization&nbsp; and&nbsp; industrialization.&nbsp; There&nbsp; is&nbsp; more&nbsp; and more&nbsp; carelessness&nbsp; about&nbsp; wastewater&nbsp; discharge&nbsp; into&nbsp; water&nbsp; flows&nbsp; without&nbsp; previous&nbsp; purification. When the conditions of the aquatic ecosystem change, metal leaching and harmful effects on the environment&nbsp; and&nbsp; human&nbsp; health&nbsp; can&nbsp; occur.&nbsp; Therefore,&nbsp; remediation&nbsp; of&nbsp; metal-contaminated sediments&nbsp; is&nbsp; crucial&nbsp; activity&nbsp; in&nbsp; the&nbsp; process&nbsp; of&nbsp; the&nbsp; complete&nbsp; ecosystem&nbsp; remediation.&nbsp; Cost effective, efficient and environmentally friendly remediation techniques are urgently needed and readily applicable in large-scale treatment. Before applying remediation techniques on the largescale,&nbsp; both&nbsp; laboratory&nbsp; and&nbsp; pilot&nbsp; tests&nbsp; are&nbsp; necessary.&nbsp; There&nbsp; are&nbsp; pilot&nbsp; studies&nbsp; at&nbsp; the&nbsp; end&nbsp; of&nbsp; each successful&nbsp; laboratory&nbsp; test.&nbsp; Those&nbsp; studies&nbsp; provide&nbsp; the&nbsp; right&nbsp; answer&nbsp; in&nbsp; terms&nbsp; of&nbsp; choosing&nbsp; the optimal technology, taking into account the investment and operating costs,&nbsp;&nbsp; the achieved resultand&nbsp; the&nbsp; ultimate&nbsp; goals&nbsp; in&nbsp; terms&nbsp; of&nbsp; plant&nbsp; and&nbsp; waste&nbsp; management.&nbsp; In&nbsp; this&nbsp; study,&nbsp; the&nbsp; application<br />potential of stabilized and green&nbsp; -&nbsp; synthesized&nbsp; nano Fe(0) for the remediation of&nbsp; heavy&nbsp; metal&nbsp; -contaminated&nbsp; sediment&nbsp; was&nbsp; investigated.&nbsp; Stabilization&nbsp; /&nbsp; solidification&nbsp; technique&nbsp; was&nbsp; chosen&nbsp; as remediation technique which involves the addition of metal immobilizing agents in the sediment thus preventing the potential risk of metal leaching into the environment. Conventional materials such as fly ash, cement and clay have long been used for this purpose. Nowadays there is need for new, easily accessible agents for the sediment stabilization. Therefore it came up with the idea of&nbsp; using&nbsp; iron-based&nbsp; nanomaterials,&nbsp; ie.&nbsp; nano&nbsp; Fe(0)&nbsp; stabilized&nbsp; by&nbsp; native&nbsp; cla y&nbsp; and&nbsp; produced&nbsp; by reduction&nbsp; using&nbsp; organic&nbsp; molecules&nbsp; naturally&nbsp; present&nbsp; in&nbsp; oak&nbsp; and&nbsp; black&nbsp; mulberry&nbsp; leaf&nbsp; extract. Nanomaterials have been synthesized and characterized by different methods and techniques. In order&nbsp; to&nbsp; be&nbsp; effective&nbsp; in&nbsp; their&nbsp; application&nbsp; for&nbsp; sediment&nbsp; stabilization,&nbsp; extraction&nbsp; and&nbsp; dynamic laboratory leaching tests were performed. Mixtures of sediment and nanomaterials were selected that showed the best treatment efficiency.&nbsp; After that, the examination was continued on a pilot scale, where the behavior of nanomaterials was monitored, depending on conventional materials which&nbsp; have&nbsp; already&nbsp; been&nbsp; documented&nbsp; in&nbsp; the&nbsp; literature&nbsp; as&nbsp; effective&nbsp; immobilizing&nbsp; agents.Additional confirmation of treatment success was given by analysis and characterization of s / s mixtures&nbsp; after&nbsp; pilot&nbsp; testing.&nbsp; According&nbsp; to&nbsp; obtained&nbsp; results,&nbsp; the&nbsp; process&nbsp; was&nbsp; successfully demonstrated&nbsp; under&nbsp; laboratory&nbsp; conditions,&nbsp; and&nbsp; also&nbsp; during&nbsp; the&nbsp; pilot&nbsp; treatment.&nbsp; After&nbsp; the&nbsp; pilot treatment&nbsp; there&nbsp; were&nbsp; no&nbsp; increased&nbsp; concentrations&nbsp; of&nbsp; metal&nbsp; leaching&nbsp; from&nbsp; s/s&nbsp; mixtures,&nbsp; nor mixture degradation after the wetting process for six months. Based on that, the sediment treated in this way&nbsp; can&nbsp; be safely disposed of&nbsp; in&nbsp; landfills, or used&nbsp; for &quot;controlled&quot; use, construction of<br />roads,&nbsp; quarries,&nbsp; auxiliary&nbsp; facilities&nbsp; and&nbsp; etc.&nbsp; The&nbsp; results&nbsp; have&nbsp; contributed&nbsp; to the&nbsp; goal&nbsp; of&nbsp; a&nbsp; more permanent solution to the issue of disposal of polluted (slugged) river sediment, whereby in the process&nbsp; of&nbsp; stabilization/solidification,&nbsp; products&nbsp; with&nbsp; added&nbsp; value&nbsp; of&nbsp; undiminished&nbsp; quality&nbsp; are obtained. The nanomaterials synthesized in this paper on the basis of plant leaf extract contribute to both the preservation of the environment and the economy of remediation techniques. Thanks to their&nbsp; large specific&nbsp; surface area, small particle size and&nbsp; large ca pacity&nbsp; for&nbsp; immobilization of heavy&nbsp; metals,&nbsp; they&nbsp; represent&nbsp; an&nbsp; effective&nbsp; alternative&nbsp; to&nbsp; commercially&nbsp; available&nbsp;&nbsp; materials.&nbsp; It makes&nbsp; them&nbsp; very&nbsp; attractive&nbsp; and&nbsp; promising&nbsp; in&nbsp; the&nbsp; future&nbsp; in&nbsp; the&nbsp; treatment&nbsp; of&nbsp; river&nbsp; sediment contaminated with heavy metals.</p>
2

Electrosynthèse assistée par ultrasons de nanoparticules de fer à valence zéro : étude de la croissance de dépôts et de leur dispersion par ondes acoustiques / Ultrasounds assisted electrosynthesis of zero valence iron nanoparticles : study of the deposit growth and dispersion by acoustic waves

Iranzo, Audrey 25 November 2016 (has links)
La synthèse de nanoparticules de fer zéro-valent, par le couplage des procédés d'ultrasonication et d'électrodéposition, est étudiée selon deux approches. La première partie de l'étude s'intéresse à l'influence du substrat, utilisé pour l'électrodéposition, sur la croissance des dépôts de fer et sur leur dispersion par ultrasonication. L'énergie interfaciale ainsi que l'énergie d'adhésion du dépôt sur le substrat (Y_(Fe/substrat) et W_(Fe/substrat) respectivement) étant reliées à l'énergie de surface et à la rugosité du substrat, un intérêt particulier a été porté à ces deux propriétés. Ainsi, deux matériaux présentant des énergies de surface différentes, l'or (Au) et le carbone vitreux (VC), ainsi que des rugosités différentes ont été testés. Un développement théorique basé sur les interactions de Van der Waals a permis de démontrer que Y_(Fe/VC)>Y_(Fe/Au) ce qui suggère une meilleure affinité du dépôt de fer avec l'or qu'avec le VC. Cette différence influence la morphologie (croissance 2D sur or et 3D sur le VC) mais aussi l'adhésion des dépôts. En effet, les expériences réalisées pour étudier l'effet des ultrasons sur le dépôt de fer révèlent une dispersion du dépôt progressive et complète pour le cas du VC alors qu'aucun détachement du dépôt n'est obtenu en utilisant l'or. La seconde partie de l'étude est consacrée à la synthèse de nanoparticules de fer par une nouvelle approche : l'électrodéposition de dépôts de fer ramifiés est étudiée dans une cellule de Hele-Shaw intégrant un élément vibrant (diaphragme piézoélectrique) permettant à la fois la formation de dépôts de fer et leur fragmentation. Les expériences menées révèlent que les bulles d'hydrogène, formées lors de la co-réduction des protons libres durant l'électrodéposition du fer, influencent fortement le processus de fragmentation. En utilisant des hautes fréquences et amplitudes de vibration du PZT, les bulles d'hydrogène oscillent avec des déformations de surface. Celles-ci génèrent des vitesses d'interface suffisamment hautes (˜ 4 m/s) pour permettre aux bulles de fragmenter des dépôts ramifiés en particules de fer, de tailles comprises entre 1 µm et 100 nm, et présentant une grande surface spécifique due à leur morphologie dendritique. Cette deuxième partie de l'étude permet d'ouvrir la voie à une nouvelle technologie de fabrication des nanoparticules. / This study concerns the coupling of the ultrasounds with the electrodeposition process for the synthesis of zero-valent iron nanoparticles; it is structured in two sections. The first focuses on the electrode substrate used for the iron electrodeposition and aims to determine its influence on both the deposit growth and its dispersion by ultrasonication. The interfacial and the adhesion energies of the deposit on the substrate (Y_(Fe/substrate) and W_(Fe/substrate) respectively) being related to the surface energy and the roughness of the substrate, a particular focus is put on the influence of these two properties. Thus, two materials of different surface energies, gold (Au) and vitreous carbon (VC), as well as various roughnesses, are tested. Considering only the Van der Waals interactions, a theoretical development has enabled to determine that Y_(Fe/VC)>Y_(Fe/Au) which suggests a better affinity of the iron deposit with the gold than with the VC substrate. This difference impacts the deposit morphology (2D growth on the gold and 3D growth on the VC substrate) but also the deposit adhesion. Indeed, experiments performed to study the effect of ultrasounds on the iron electrodeposit reveal its progressive and complete dispersion for the vitreous carbon case while no dispersion (no removal of the deposit from the electrode) is obtained with the gold substrate. The second section of the present study deals with the synthesis of iron nanoparticles; to this end, the electrodeposition of branched deposits has been investigated in a Hele-Shaw cell integrating a vibrating element (piezoelectric diaphragm), expected to allow both the deposit formation and its fragmentation. Experiments reveal that the hydrogen bubbles, formed by the co-reduction of free protons during the iron electrodeposition, strongly influence the fragmentation process. Using high vibration frequencies and high amplitudes, the bubbles oscillate with surface deformations, inducing interface velocity sufficiently high (˜ 4 m/s) to allow the fragmentation of the deposit into particles of sizes ranging between 1 µm and 100 nm and showing a high specific surface due to their dendritic morphology. Thus this work opens the way for a new particles manufacturing technology.
3

S?ntese e caracteriza??o do comp?sito ferro zero-valente nanoparticulado/carv?o ativado granulado (nFZV-CAG) e sua aplica??o para remo??o do f?rmaco nimesulida pelos processos adsor??o/redu??o e ozoniza??o catal?tica heterog?nea

Oliveira, Fernanda Gandra de 13 September 2016 (has links)
"Resumo/Abstract", "palavras-chave/keywords" nos cap?tulos trabalho. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-03-27T20:52:05Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) fernanda_gandra_oliveira.pdf: 3187185 bytes, checksum: 690bd6e7967bbab89412d221de93c88a (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-04-24T14:26:09Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) fernanda_gandra_oliveira.pdf: 3187185 bytes, checksum: 690bd6e7967bbab89412d221de93c88a (MD5) / Made available in DSpace on 2017-04-24T14:26:09Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) fernanda_gandra_oliveira.pdf: 3187185 bytes, checksum: 690bd6e7967bbab89412d221de93c88a (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / O comp?sito nFZV-CAG foi empregado para a ozoniza??o catal?tica heterog?nea da NMS em meio aquoso. O oz?nio foi gerado por uma central geradora de oz?nio IPABRAS, alimentada com ar. Foram avaliados diferentes processos catal?ticos como O3, CAG, O3-CAG, O3-nFZV- CAG, e a varia??o da concentra??o das nFZV para remo??o da NMS. Os resultados mostraram que a combina??o do O3-nFZV-CAG foi muito eficiente levando ? mineraliza??o de aproximadamente 70% da NMS em 120 min de rea??o. Tal efici?ncia pode estar atribu?da ao processo de eletr?lise, em que o Fe0 origina Fe2+ levando ? produ??o do radical hidroxila que ? altamente oxidante, levando a destrui??o do contaminante. As rea??es seguiram a cin?tica pseudo-primeira ordem para remo??o do f?rmaco. Ap?s realizada a coleta as amostras foram submetidas a an?lise qu?mica, empregando-se as t?cnicas de espectrofotometria de UV-Vis, cromatografia l?quida de alta efici?ncia (CLAE) e a determina??o da demanda qu?mica de oxig?nio (DQO) tamb?m foi realizada. / As nanopart?culas de FZV imobilizadas sobre a superf?cie do carv?o ativado (nFZV-CAG) foram sintetizadas e caracterizadas para remo??o do f?rmaco Nimesulida (NMS) em sistemas aquosos. Os estudos foram realizados em bateladas com agita??o de 250 rpm durante 120 minutos, onde foram avaliadas a efici?ncia, concentra??o (20, 25 e 30% do comp?sito) e diferentes dosagens (0,1 a 10g) de nFZV-CAG. Os resultados mostraram que a dosagem de 10 g de 20%nFZV-CAG removeu cerca de 80% da NMS 50 mg L-1 em apenas 30 minutos de rea??o, e atingindo 100% em 120 minutos. Foi observada ainda uma remo??o de 80% da DQO ao final da rea??o. As velocidades de rea??o aumentaram na medida em que foram aumentadas as dosagens do comp?sito, o que seria esperado. Por?m, com o aumento da concentra??o (%) de nFZV n?o houve aumento na velocidade das rea??es. As rea??es seguiram uma cin?tica de pseudo-primeira ordem em rela??o ? remo??o da NMS. Ap?s realizada a coleta, as amostras foram submetidas a an?lise qu?mica, empregando-se as t?cnicas de espectrofotometria de UV- VIS, cromatografia l?quida de alta efici?ncia (CLAE) e a determina??o da demanda qu?mica de oxig?nio (DQO) tamb?m foi realizada. Para caracteriza??o do comp?sito foram empregadas as t?cnicas Microscopia Eletr?nica de Varredura acoplada ? Espectrometria de Energia Dispersiva de Raios-X (MEV-EDS), que mostraram claramente a presen?a da nanopart?culas sobre a superf?cie do carv?o, e analise de superf?cie do nFZV-CAG e do CAG tamb?m foram realizadas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The FZV nanoparticles immobilized onto the surface of the activated charcoal (nFZV-CAG) were synthesized and characterized for the removal of the pharmaceutical Nimesulide (NMS) in aqueous systems. The studies were performed in batch mode with stirring speeds of 250 rpm during 120 minutes, so that it was possible to evaluate efficiency, concentration (20, 25 and 30% of the composite) and different dosages (0,1 to 10g) of nFZV-CAG. The results showed that the dosage of 10g of 20%nFZV-CAG removed approximately 80% of NMS 50 mg L-1 in just 30 minutes of reaction, and reaching 100% in 120 minutes. It was still observed a removal of 80% of the COD (Chemical Oxygen Demand) at the end of the reaction. The reaction rates increased with the dosage of the composite, which was expected. Though, increasing the concentration (%) of nFZV did not result in higher reaction rates. The reactions followed a pseudo-first order kinetics for the removal of NMS. After the samples were collected, they were submitted to chemical analysis, employing the techniques of UV-VIS spectroscopy, high performance liquid chromatography (HPLC) and chemical oxygen demand (COD). In order to characterize the composite, the following techniques were used: Scanning Electron Microscopy (SEM) coupled with Energy Dispersive x-Ray spectroscopy (EDS), which showed clearly the presence of nanoparticles onto the charcoal surface. Analysis of the surface of nFZV-CAG were also performed. / The composite nFZV-CAG was used for the catalytic ozonation of NMS in aqueous media. The ozone was generated by an ozone generator IPABRAS, fuelled with air. Different catalytic processes were evaluated such as O3, CAG, O3-CAG, O3-nFZV-CAG, and the variation of the nFZV concentration for the removal of NMS. The results showed that the combination of O3- nFZV-CAG was very efficient, leading to the mineralization of approximately 70% of NMS in 120 minutes of reaction. Such efficiency can be attributed to the electrolysis process, in which the Fe0 generates Fe2+ which generates hydroxyl radicals that are highly oxidant, leading to the destruction of the contaminant. The reactions followed the pseudo-first order kinetics for the removal of the pharmaceutical. After the samples were collected, they were submitted to chemical analysis such as, UV-VIS spectroscopy, high performance liquid chromatography (HPLC) and chemical oxygen demand (COD).

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