Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-10T20:59:54Z No. of bitstreams: 1 IsabelDoNascimentoSilva_DISSERT.pdf: 2418735 bytes, checksum: ca16004dc66af3d5c11335f42a833675 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-12T20:15:13Z (GMT) No. of bitstreams: 1 IsabelDoNascimentoSilva_DISSERT.pdf: 2418735 bytes, checksum: ca16004dc66af3d5c11335f42a833675 (MD5) / Made available in DSpace on 2016-05-12T20:15:13Z (GMT). No. of bitstreams: 1 IsabelDoNascimentoSilva_DISSERT.pdf: 2418735 bytes, checksum: ca16004dc66af3d5c11335f42a833675 (MD5) Previous issue date: 2015-07-15 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Com o crescente desenvolvimento cient?fico e tecnol?gico, o homem passa a explorar os recursos naturais de forma mais agressiva, gerando diariamente grandes quantidades de res?duos que s?o descartados no meio ambiente sem nenhum tratamento pr?vio. As institui??es de ensino e pesquisa v?m ganhando destaque como poluidoras do ambiente, j? que ignoram sua condi??o de geradoras de efluentes e descartam seus res?duos qu?micos de forma inadequada. Dentre os principais contaminantes ambientais, os corantes ganham destaque, pois se tratam de subst?ncias altamente t?xicas para a fauna e flora aqu?tica, podendo causar s?rios danos ? sa?de humana. Muitas t?cnicas no tratamento de efluentes contendo corantes v?m sendo apresentados na literatura, dentre as quais se destaca a adsor??o que vem sendo utilizada de forma eficaz no tratamento desses efluentes. O baba?u, palmeira nativa da Am?rica latina ? amplamente encontrada em alguns estados do norte, nordeste e centro-oeste do Brasil, produz um fruto que possui uma vasta potencialidade, dentre as quais se destaca a produ??o de carv?o. Assim, este trabalho tem como objetivo utilizar o carv?o de coco de baba?u modificado com ?cido c?trico (CCBMod) para tratar o efluente real gerado a partir do uso do corante azul de metileno (AM). Para caracterizar o CCBMod utilizou-se as t?cnicas de Espectroscopia de absor??o molecular na regi?o do Infravermelho (IV), Difra??o de raios-X (DRX), Termogravimetria e An?lise T?rmica Diferencial (TG/DTA) e Microscopia Eletr?nica de Varredura (MEV). O IV mostrou a presen?a de grupos OH, CH2, CH3 e C=O tanto no material modificado quando no material sem modifica??o, grupos estes caracter?sticos da lignina, no entanto n?o se verificou nenhuma incorpora??o do ?cido c?trico no material, dados que foram comprovados pelas demais t?cnicas. Assim infere-se que o ?cido usado na modifica??o foi eficiente na ativa??o dos s?tios dispon?veis do carv?o, melhorando o processo de adsor??o no decorrer do tempo. Na varia??o da concentra??o inicial do adsorvente, observou-se que o percentual de remo??o da cor do AM aumenta com a diminui??o da concentra??o inicial, onde nas concentra??es de 14, 12, 10, 8, 6, 4 e 2 mg L-1 apresentou valores m?dios de remo??o correspondendo respectivamente a 56,13; 62,43; 62,70; 70,00; 87,00; 93,83 e 100 %. Para a varia??o do pH da solu??o, observou-se que com o aumento do pH aumenta-se o percentual de remo??o da cor, assim para os potenciais hidrogeni?nicos 3,0; 6,0 e 10,0 obteve-se respectivamente, 39,73; 62,69 e 92,74 % de remo??o do AM. O modelo de cin?tica de adsor??o que melhor se ajustou aos dados experimentais foi o de pseudo-segunda-ordem, apresentando um valor de r2 igual 0,9965 e valores de qe,exp de 1,5424 mg g-1 e qe,teor de 1,5625 mg g-1. O modelo isot?rmico que melhor se ajustou aos dados experimentais foi o de Langmuir indicando uma natureza de adsor??o em monocamada. O efluente real proposto apresentou uma decomposi??o do AM de 7,20 % no decorrer de 14 dias e a remo??o desse efluente real pelo CCBMod foi de 57,86%. Concluindo-se que o CCBMod ? um material adsorvente eficaz na remo??o do AM de solu??es aquosas. / With the growing scientific and technological development, the man begins to exploit natural resources more aggressively, generating daily huge amounts of waste that are discarded into the environment without any prior treatment. Higher educational and research institutions have been gaining emphasis as environmental polluters, since ignore their condition waste generators and discard their chemical waste improperly. Among the main environmental contaminants, the dyes gain prominence, because they are highly toxic substance to aquatic plants and animals, causing serious damage to human health. Many techniques for the treatment of wastewater containing dyes have been reported in the literature, among them the adsorption has been used of way effective in the treatment of these effluents containing dyes. The babassu, palm tree native of Latin America is widely found in some northern, northeast and center-west states of Brazil, produces a fruit that has a vast potential, among which stands out the production of coal. This work aims to use the babassu coconut carbon (BCC) modified with citric acid to treat real effluent generated from methylene blue (MB) dye. In order to characterize the BCC modified were used the techniques of molecular absorption spectroscopy in infrared region (IR), X-ray Diffraction (XRD), thermal analysis (TG/ DTA) and Scanning Electron Microscopy (SEM). The IR showed the presence of groups OH, CH2, CH3 and C=O in both the materials modified and without modification, these groups are characteristic of lignin. It is also noted that the acid treatment promoted a modified on carbon surface, decreasing the heterogeneity of the same. Data were confirmed by other techniques. Thus it is inferred that the acid used in the modification was effective in activation of the available carbon sites, improving adsorption process over time. Varying the initial concentration of the adsorbent, it was observed that the removal percentage of MB color increases with decreasing initial concentration, where the concentrations from 14 to2 mg L-1 showed maximum removal points corresponding respectively to 62,43; 62,70; 70,00; 87,00; 93,83 e 100 %. For the change in pH of the solution was observed that with an increase in pH increases the percentage of the MB removal color, so to pH 3.0; 6.0 and 10.0 was obtained respectively 93,60; 67.29 and 42.15% removal AM. The adsorption kinetics model that best fit the experimental data was the pseudo-second-order, with a r2 value of 0.9965 and qe,exp 1.5424 mg g-1 and qe,teor 1.5625 mg g-1. The isothermal model that best fit the experimental data was the Langmuir indicating adsorption in monolayer. Concluding the modified BCC was presented as an effective adsorbent material in the MB removal from aqueous solutions. The real effluent proposed presented a decomposition to AM of 7.20% over 14 days and the removal of this real effluent by CCBMod was 57.86%. Concluding CCBMod is an effective adsorbent material in the removal of AM from aqueous solutions.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-10T22:49:41Z No. of bitstreams: 1 HenaLissaDeSousaMedeiros_DISSERT.pdf: 2450139 bytes, checksum: 33f229e4eaf5df1a317d891b6b53240c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-17T22:45:27Z (GMT) No. of bitstreams: 1 HenaLissaDeSousaMedeiros_DISSERT.pdf: 2450139 bytes, checksum: 33f229e4eaf5df1a317d891b6b53240c (MD5) / Made available in DSpace on 2016-05-17T22:45:27Z (GMT). No. of bitstreams: 1 HenaLissaDeSousaMedeiros_DISSERT.pdf: 2450139 bytes, checksum: 33f229e4eaf5df1a317d891b6b53240c (MD5) Previous issue date: 2015-06-30 / Ag?ncia Nacional do Petr?leo - ANP / A ?gua produzida ? um dos principais res?duos gerados durante a explora??o e produ??o de petr?leo, devido ao grande volume e a sua composi??o qu?mica complexa surge ? preocupa??o para que as concentra??es dos contaminantes atendam as legisla??es vigentes, com a finalidade de reduzir os efeitos nocivos ao meio ambiente provocado pelo seu descarte sem tratamento pr?vio. Assim, o objetivo deste trabalho ? caracterizar a ?gua produzida no Campo de Periquito, do Estado do RN e avaliar o potencial adsortivo do carv?o vegetal de coco baba?u para remo??o dos metais Ca e Sr da ?gua produzida, visando a sua adequa??o para descarte. Atrav?s da caracteriza??o f?sico-qu?mica da ?gua produzida, p?de-se observar que as concentra??es dos metais c?lcio e estr?ncio foram: 322 mg/L e 69 mg/L, respectivamente. O material a ser utilizado como adsorvente foi caracterizado por diferentes t?cnicas f?sico-qu?micas, tais como: granulometria, densidade aparente, an?lise elementar, an?lise t?rmica, FRX, MEV, DRX e pHPZC. De posse das an?lises das caracteriza??es foram realizados ensaios de adsor??o, pelo m?todo de banho finito em solu??es sint?ticas dos metais Ca e Sr. Os resultados demonstraram que o carv?o baba?u possui remo??o m?xima em baixas concentra??es. Paralelamente ao estudo de adsor??o em solu??es sint?ticas, foi realizado ensaios de adsor??o com a ?gua produzida e o resultado mostrou que o carv?o baba?u possui bom potencial de adsor??o, removendo acima de 50 % do c?lcio e acima 45 % do estr?ncio, e apresentando valores para a capacidade de adsor??o de 17,31 mg/g para o c?lcio e 3,15 mg/g para o estr?ncio. Para otimizar os ensaios de adsor??o foi aplicado o planejamento fatorial completo de dois n?veis com o intuito de verificar a influ?ncia da concentra??o dos metais Ca e Sr e a massa do adsorvente em solu??o sint?tica sobre a % remo??o e a capacidade de adsor??o dos metais. Atrav?s dos resultados das an?lises das superf?cies de respostas p?de-se observar que as regi?es ?timas para a remo??o dos metais foram no n?vel superior da concentra??o dos metais e no n?vel superior da massa de adsorvente (+1,+1) obtendo uma remo??o m?xima de 58 % do c?lcio e 63 % do estr?ncio. / Produced water is a major waste generated during oil exploration and production. Due to its large volume and complex chemical composition an effort arises so that the contaminant concentrations meet the current legislation, in order to reduce harmful effects on the environment caused by its disposal without prior treatment. The objective of this paper is to characterize produced water from the Periquito field, RN, Brazil, and assess the adsorptive potential of babassu nut charcoal for removal of calcium and strontium from produced water, focusing on its suitability for disposal. Through the physicochemical characterization of the produced water, it was possible to observe that the concentrations of calcium and strontium were: 322 mg/L and 69 mg/L, respectively. The material to be used as an adsorbent was characterized through different physicochemical techniques, such as laser particle size, density, elemental analysis, thermal analysis, XRF, SEM, XRD and pHPZC. Provided the characterization analysis, adsorption experiments were carried out using the method of finite bath in synthetic solutions of both calcium and strontium. The results showed that babassu nut charcoal has maximum adsorption removal at low concentrations. In parallel with the study on adsorption in synthetic solutions, adsorption experiments were performed with produced water, whose results showed that babassu nut charcoal has good adsorption potential, removing over 50% of calcium and above 45% strontium, and having values of 17.31 mg/g for the adsorption capacity for calcium and 3.15 mg/g for strontium. In order to optimize the experiments, the full factorial design of two levels was applied in order to verify the influence of the concentration of calcium, strontium and the mass of the adsorbent in synthetic solution on the percentage of removal (%) and the adsorption capacity of adsorption of these metals. From the analysis results, it was possible to observe that the optimal regions for the removal of these metals was in the upper level of the metal concentration and in the upper level of the adsorbent mass (+1, +1) obtaining a maximum removal of 58 % for calcium and 63 % for strontium.

Made available in DSpace on 2014-12-17T14:06:55Z (GMT). No. of bitstreams: 1 FranciscoJPF.pdf: 1681554 bytes, checksum: 4238148885bafd3e26a8d8ca7de20466 (MD5) Previous issue date: 2010-08-07 / Nowadays the environmental issues are increasingly highlighted since the future of humanity is dependent on the actions taken by man. Major efforts are being expended in pursuit of knowledge and alternatives to promote sustainable development without compromising the environment. In recent years there has been a marked growth in the development of reinforced composite fiber plants, as an alternative for economic and ecological effects, especially in the substitution of synthetic materials such as reinforcement material in composites. In this current study the chemical- physical or (thermophysics )characteristics of the babassu coconut fiber, derived from the epicarp of the fruit (Orbignyda Phalerata), which the main constituents of the fiber: Klason lignin, insoluble, cellulose, holocellulose, hemicellulose and the content of ash and moisture will be determined. A study was conducted about the superficial modification of the fibers of the epicarp babassu coconut under the influence of chemical treatment by alkalinization, in an aqueous solution of NaOH to 2.5% (m/v) and to 5.0% to improve the compatibility matrix / reinforcement composite with epoxy matrix. The results of the changes occurred in staple fibers through the use of the techniques of thermogravimetric analyses (TG) and differential scanning calorimetry (DSC). The results found on thermal analysis on samples of fiber without chemical treatment (alkalinities), and on fiber samples treated by alkalinization show that the proposed chemical treatment increases the thermal stability of the fibers and provides a growth of the surface of area fibers, parameters that enhance adhesion fiber / composite. The findings were evaluated and compared with published results from other vegetable fibers, showing that the use of babassu coconut fibers has technical and economic potential for its use as reinforcement in composites / Atualmente as quest?es ambientais ganham destaque cada vez mais acentuado, j? que o futuro da humanidade est? dependente das a??es tomadas hoje pelo homem. Grandes esfor?os est?o sendo despendidos na busca de conhecimentos e solu??es alternativas sustent?veis que promova o desenvolvimento sem comprometimento do meio ambiente. Nos ?ltimos anos tem havido um crescimento acentuado no desenvolvimento de comp?sitos refor?ados por fibras vegetais, como uma alternativa econ?mica e ecol?gica, principalmente, na substitui??o de materiais sint?ticos, como material de refor?o em comp?sitos. No presente trabalho foram analisadas as caracter?sticas qu?mico-f?sicas de fibra oriundas do epicarpo do coco baba?u (Orbignyda Phalerata), sendo determinados os principais teores dos constituintes da fibra: lignina Klason insol?vel, celulose, holocelulose, hemicelulose e os teores de cinzas e de umidade. Foi realizado um estudo da modifica??o superficial das fibras do epicarpo do coco baba?u sob efeito de tratamento qu?mico por alcaliniza??o, em solu??o aquosa de NaOH a 2,5% (m/v) e a 5,0% (m/v), visando melhorar a compatibiliza??o matriz/refor?o em comp?sito com a matriz de ep?xi. Os resultados das modifica??es ocorridas nas fibras foram estudados atrav?s de t?cnicas de termogravimetria (TG) e de calorimetria explorat?ria diferencial (DSC). Os resultados encontrados nas an?lises t?rmicas em amostras de fibras sem tratamento qu?mico e em amostras de fibras tratadas por alcaliniza??o mostram que o tratamento qu?mico proposto aumentou a estabilidade t?rmica das fibras e proporcionou um crescimento na ?rea superficial das fibras, par?metros que melhoram a ades?o fibra/comp?sito. Os resultados obtidos foram avaliados e comparados com resultados publicados de outras fibras vegetais, mostrando que a utiliza??o das fibras de coco baba?u tem potencialidades t?cnicas e econ?micas para o seu uso como refor?o de comp?sitos