Made available in DSpace on 2014-12-17T15:42:03Z (GMT). No. of bitstreams: 1 EwertonRFT_DISSERT.pdf: 4228292 bytes, checksum: 8fb23445cdaa1e3bfe9b7d317ec439df (MD5) Previous issue date: 2012-10-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims to study the influence of two additives, the monomer, acrylamide and its polymer, polyacrylamide, solubilized in microemulsion systems and applied on enhanced oil recovery. By the microemulsion system obtained, it was chosen points into the phase diagram, presenting these compositions: 25%, 30%, 35% C/T; 2% Fo (fixed for all points) e 73%, 68% e 63% Fa, respectively. However, the monomer and the polymer were solubilized in these microemulsion points with 0.1%; 0.5%; 1% e 2% of concentration, ordering to check the concentration influence at the physicochemical properties (surface tension and rheology) of the microemulsion. Through the salinity study, was possible to observe that the concentrations of 1% and 2% of polymer made the solution became blurred, accordingly, the study of surface tension and rheology only was made for the concentrations of 0.1% e 0.5% of monomer and polymer, respectively. By the surface tension study it was observed that how the concentration of active matter (C/T) was increasing the surface tension was amending for each system, with or without additives. In the rheology study, as it increases the concentration of active matter increases both the viscosity of the microemulsion system (SME) with no additive, as the SME with polymer (AD2). After the entire study, it was chosen the lower point of active matter (25% C/T; 2% Fo e 73% Fa), plus additives in concentrations of 0.1% and 0.5% to be used on enhanced oil recovery. Assays were made on sandstone from Botucatu Formation, where after the tests, it was concluded that among the studied points, the point who showed the best efficiency of advanced shift was the microemulsion system + 0.5% AD2, with a recovery of 28% of oil in place and a total of 96,49%, while the other solution with 0.5% of polymer presented the worst result, with 14.1% of oil in place and 67,39% of efficiency of total displacement / Este trabalho tem como objetivo estudar a influ?ncia de dois aditivos, a acrilamida e seu pol?mero, poliacrilamida, solubilizados em sistemas microemulsionados e aplicados na recupera??o avan?ada de petr?leo. Atrav?s da obten??o do sistema microemulsionado, foram escolhidos pontos do diagrama de fases apresentando as seguintes composi??es: 25%, 30%, 35% C/T; 2% Fo (fixa para todos os pontos) e 73%, 68% e 63% Fa, respectivamente. O mon?mero e o pol?mero foram solubilizados nestes pontos de microemuls?o nas concentra??es de 0,1%; 0,5%; 1% e 2%, visando verificar a influ?ncia da concentra??o nas propriedades f?sico-qu?micas (tens?o superficial e reologia) da microemuls?o. Atrav?s do estudo de salinidade, foi poss?vel observar que as concentra??es 1% e 2% de pol?mero turvaram a microemuls?o, portanto, o estudo de tens?o e reologia foi realizado para as concentra??es 0,1% e 0,5% de mon?mero e pol?mero, respectivamente. Atrav?s do estudo de tens?o superficial observou-se que ? medida que aumenta a concentra??o de mat?ria ativa (C/T) altera a tens?o superficial para ambos sistemas com e sem aditivos. No estudo de reologia, ? medida que aumenta a concentra??o de mat?ria ativa, aumenta tanto a viscosidade do sistema microemulsionado (SME) sem aditivo, quanto o SME com pol?mero (AD2). Ap?s esse estudo, foi selecionado o ponto de menor concentra??o de mat?ria ativa (25% C/T; 2% Fo e 73% Fa) acrescido dos aditivos nas concentra??es 0,1% e 0,5% para serem utilizados na recupera??o avan?ada de petr?leo. Os ensaios foram realizados em arenitos da forma??o Botucatu, onde, ap?s terem sido realizados os testes, concluiu-se que dentre os pontos estudados, o que apresentou a melhor efici?ncia de deslocamento avan?ada foi o sistema microemulsionado + 0,5% de poliacrilamida (AD2), com uma recupera??o de 28% de ?leo in place e total de 96,49%, que ao ser comparada a solu??o de 0,5% do mesmo pol?mero apresentou recupera??o avan?ada de 14,1% de ?leo in place e 67,39% de efici?ncia de deslocamento total. A realiza??o deste trabalho mostrou que a utiliza??o de pol?meros em sistemas microemulsionado aparece como uma alternativa vi?vel na recupera??o avan?ada de petr?leo

Made available in DSpace on 2014-12-17T15:42:14Z (GMT). No. of bitstreams: 1 RosemiroMB_DISSERT.pdf: 2340991 bytes, checksum: c71ab28274a335ce511c0a85fd6c1157 (MD5) Previous issue date: 2014-01-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The knowledge of the rheological behavior of microemulsionated systems (SME) is of fundamental importance due to the diversity of industrial applications of these systems. This dissertation presents the rheological behavior of the microemulsionated system formed by RNX 95/alcohol isopropyl/p-toulen sodium sulfonate/kerosene/distilled water with the addition of polyacrylamide polymer. It was chosen three polymers of the polyacrylamide type, which differ in molar weight and charge density. It was studied the addition of these polymers in relatively small concentration 0,1% in mass and maximum concentration of 2,0%. It was made analysis of flow to determine the appearing viscosities of the SME and rheological parameters applying Bingham, Ostwald de Waale and Herschell-Buckley models. The behavior into saline environment of this system was studied for a solution of KCl 2,0%, replacing the distilled water. It was determined the behavior of microemulsions in relation with the temperature through curves of flow in temperatures of 25 to 60?C in variations of 5?C. After the analysis of the results the microemulsion without the addition of polymer presented a slight increase in its viscosity, but it does not mischaracterize it as a Newtonian fluid. However the additive systems when analyzed with low concentration of polymer adjusted well to the applied models, with a very close behavior of microemulsion. The higher concentration of the polymer gave the systems a behavior of plastic fluid. The results of the temperature variation point to an increase of viscosity in the systems that can be related to structural changes in the micelles formed in the own microemulsion without the addition of polymer / O conhecimento do comportamento reol?gico de sistemas microemulsionados (SME) ? de fundamental import?ncia, devido ? diversidade de aplica??es industriais desses sistemas. Esse trabalho apresenta o comportamento reol?gico do sistema microemulsionado formado por RNX 95/?lcool isoprop?lico/p-tolueno sulfonato de s?dio/Querosene/?gua destilada com a adi??o do pol?mero poliacrilamida. Foram escolhidos tr?s pol?meros do tipo poliacrilamida, que diferem quanto a massa molar e sua densidade de carga. Estudou-se a adi??o desses pol?meros em concentra??o relativamente baixa 0,1% em massa e concentra??o m?xima de 2,0%. Foram realizadas an?lises de escoamento para a determina??o das viscosidades aparente dos SME e par?metros reol?gicos aplicando os modelos de Bingham, Ostwald de Waale e Herschell-Buckley. O comportamento em meio salino desse sistema foi estudado para uma solu??o de KCl 2,0%, em substitui??o ? ?gua destilada. Foi determinado o comportamento das microemuls?es em rela??o ? temperatura atrav?s de curvas de escoamento a temperaturas de 25 a 60?C com varia??es de 5?C. Ap?s an?lise dos resultados a microemuls?o sem adi??o de pol?mero apresentou um ligeiro aumento em sua viscosidade, mas o que n?o a descaracteriza como um fluido newtoniano. Os sistemas aditivados quando analisados com concentra??o baixa de pol?mero ajustaram-se bem aos modelos aplicados, com comportamento muito pr?ximo da microemuls?o. J? a concentra??o mais elevada de pol?mero deu aos sistemas comportamento de fluido pl?stico. Os resultados da varia??o de temperatura apontam para um aumento na viscosidade dos sistemas que pode estar relacionado a mudan?as estruturais nas micelas formadas na pr?pria microemuls?o sem adi??o de pol?mero

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T21:36:56Z No. of bitstreams: 1 YanneKatiussyPereiraGurgelAum_TESE.pdf: 6627186 bytes, checksum: d33803d10b325c75e88616c3f67addc1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-15T00:29:35Z (GMT) No. of bitstreams: 1 YanneKatiussyPereiraGurgelAum_TESE.pdf: 6627186 bytes, checksum: d33803d10b325c75e88616c3f67addc1 (MD5) / Made available in DSpace on 2016-10-15T00:29:35Z (GMT). No. of bitstreams: 1 YanneKatiussyPereiraGurgelAum_TESE.pdf: 6627186 bytes, checksum: d33803d10b325c75e88616c3f67addc1 (MD5) Previous issue date: 2016-05-23 / A deposi??o de parafinas ? um problema cr?tico na ind?stria do petr?leo, pois pode influenciar de maneira crucial as opera??es de produ??o e transporte. Apesar da diversidade de t?cnicas de remedia??o, as utilizadas atualmente apresentam problemas e limita??es na sua aplica??o devido aos mais diversos cen?rios encontrados. As microemuls?es apresentam elevado potencial de solubiliza??o, entretanto h? uma escassez de trabalhos voltados para a sua aplica??o na remo??o de parafinas. Portanto, este trabalho teve como objetivo desenvolver sistemas microemulsionados (ME) ?leo em ?gua (O/A) visando a remo??o de dep?sitos paraf?nicos. V?rias formula??es para quatro diferentes sistemas microemulsionados O/A foram avaliadas. Esses sistemas foram constitu?dos por: ALK-L90, como tensoativo; n-butanol, como co-tensoativo; ?gua destilada; e como fase ?leo, quatro diferentes solventes, querosene, xileno, diesel e a mistura querosene-xileno. Os sistemas foram caracterizados quanto ao equil?brio de fases, tamanho de part?cula, tens?o superficial e reologia. Estudos de molhabilidade da superf?cie paraf?nica a esses sistemas e do comportamento reol?gico dos sistemas ME contendo parafina, submetidos ? diferentes temperaturas, foram realizados com a finalidade de avaliar a intera??o fluido-parafina. Uma metodologia para avaliar a efici?ncia de remo??o de parafinas em dutos foi desenvolvida e empregada na avalia??o do desempenho dos sistemas propostos. Os resultados mostraram que os componentes qu?micos utilizados favoreceram a forma??o de microemuls?es O/A, do tipo Winsor IV. Os ensaios de molhabilidade confirmaram a elevada capacidade de intera??o entre os sistemas ME obtidos e a parafina. Sistemas ME com parafina apresentam comportamentos bighamiano e newtoniano, com boa capacidade de bombeamento devido aos baixos valores de viscosidade e de tens?o inicial de escoamento. A efici?ncia de remo??o (ER) dos sistemas ME O/A foi compar?vel e, em alguns casos, superior ? dos solventes puros, apesar do elevado percentual de ?gua. A modelagem e an?lise estat?stica dos dados experimentais de remo??o geraram modelos capazes de descrever e estimar a ER em fun??o da composi??o do sistema ME, bem como entender o seu mecanismo de atua??o. Portanto, os sistemas ME O/A propostos apresentam-se como uma alternativa concreta na remo??o de dep?sitos paraf?nicos, com menor risco ambiental e inflamabilidade que os sistemas convencionais utilizados na ind?stria. / Paraffin deposition is a critical issue in the petroleum industry, since it can crucially affect both transport and production operations. In spite of the diversity of remediation techniques, those currently used may present problems and limitations when applied, due to the great number of different scenarios that can be found. Even though the microemulsions display a high potential for solubilization, the studies related to their application in paraffin removal are very scarce. Thus, this work aimed to develop oil-in-water (O/W) microemulsion systems (ME) with high capacity of removing paraffin deposits. Several formulations of four different O/W microemulsion systems were evaluated. The aforementioned systems were composed by: ALK-L90 as surfactant; butan-1-ol as cosurfactant; distilled water; and as oil phase, four different components (kerosene, xylene, diesel and a kerosene-xylene mixture). The systems were characterized regarding phase equilibrium, particle size, surface tension and rheology. Paraffin surface wettability studies related to these systems, as well as studies on the rheological behaviour of each of the ME systems containing paraffin, under different temperatures, were performed aiming to assess the fluid-paraffin interaction. A methodology to evaluate the efficiency of paraffin removal in pipelines was developed and applied for the performance evaluation of each of the proposed systems. The results demonstrated that the chemicals used favoured the formation of Winsor-IV O/W microemulsions. The wettability studies confirmed the high interaction capacity between the ME systems and the paraffin surface. Also, the ME systems with paraffin presented Binghamian and Newtonian behaviors, with a great pumping capacity due to the low values of viscosity and initial flow tension. The removal efficiencies of the O/W ME systems were similar to and, in some cases, even higher than the efficiencies of pure solvents, despite the high water percentage. The statistical analysis and modelling of the experimental data generated models there are able to both describe and estimate the removal efficiency as a function of the ME system composition, as well as to understand its action mechanism. Therefore, the proposed O/W ME systems present a valid alternative in the removal of paraffin deposits, with lower environmental risks and inflammability than the conventional systems used in the industry.

Made available in DSpace on 2014-12-17T14:08:49Z (GMT). No. of bitstreams: 1 IgorAAS_DISSERT.pdf: 5145970 bytes, checksum: b6f39625d81ac61de218f76a5802ba1e (MD5) Previous issue date: 2012-01-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The program PROBIODIESEL from the Ministry of Science and Technology has substantially increased glycerine, obtained as a sub-product of biodiesel production process, making it necessary to seek alternatives for the use of this co-product. On the other hand, herbicides although play a role of fundamental importance in the agricultural production system in force, have been under growing concern among the various segments of society because of their potential environmental risk. In this work, we used glycerin in microemulsion systems for application of herbicides, to improve efficiency and lower environmental pollution caused by the loss of those products to the environment. To obtain the systems of microemulsinados were used Unitol L90 NP and Renex 40 as surfactants, butanol as co-surfactant, coconut oil as oil phase and aqueous phase as we used solutions of glycerin + water. Through the determination of phase diagrams, the microemulsion region was found in the system E (L90 Unitol, coconut oil and glycerin + water 1:1). Three points were chosen to the aqueous phase rich in characterization and application in the solubilization of glyphosate and atrazine. Three experiments were performed in Horta, Department of Plant Sciences, Plant Science Sector, UFERSA, Mossor?-RN. The first experiment was conducted in randomized complete blocks with 20 treatments and four replications. The treatments consisted of five doses of the herbicide glyphosate (0.0, 0.45, 0.9, 1.35 and 1.8 L ha-1) diluted with four sauces: C1, C2, C3 (microemulsions) and C4 (water). The phytotoxicity of Brachiaria brizantha was measured at 7, 14, 28 and 60 DAA (days after application). At 60 DAA, we evaluated the biomass of plants. The second experiment was developed in randomized complete blocks with 20 treatments and four repetitions. The treatments consisted of five doses of the herbicide atrazine (0.0, 0.4, 0.8, 1.6 and 2.4 L ha-1) diluted with four sauces: C1, C2, C3 (microemulsions) and C4 (water). The phytotoxicity on Zea mays and Talinum paniculatum was evaluated at 2, 7, 20 DAA. The experiment III was developed in randomized complete blocks with 16 treatments and three repetitions. The treatments consisted of 16 combinations among the constituents of the microemulsion: Unitol L90 surfactant (0.0, 1.66, 5.0, 15 %) and glycerin (0.0, 4.44, 13.33 and 40.0 %). The phytotoxicity on Zea mays was evaluated at 1, 7 and 14 DAA. At 14 DAA, we evaluated the biomass of plants. The control plants using the microemulsions was lower than in the water due to the poisoning caused by the initial microemulsions in the leaves of the plants, a fact that hinders the absorption and translocation of the herbicide. There was no toxicity in Zea mays plants caused by the herbicide, however, were highly intoxicated by microemulsions. T. paniculatum was better controlled in spraying with the microemulsions, regardless of the dose of the herbicide. The glycerine did not cause plant damage. Higher poisoning the plants are caused by tensoactive Unitol L90 and higher rates occur with the use of higher concentrations of surfactant and glycerin, or microemulsion. The microemulsions used hampered the action of glyphosate in controlling B. brizantha and caused severe poisoning in corn, and these poisonings attributed mainly to the action of surfactant / O programa PROBIODIESEL do Minist?rio da Ci?ncia e Tecnologia aumentou consideravelmente a oferta de glicerina, obtida como sub-produto no processo de produ??o do biodiesel, tornando-se necess?rio a busca de alternativas econ?micas e ambientalmente corretas para a utiliza??o deste co-produto. Por outro lado, os herbicidas, embora desempenhem papel de fundamental import?ncia no sistema de produ??o agr?cola vigente, t?m sido alvo de crescente preocupa??o por parte dos diversos segmentos da sociedade, em virtude de seu potencial de risco ambiental. Neste trabalho, empregou-se a glicerina em sistemas microemulsionados para a aplica??o na pulveriza??o com herbicidas, visando melhor efici?ncia e menor contamina??o ambiental provocada pelas perdas desses produtos para o meio ambiente. Para obten??o dos sistemas microemulsinados foram utilizados Unitol L90 e Renex NP 40 como tensoativos, butanol como co-tensoativo, ?leo de coco como fase ?leo e como fase aquosa utilizou-se solu??es de glicerina + ?gua. Atrav?s da determina??o dos diagramas de fases, a regi?o de microemuls?o foi encontrada no sistema E (Unitol L90, ?leo de coco e glicerina + ?gua 1:1). Escolheu-se tr?s pontos ricos em fase aquosa para caracteriza??o e aplica??o na pulveriza??o com os herbicidas glyphosate e atrazine. Foram realizados tr?s experimentos na Horta do Departamento de Ci?ncias Vegetais, setor Fitotecnia, UFERSA, Mossor?-RN. O experimento I foi desenvolvido em blocos casualizados completos com 20 tratamentos e quatro repeti??es. Os tratamentos consistiram de cinco doses do herbicida glyphosate (0,00; 0,45; 0,90; 1,35 e 1,80 L ha-1) dilu?dos em quatro caldas: Calda 1, Calda 2, Calda 3 (microemuls?es) e Calda 4 (?gua). A fitotoxicidade sobre B. brizantha foi avaliada aos 7, 14, 28 e 60 DAA (dias ap?s aplica??o). Aos 60 DAA, avaliou-se a biomassa seca das plantas. O experimento II foi desenvolvido em blocos casualizados completos com 20 tratamentos e quatro repeti??es. Os tratamentos consistiram de cinco doses do herbicida atrazine (0,0; 0,4; 0,8; 1,6 e 2,4 L ha-1) dilu?dos em quatro caldas: Calda 1, Calda 2, Calda 3 (microemuls?es) e Calda 4 (?gua). A fitotoxicidade sobre Zea mays e Talinum paniculatum foi avaliada aos 2, 7, 20 DAA. O experimento III foi desenvolvido em blocos casualizados completos com 16 tratamentos e tr?s repeti??es. Os tratamentos consistiram 16 combina??es entre os constituintes da microemuls?o: Tensoativo Unitol L90 (0,0; 1,66; 5,0 e 15 %) e Glicerina (0,0; 4,44; 13,33 e 40,0 %). A fitotoxicidade sobre Zea mays foi avaliada aos 1, 7 e 14 DAA. Aos 14 DAA, avaliou-se a biomassa seca das plantas. O controle de plantas usando as microemuls?es foi inferior ao da ?gua devido a intoxica??o inicial causada pelas microemuls?es nas folhas das plantas, fato que dificultou a absor??o e transloca??o do herbicida. N?o houve intoxica??o nas plantas de Zea mays causadas pelo herbicida, por?m, foram altamente intoxicadas pelas microemuls?es. O T. paniculatum foi melhor controlado nas pulveriza??es com as microemuls?es, independente da dose do herbicida. A glicerina n?o provocou danos ?s plantas. Maiores intoxica??es nas plantas s?o causadas pelo tensoativo Unitol L90 e ?ndices mais elevados ocorrem com o uso de maiores concentra??es do tensoativo e da glicerina, ou seja, microemuls?o. As microemuls?es utilizadas prejudicaram a a??o do glyphosate no controle da B. brizantha e causaram severas intoxica??es na cultura do milho, sendo estas intoxica??es atribu?das principalmente ? a??o do tensoativo

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-09-21T19:00:02Z No. of bitstreams: 1 KalineArrudaDeOliveiraSantos_TESE.pdf: 5463841 bytes, checksum: bef807ab79b5e2fe855d0d682dec9605 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2015-09-24T12:53:23Z (GMT) No. of bitstreams: 1 KalineArrudaDeOliveiraSantos_TESE.pdf: 5463841 bytes, checksum: bef807ab79b5e2fe855d0d682dec9605 (MD5) / Made available in DSpace on 2015-09-24T12:53:23Z (GMT). No. of bitstreams: 1 KalineArrudaDeOliveiraSantos_TESE.pdf: 5463841 bytes, checksum: bef807ab79b5e2fe855d0d682dec9605 (MD5) Previous issue date: 2014-02-27 / Surfactants are versatile organic compounds that have, in a single molecule, double chemical affinity. The surfactant molecule is composed by a hy drophobic tail group, a hydrocarbon chain (linear, branched, or mixed), and by a hydrophilic head group, which contains polar groups that makes it able to be applied in the organophilization process of natural clays. Microemulsions are microheterogeneous b lends composed by: a surfactant, an oily phase (non - polar solvent), an aqueous phase, and, sometimes, a co - surfactant (short - chain alcohol). They are systems with thermodynamic stability, transparent, and have high solubility power. Vermiculite is a clay m ineral with an expandable crystalline structure that has high cation exchange capacity. In this work vermiculite was used to obtain organoclays. The ionic surfactants dodecyl ammonium chlori de (DDAC) and cetyltrimethylammonium bromide (C 16 TAB) were used in the organophilization process. They were used as surfactant aqueous solutions and, for DDAC, as a microemulsion system. The organoclays were used to promote the separation of binary mixtures of xylene isomers (ortho - and meta - xylene). Dif ferent analytical techniques were used to characterize microemulsion systems and also the nanoclays. It was produced a water - rich microemulsion system with 0.92 nm droplet average diameter. The vermiculite used in this work has a cationic exchange capacity of 172 meq/100g and magnesium as main cation (24.25%). The basal spacing of natural vermiculite and organo - vermiculites were obtained by X - ray Diffraction technique. The basal spacing was 1.48nm for natural vermiculite, 4.01nm for CTAB - vermiculite (CTAB 4 ) , and 3.03nm for DDAC - vermiculite (DDAC M1A), that proves the intercalation process. Separation tests were carried out in glass columns using three binary mixtures of xylene (ortho - xylene and meta - xylene). The results showed that the organovermiculite pre sented an enhanced chemical affinity by the mixture of hydrocarbons, when compared with the natural vermiculite, and also its preference by ortho - xylene. A factorial experimental design 2 2 with triplicate at the central point was used to optimize the xylen e separation process. The experimental design revealed that the initial concentration of isomers in the mixture and the mass of organovermiculite were the significant factors for an improved separation of isomers. In the experiments carried out using a bin ary mixture of ortho - xylene and meta - xylene (2:1), after its percolating through the organovermiculite bed (DDAC M1), it was observed the preference of the organoclay by the ortho - xylene isomer, which was retained in greater quantity than the meta - xylene o ne. At the end of the treatment, it was obtained a final concentration in meta - xylene of 47.52%. / Os processos de separa??o s?o atividades bastante difundidas na ind?stria, principalmente na ind?stria qu?mica, e que sofrem frequentes mudan?as com o objetivo de melhorar o desempenho, o rendimento e a viabilidade desses processos de separa??o. Os is?meros do xileno s?o compostos derivados do petr?leo, cuja estrutura qu?mica ? formada por um ?nico anel benz?nico e dois grupos met?licos ligados ao anel em tr?s posi??es diferentes. Devido ?s suas importantes aplica??es industriais, em especial na ind?stria de pl?sticos, diversos estudos s?o desenvolvidos, voltados para a utiliza??o de novos materiais, com o objetivo de resolver antigos problemas e melhorar os processos de separa??o destes is?meros. Os tensoativos s?o compostos org?nicos vers?teis, por possu?rem em uma ?nica mol?cula, dupla afinidade qu?mica, ou seja uma parte da mol?cula ? formada por uma cadeia hidrocarb?nica (linear, ramificada ou mista) hidrof?bica, e a outra parte cont?m grupos polares e hidrof?licos e podem ser aplicados na organofiliza??o de argilas. A microemuls?o ? uma mistura microheterogenea constitu?da de tensoativo, ?leo (solvente apolar) e uma fase aquosa, ?s vezes na presen?a de um cotensoativo, ?lcool de cadeia curta, que apresenta estabilidade termodin?mica, transparente e com alto poder de solubiliza??o. A vermiculita ? um argilomineral com elevada capacidade de troca de c?tion e estrutura cristalina expans?vel. Neste trabalho foram produzidas organovermiculitas com os tensoativos i?nicos cloreto de dodecilam?mio (DDAC) e brometo de cetiltrimetilamonio (C16TAB) a partir de solu??es de tensoativos, como tamb?m a partir de microemuls?o com o tensoativo DDAC, visando utiliz?-las para promover a separa??o de misturas bin?rias de is?meros do xileno (orto- e meta-xileno). Foram utilizadas diferentes t?cnicas anal?ticas para a caracteriza??o da microemuls?o utilizada e dos novos materiais produzidos. A microemuls?o utilizada ? rica em ?gua e possui di?metro m?dio de part?culas de 0,92 nm. A vermiculita utilizada possui uma capacidade de troca cati?nica de 172 meq/100g e na sua composi??o o c?tion majorit?rio o magn?sio (24,25%). A an?lise de TG comprovou que at? 220?C as organovermiculitas DDAC M1 possuem maior estabilidade t?rmica que a vermiculita s?dica. Atrav?s de DRX foi comprovado o aumento no espa?o basal de 1,48 nm para 3,59 nm (valor m?ximo obtido). Os ensaios de separa??o, foram realizados em colunas de vidro e utilizadas tr?s misturas bin?rias de xileno (orto-xileno e meta-xileno). Os resultados comprovaram um aumento da afinidade qu?mica da organovermiculita com a mistura de hidrocarbonetos e a sua prefer?ncia pelo orto-xileno. Com o objetivo de otimizar os ensaios de separa??o foi realizado dois planejamentos fatoriais 22 com triplicata no ponto central. Os resultados comprovaram que para a separa??o dos is?meros a concentra??o da mistura inicial dos is?meros e a massa de organovermiculita utilizada s?o par?metros significativos para uma boa separa??o. Utilizando uma mistura inicial com 66,6% de orto-xileno e 33,3% de meta-xileno ap?s o contado com a organovermiculita (DDAC M1) foi obtida fra??o, cuja concentra??o foi de 57,52% em meta-xileno.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-01T21:27:07Z No. of bitstreams: 1 EmilyCintiaTossiDeAraujoCosta_TESE.pdf: 2216846 bytes, checksum: 5f38e382d8ae3c1bfe9f3db58b62a672 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2016-02-02T21:24:40Z (GMT) No. of bitstreams: 1 EmilyCintiaTossiDeAraujoCosta_TESE.pdf: 2216846 bytes, checksum: 5f38e382d8ae3c1bfe9f3db58b62a672 (MD5) / Made available in DSpace on 2016-02-02T21:24:40Z (GMT). No. of bitstreams: 1 EmilyCintiaTossiDeAraujoCosta_TESE.pdf: 2216846 bytes, checksum: 5f38e382d8ae3c1bfe9f3db58b62a672 (MD5) Previous issue date: 2013-09-23 / A contamina??o de ?guas naturais por metais tornou-se assunto de interesse p?blico mundial por serem considerados biocumulativos. A determina??o e o monitoramento de contaminantes met?licos em ?guas ? uma tarefa que deve ser cont?nua e por isto a import?ncia do desenvolvimento, modifica??o e otimiza??o de metodologias anal?ticas capazes de realizar a determina??o dos v?rios contaminantes met?licos em ambientes naturais, pois em muitos casos, a instrumenta??o dispon?vel n?o apresenta sensibilidade anal?tica suficiente para a determina??o de tra?os. Neste estudo, um m?todo de extra??o e pr?-concentra??o utilizando um sistema microemulsionado, no equil?brio de Winsor II foi testado e otimizado para a determina??o dos metais Co, Cd, Pb, Tl, Cu e Ni por Espectrometria de absor??o at?mica de alta resolu??o com fonte cont?nua e atomiza??o em forno de grafite e chama (HR-CS AAS). A otimiza??o do programa de temperatura para o forno de grafite foi realizada atrav?s de curvas de pir?lise e atomiza??o para cada analito sem e com o uso de diferentes modificadores qu?micos. Cd e Pb tiveram condi??es ?timas com modificador permanente Ru, pir?lise em 700?C e atomiza??o em 1700?C, para Tl solu??o Pd/Mg foi o melhor modificador, temperaturas 600?C e 1700?C de pir?lise e atomiza??o, respectivamente e para o Co pir?lise em 800?C e atomiza??o ? 2400?C sem uso de modificador qu?mico, por?m W foi empregado como modificador permanente a fim de se prolongar o tempo de vida ?til do forno. Cu e Ni foram analisados na chama ap?s pr?-concentra??o. Avaliou-se tamb?m fatores que influenciam a efici?ncia de extra??o, atrav?s do efeito salting out. Como compromisso, 6 g L-1 de Na e 1% de HNO3 (v/v) foi definido. Para determina??o do ponto ?timo de extra??o, um planejamento centroide-simplex foi aplicado, sendo escolhido como compromisso as seguintes propor??es: 70% fase aquosa, 10% fase ?leo e 20% Cotensoativo/Tensoativo (C/T = 4). Ap?s extra??o, os metais foram determinados e as Figuras de m?rito obtidas para o m?todo proposto foi: 0,1 a 10 ?g L-1 de faixa linear, LOD 0,094, 0,011, 0,057 e 0,050 ?g L-1 para Pb, Cd, Tl e Co, respectivamente. Testes de adi??o e recupera??o na amostra certificada apresentaram valores de recupera??o ap?s extra??o de 105 e 101% para Pb e Cd, respectivamente, e nas amostras fortificadas a recupera??o para os analitos ficou entre 107 e 108% comprovando que o m?todo proposto pode ser utilizado na extra??o, possibilitou a separa??o dos metais de matrizes complexas, e ainda com bom fator de pr?-concentra??o. / The determination and monitoring of metallic contaminants in water is a task that must be continuous, leading to the importance of the development, modification and optimization of analytical methodologies capab le of determining the various metal contaminants in natural environments, because, in many cases, the ava ilable instrumentation does not provide enough sensibility for the determination of trace values . In this study, a method of extraction and pre- concentration using a microemulsion system with in the Winsor II equilibrium was tested and optimized for the determination of Co, Cd, P b, Tl, Cu and Ni through the technique of high- resolution atomic absorption spectrometry using a continuum source (HR-CS AAS). The optimization of the temperature program for the graphite furnace (HR-CS AAS GF) was performed through the pyrolysis and atomization curves for the analytes Cd, Pb, Co and Tl with and without the use of different chemical modifiers. Cu and Ni we re analyzed by flame atomization (HR-CS F AAS) after pre-concentr ation, having the sample introduction system optimized for the realization of discrete sampling. Salinity and pH levels were also analyzed as influencing factors in the efficiency of the extraction. As final numbers, 6 g L -1 of Na (as NaCl) and 1% of HNO 3 (v/v) were defined. For the determination of the optimum extraction point, a centroid-simplex statistical plan was a pplied, having chosen as the optimum points of extraction for all of the analytes, the follo wing proportions: 70% aqueous phase, 10% oil phase and 20% co-surfactant/surfactant (C/S = 4). After extraction, the metals were determined and the merit figures obtained for the proposed method were: LOD 0,09, 0,01, 0,06, 0,05, 0,6 and 1,5 ?g L -1 for Pb, Cd, Tl, Co, Cu and Ni, re spectively. Line ar ranges of ,1- 2,0 ?g L -1 for Pb, 0,01-2,0 ?g L -1 for Cd, 1,0 - 20 ?g L -1 for Tl, 0,1-5,0 ?g L -1 for Co, 2-200 ?g L -1 and for Cu e Ni 5-200 ?g L -1 were obtained. The enrichment factors obtained ranged between 6 and 19. Recovery testing with the certified sample show ed recovery values (n = 3, certified values) after extraction of 105 and 101, 100 and 104% for Pb, Cd, Cu and Ni respectively. Samples of sweet waters of lake Jiqui, saline water from Potengi river and water produced from the oil industry (PETROBRAS) were spiked and the recovery (n = 3) for the analytes were between 80 and 112% confirming th at the proposed method can be used in the extraction. The proposed method enabled the sepa ration of metals from complex matrices, and with good pre-concentration factor, consistent with the MPV (allowed limits) compared to CONAMA Resolution No. 357/2005 which regulat es the quality of fresh surface water, brackish and saline water in Brazil.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-22T22:11:08Z No. of bitstreams: 1 KatherineCarrilhoDeOliveira_DISSERT.pdf: 1497827 bytes, checksum: 3a0a5af3991269a1455355c5e4a9c14b (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-24T21:29:21Z (GMT) No. of bitstreams: 1 KatherineCarrilhoDeOliveira_DISSERT.pdf: 1497827 bytes, checksum: 3a0a5af3991269a1455355c5e4a9c14b (MD5) / Made available in DSpace on 2016-02-24T21:29:21Z (GMT). No. of bitstreams: 1 KatherineCarrilhoDeOliveira_DISSERT.pdf: 1497827 bytes, checksum: 3a0a5af3991269a1455355c5e4a9c14b (MD5) Previous issue date: 2015-02-04 / Atualmente o mercado exige derivados de petr?leo cada vez mais puros e, com isso, surge a necessidade de novos m?todos para obten??o desses produtos que sejam mais eficientes e economicamente vi?veis. Considerando a remo??o do enxofre do diesel, a maioria das refinarias utiliza o processo de hidrogena??o catal?tica, a hidrodessulfuriza??o. Esses processos s?o de elevado conte?do energ?tico e alto custo de produ??o, al?m de baixa efici?ncia na remo??o do enxofre a baixas concentra??es (abaixo de 500 ppm). A adsor??o apresenta-se como uma alternativa eficiente e economicamente vi?vel em rela??o ?s t?cnicas atualmente utilizadas. Com isso, o objetivo principal deste trabalho ? desenvolver e otimizar a obten??o de novos adsorventes a base de diatomita, modificados com microemuls?es de dois tensoativos n?o i?nicos, agregando efici?ncia ao material, visando a sua aplica??o na remo??o do enxofre presente no diesel comercial. Para a modifica??o da diatomita, variou-se: os pontos de microemuls?o para cada tensoativo (RNX 95 e UNTL 90), a fase aquosa da microemuls?o atrav?s da utiliza??o ou n?o de sais (CaCl2 e BaCl2) , o tempo de contato durante a modifica??o e a forma de contato. Foram realizadas an?lises de microscopia eletr?nica de varredura, difra??o de raios X, fluoresc?ncia de raios X, termogravimetria e adsor??o de N2 (BET) para a caracteriza??o dos novos materiais obtidos. No estudo da capacidade de adsor??o dos materiais obtidos, foi realizada uma modelagem estat?stica para avaliar a influ?ncia da concentra??o do sal na fase aquosa (20 ppm a 1500 ppm), da temperatura do banho finito (25 a 60?C) e da concentra??o de enxofre do diesel. Observou-se que a temperatura e a concentra??o de enxofre (300 a 1100 ppm) foram os par?metros mais significativos, no qual aumentando-se seus valores aumenta-se a capacidade da argila modificada de adsorver o enxofre presente no diesel. A capacidade de adsor??o aumentou de 0,43 mg/g para 1,34 mg/g com a otimiza??o do ponto de microemuls?o e com a adi??o de sais. / Currently the market requires increasingly pure oil derivatives and, with that, comes the need for new methods for obtaining those products that are more efficient and economically viable. Considering the removal of sulfur from diesel, most refineries uses catalytic hydrogenation process, the hydrodesulfurization. These processes needs high energy content and high cost of production and has low efficiency in removing sulfur at low concentrations (below 500 ppm). The adsorption presents itself as an efficient and economically viable alternative in relation to the techniques currently used. With that, the main purpose of this work is to develop and optimize the obtaining of new adsorbents based on diatomite, modified with two non ionic surfactants microemulsions, adding efficiency to the material, to its application on removal of sulfur present in commercial diesel. Analyses were undertaken of scanning electron microscopy (SEM), x-ray diffraction (XRD), x-ray fluorescence (XRF), thermogravimetry (TG) and N2 adsorption (BET) for characterization of new materials obtained. The variables used for diatomite modification were: microemulsion points for each surfactant (RNX 95 and UNTL 90), microemulsion aqueous phase through the use or non-use of salts (CaCl2 and BaCl2), the contact time during the modification and the contact form. The study of adsorption capacity of materials obtained was performed using a statistical modeling to evaluate the influence of salt concentration in the aqueous phase (20 ppm to 1500 ppm), finite bath temperature (25 to 60? C) and the concentration of sulphur in diesel. It was observed that the temperature and the concentration of sulphur (300 to 1100 ppm) were the most significant parameters, in which increasing their values increase the ability of modified clay to adsorb the sulphur in diesel fuel. Adsorption capacity increased from 0.43 to mg/g 1.34 mg/g with microemulsion point optimization and with the addition of salts.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-09T23:31:45Z No. of bitstreams: 1 DanielNobreNunesDaSilva_DISSERT.pdf: 1373140 bytes, checksum: be843c5287aad6e511b26eef9e599382 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-11T23:38:54Z (GMT) No. of bitstreams: 1 DanielNobreNunesDaSilva_DISSERT.pdf: 1373140 bytes, checksum: be843c5287aad6e511b26eef9e599382 (MD5) / Made available in DSpace on 2016-03-11T23:38:54Z (GMT). No. of bitstreams: 1 DanielNobreNunesDaSilva_DISSERT.pdf: 1373140 bytes, checksum: be843c5287aad6e511b26eef9e599382 (MD5) Previous issue date: 2015-02-04 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / A ind?stria do petr?leo ? uma das atividades que mais gera res?duos ao meio ambiente. O cascalho de perfura??o ? um res?duo gerado em grande quantidade no processo de perfura??o de po?os e que pode provocar impactos ambientais, tais como a contamina??o do solo e consequentemente a contamina??o de len??is fre?ticos, caso descartados sem tratamento pr?vio. Surge ? necessidade de se desenvolver atividades cient?ficas e de pesquisar maneiras de adequar esses res?duos as normas ambientais vigentes. No caso dos res?duos s?lidos, a norma NBR 10004:2004 da Associa??o Brasileira de Normas T?cnicas (ABNT) classifica-os em res?duos classe I (perigoso) e classe II (n?o perigoso), onde estabelece quais os res?duos que podem ou n?o ser descartados no meio ambiente sem provocar impacto ambiental. Este trabalho apresenta uma inovadora alternativa para tratar o cascalho de perfura??o, que ? classificado como res?duo classe I (Abreu & Souza, 2005), removendo principalmente a n-parafina presente no mesmo, uma vez que este ? originado quando se usa fluidos de perfura??o base ?leo. Utilizando sistemas microemulsionados promove-se a remo??o deste contaminante de amostras de cascalho de perfura??o provenientes de po?os localizados em Alto do Rodrigues ? RN. Inicialmente, determinou-se a concentra??o de parafina utilizando o m?todo de infravermelho, em amostras previamente extra?das com ultrassom, obteve-se uma concentra??o de parafina na faixa de 36,59 a 43,52 g de parafina por quilograma de cascalho. Utilizou-se dois sistemas microemulsionados contendo dois tensoativos n?o i?nicos de diferentes classes, um ? um ?lcool etoxilado (UNTL-90) e o outro um nonifenol etoxilado (RNX 110). Os resultados indicaram que o sistema com tensoativo UNTL-90 possui melhor efici?ncia que o sistema com RNX 110. O estudo da influ?ncia do tempo de contato na extra??o mostrou que para tempos maiores que 25 minutos tem-se uma tend?ncia ao aumento do percentual de extra??o com o aumento do tempo de contato. Observou-se tamb?m que a extra??o ? r?pida, pois em 1 minutos de contato tem-se 22,7 % de extra??o. A reutiliza??o do sistema microemulsionado, sem a remo??o da parafina extra?da em etapas anteriores, mostrou redu??o de 29,32 no percentual de extra??o comparando a primeira e a terceira extra??o, mas comparando a primeira e segunda extra??es a redu??o ? de 8,5 no percentual de extra??o, logo a otimiza??o da reutiliza??o dos sistemas pode ser uma op??o para viabilizar economicamente a remo??o de parafina de cascalho. A extra??o com agita??o se mostrou mais eficaz no tratamento do cascalho, atingindo o percentual de extra??o de 87,04 %, ou seja, se obt?m um cascalho de perfura??o com 0,551 % de parafina. Utilizando o percentual de parafina empregado nos fluidos de perfura??o n?o aquosos e o limite m?ximo de fluido no cascalho para descarte estabelecido pela Ag?ncia de Prote??o Ambiental dos Estados Unidos (US Environmental Protection Agency - US EPA), chega-se ? conclus?o que o teor de parafina no cascalho n?o pode ser superior a 3,93 %. Conclui-se que a quantidade de parafina no cascalho tratado com o sistema microemulsionado e com agita??o est? bem abaixo do estabelecido pelo ?rg?o americano (US EPA), mostrando que o sistema microemulsionado utilizado foi eficiente na remo??o da parafina do cascalho de perfura??o. / The oil industry is one of the activities that generates more waste to the environment. The drill cuttings is a waste generated in large quantities in the drilling process and that may cause environmental damage such as soil contamination and consequently the contamination of groundwater if disposed of without prior treatment. Arises the need to develop scientific activities and research ways to adapt these wastes the current environmental standards. In the case of solid wastes, the NBR 10004: 2004 of the Brazilian Association of Technical Standards (ABNT) classifies them into class I waste (hazardous) and class II (not dangerous), which determines which wastes may or may not be discarded in the environment without causing environmental impact. This study presents a novel alternative for treating drill cuttings, where this waste was classified as class I (Abreu & Souza, 2005), mainly by removing the n-paraffin present in it, since this arises when using drilling fluids base oil. Using microemulsion systems promotes the removal of this contaminant drill cuttings samples from wells located in Alto do Rodrigues - RN. Initially, we determined the concentration of paraffin using infrared method in samples were extracted with ultrasound, we obtained a paraffin concentration in the range from 36.59 to 43.52 g of paraffin per kilogram of cuttings. Used two microemulsion systems containing two nonionic surfactants from different classes, one is an alcohol ethoxylated (UNTL-90) and the other an nonylphenol ethoxylated (RNX 110). The results indicated that the system UNTL-90 surfactant has better efficiency than the system with RNX 110. The study of the influence of contact time at the extraction showed that for times greater than 25 minutes has a tendency to increase the percentage extraction with increasing contact time. It was also observed that the extraction is fast because at 1 minute contact has 22.7% extraction. The reuse of the microemulsion system without removing the paraffin extracted in previous steps, showed reduction of 29.32 in percentage of extraction by comparing the first and third extraction, but by comparing the first and second extractions reduction is 8.5 in percentage extraction, so the systems reuse optimization can be an option for economically viable removing paraffin from cuttings. The extraction with shaking is more effective in the treatment of cuttings, reaching the extraction percentage of 87.04%, that is, obtaining a drill cuttings with 0.551% paraffin. Using the percentage of paraffin employed in non-aqueous drilling fluids and fluid maximum limit on cuttings for disposal established by the Environmental Protection Agency of the United States (US EPA), one arrives at the conclusion that the level of paraffin on gravel cannot exceed 3.93%. Conclude that the amount of paraffin in the treated cuttings with the microemulsion system with shaking is below the established by US EPA, showing that the system used was efficient in removing the paraffin from the drill cuttings.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-10T20:59:53Z No. of bitstreams: 1 GleidsonLimaPinheiro_DISSERT.pdf: 2590622 bytes, checksum: 06de3b4091ef1d22ceaba6df4aead4d0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-12T19:33:54Z (GMT) No. of bitstreams: 1 GleidsonLimaPinheiro_DISSERT.pdf: 2590622 bytes, checksum: 06de3b4091ef1d22ceaba6df4aead4d0 (MD5) / Made available in DSpace on 2016-05-12T19:33:54Z (GMT). No. of bitstreams: 1 GleidsonLimaPinheiro_DISSERT.pdf: 2590622 bytes, checksum: 06de3b4091ef1d22ceaba6df4aead4d0 (MD5) Previous issue date: 2014-08-15 / Oleodutos sofrem corros?o do tipo qu?mica, devido a tens?o, entre outros mecanismos, e eletroqu?mica devido a grande quantidade de salmoura (?gua e cloretos), presentes nos fluidos produzidos na forma??o. Este trabalho tem como objetivo estudar a efici?ncia de um inibidor de corros?o comercial, usado na ind?stria do petr?leo, na inibi??o de corros?o agindo isoladamente e em mistura com microemuls?o (ME) na propor??o [1:1]. A ME foi obtida a partir dos seguintes constituintes: ?gua de torneira (fase aquosa), querosene (fase oleosa), n-butanol (cotensoativo) e UNT L90 (tensoativo). O inibidor possui mecanismo de prote??o tipo f?lmico, na prote??o do a?o carbono API 5L A210, muito usado na constru??o de oleodutos terrestres. Os experimentos foram formulados em solu??es salinas com 3% de NaCl que funcionam como meio agressivo, na presen?a e aus?ncia de borbulhamento do g?s (CO2), em temperatura ambiente (25?C). O inibidor estudado apresenta em sua fase ativa compostos de am?nio quatern?rio e derivados de imidazolina, e foi caracterizado como um inibidor formador de filme. Os resultados de efici?ncia de inibi??o foram avaliados por dados experimentais de densidades de corrente de corros?o atrav?s da t?cnica eletroqu?mica polariza??o linear, com extrapola??o de Tafel. O inibidor comercial agindo isoladamente mostrou-se mais eficiente no combate ? corros?o do que em microemuls?o quando n?o houve borbulhamento de CO2. Quando ocorreu a satura??o da solu??o de trabalho com CO2, observou-se uma eleva??o da inibi??o ao misturar-se o aditivo comercial com a microemuls?o. Tamb?m se constatou que o excesso de CO2 dissolvido na solu??o de trabalho implicou em uma eleva??o da taxa de corros?o, comparado aos ensaios an?logos realizados na aus?ncia do borbulhamento cont?nuo de CO2. Os ensaios foram realizados em concentra??es de inibidores de 10, 20, 40, 100, 200 e 400 ppm. As melhores efici?ncias foram observadas nos ensaios com concentra??o de 40 ppm, na aus?ncia do borbulhamento, e 200 ppm, quando o ensaio foi realizado na presen?a de borbulhamento com CO2. Os dados experimentais se ajustaram ao modelo de Langmuir, sugerindo a forma??o de um filme de monocamadas. / Pipelines suffer from chemical, under tension, and other kinds of corrosion mechanisms, as well as electrochemica l corrosion caused by the existing large amount of brine (water and chlorides) in the produced fluids. The goal of this work is to research the efficiency of a commercial corrosion inhibitor, used in pipelines on the oil industry, on the corrosion inhibition of the API 5L A210 iron, which is widely used on the overland pipelines constructions, acting alone and in a mixture with micro emulsion (ME) on a [1:1] ratio. The ME was obtained from the following constituents: tap water (aqueous phase), kerosene (oily phase), n-butanol (co-surfactant), and UNT L90 (surfactant). We observed the formation of protective film on the steel surface as an inhibitor?s protection mechanism. The experiments were formulated in saline solutions with 3% of NaCl that functioned as aggressive environment, on the presence and absence of gas bubbling (CO2), in room temperature (25?C). The studied inhibitor exhibits in its active phase quaternary ammonium compounds and imidazoline derivatives, which means it is a film-forming inhibitor. The inhibition efficiency results are evaluated by experimental data of corrosion current density by the electrochemical technique of linear polarization with Talef extrapolation. The inhibitor exhibit two distinct behaviors: in medium of saturation with CO2 we observed an increase of inhibition by blending the commercial additive with the micro-emulsion, and in medium without saturation of CO2 we observed a higher efficiency when the inhibitor was acting singly. We also could find that the excess of dissolved CO2 in the working solution resulted in an increase of the corrosion rate, compared to similar experiments in the absence of continuous bubbling of CO2. The best efficiencies were observed in the experiments with concentration of 40ppm without bubbling, and 200ppm when the experiments were performed in the presence of bubbling with CO2. The experimental data fitted to the Langmuir model, suggesting the formation of a film made of monolayers.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-22T15:37:57Z No. of bitstreams: 1 PriscillaCibelleOliveiraDeSouzaFirmino_DISSERT.pdf: 2931554 bytes, checksum: 875d45632f3b9ed21653471af9188d59 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-27T23:33:06Z (GMT) No. of bitstreams: 1 PriscillaCibelleOliveiraDeSouzaFirmino_DISSERT.pdf: 2931554 bytes, checksum: 875d45632f3b9ed21653471af9188d59 (MD5) / Made available in DSpace on 2016-07-27T23:33:06Z (GMT). No. of bitstreams: 1 PriscillaCibelleOliveiraDeSouzaFirmino_DISSERT.pdf: 2931554 bytes, checksum: 875d45632f3b9ed21653471af9188d59 (MD5) Previous issue date: 2016-01-27 / Ag?ncia Nacional do Petr?leo - ANP / As rochas reservat?rio do tipo arenito s?o comumente respons?veis por acumula??es de petr?leo. A molhabilidade ? um par?metro fundamental para as propriedades f?sicas do reservat?rio, uma vez que interfere em caracter?sticas como a permeabilidade relativa ? fase aquosa, a distribui??o de ?leo residual no reservat?rio, as caracter?sticas de explora??o com inunda??es de ?gua e a recupera??o do petr?leo bruto. Este estudo consistiu em aplicar diferentes tipos de sistemas microemulsionados - SME - nos reservat?rios de arenito e avaliar as suas influ?ncias na molhabilidade e na recupera??o do petr?leo residual. Para tanto, foram obtidos quatro sistemas microemulsionados diferindo quanto ? natureza i?nica dos tensoativos (i?nicos e n?o i?nico). A caracteriza??o dos sistemas obtidos revelaram microemuls?es, que atrav?s de an?lises de tens?o superficial, massa espec?fica, di?metro de part?cula e viscosidade numa faixa de temperatura de 30 a 70?C foram caracterizadas. O petr?leo estudado foi caracterizado como do tipo leve e a rocha arenito ? proveniente da forma??o Botucatu. O estudo da influ?ncia dos sistemas microemulsionados na molhabilidade do arenito foi realizado atrav?s de medidas de ?ngulos de contato utilizando como par?metros o tempo de tratamento da rocha com SME e ap?s o contato salmoura-superficie, verificando o comportamento da varia??o de ?ngulo. Os resultados desse estudo mostraram que a rocha inicialmente de molhabilidade mista, para ap?s tratamento com os SME, teve sua molhabilidade invertida para molh?vel a ?gua. Em rela??o ao tempo de contato rocha-SME, foi evidenciado que a molhabilidade da rocha teve mais altera??o quando houve maior tempo de contanto entre sua superf?cie e os sistemas microemulsionados, como tamb?m que s? houve uma redu??o significativa para os primeiros 5 minutos de intera??o entre a superf?cie j? tratada e a salmoura. Os melhores resultados foram para o sistema microemulsionado ani?nico de tensoativo sintetizado, o cati?nico comercial, o ani?nico comercial e n?o i?nico, respectivamente. Para a atua??o dos sistemas na recupera??o avan?ada de petr?leo, todos apresentaram um percentual significativo de ?leo recuperado, com os melhores resultados para o sistema ani?nico, que atingiu a um percentual de 80% de recupera??o, comprovando os resultados do estudo da molhabilidade, que mostrou a influ?ncia desta propriedade sobre a intera??o entre os fluidos e a rocha reservat?rio e a capacidade dos sistemas microemulsionados para a recupera??o avan?ada de petr?leo em reservat?rios de arenito. / Sandstone-type reservoir rocks are commonly responsible for oil accumulation. The wettability is an important parameter for the physical properties of the container, since it interferes in characteristics such as relative permeability to the aqueous phase, residual oil distribution in the reservoir, operating characteristics with waterflood and recovery of crude oil. This study applied different types of microemulsion systems - MES - in sandstone reservoirs and evaluated their influences on wettability and residual oil recovery. For this purpose, four microemulsion were prepared by changing the nature of ionic surfactants (ionic and nonionic). Microemulsions could then be characterized by surface tension analysis, density, particle diameter and viscosity in the temperature range 30? C to 70? C. The studied oil was described as light and the sandstone rock was derived from the Botucatu formation. The study of the influence of microemulsion systems on sandstone wettability was performed by contact angle measurements using as parameters the rock treatment time with the MES and the time after the brine surface contact by checking the angle variation behavior. In the study results, the rock was initially wettable to oil and had its wettability changed to mixed wettability after treatment with MES, obtaining preference for water. Regarding rock-MES contact time, it was observed that the rock wettability changed more when the contact time between the surface and the microemulsion systems was longer. It was also noted only a significant reduction for the first 5 minutes of interaction between the treated surface and brine. The synthesized anionic surfactant, commercial cationic, commercial anionic and commercial nonionic microemulsion systems presented the best results, respectively. With regard to enhanced oil recovery performance, all systems showed a significant percentage of recovered oil, with the anionic systems presenting the best results. A percentage of 80% recovery was reached, confirming the wettability study results, which pointed the influence of this property on the interaction of fluids and reservoir rock, and the ability of microemulsion systems to perform enhanced oil recovery in sandstone reservoirs.