Avaliação de asfaltenos precipitados em diferentes condições de composição, temperatura e pressão

CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORAsphaltenes are a heavy fraction of petroleum with the ability for self-association, a phenomenon that can occur spontaneously in the reservoirs or in any of the various stages of production and processing, depending on variations in pressure, temperature412157162CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORsem informaçãoOs autores agradecem à CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior), pela bolsa de doutorado concedida a L. G. M. de Moura, e à PETROBRAS (Petróleo Brasileiro S. A.), pelas amostras de petróleo fornecidas para o desenvolvimento des

Fracionamento de proteinas e outros tensoativos em colunas de bolhas e espumas

Orientador: Cesar Costapinto Santana, Ruben G. CarbonellTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: o fracionamento com espuma foi utilizado para o enriquecimento e recuperação de soluções de albumina do soro bovino (BSA). A coluna de fracionamento foi operada em contínuo e em semi-batelada. Na operação contínua obteve-se enriquecimentos de 2 a 40 vezes e recuperações de 60 a 98%. Nestes experimentos foram investigados as influências da vazão e concentração de proteína na alimentação, da velocidade superficial do gás, das alturas das coluna de líquido e de espuma e da posição da alimentação sobre a eficiência do processo. O enriquecimento apresentou maiores valores para baixas concentrações e vazões de alimentação, não sendo muito sensível a variações da velocidade superficial do gás. A recuperação aumenta tanto com a diminuição da vazão de alimentação quanto com o aumento da velocidade superficial do gás. Na operação semi-batelada os valores médios do enriquecimento ficaram entre 1,3 e 3,1. A recuperação total de proteína variou de 73 a 90%. O enriquecimento aumentou com a diminuição da velocidade superficial do gás enquanto que a recuperação aumentou com a elevação dos valores da concentração inicial de proteína e da velocidade superficial do gás...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digitalAbstract: Foam ti'actionation ofproteins was studied using BSA as a model protein. The fractionation column was operated in semi-batch and continuous mode. Enrichment varied from 2 to 40 folds in the continuous operation and the protein recovery was in the range from 60 to 98%. The influence of feed flow rate, feed protein concentration, superficial gas velocity, liquid pool height, foam column height, and feed position on the process efficiency was evaluated. The enrichment increases decreasing either feed protein concentration or feed flow rate. The enrichment was almost constant with variations on superficial gas velocities. Enrichment values were between 1.3 and 3.1 and the total protein recovered was between 73 and 90 % in the semi-batch process. The enrichment increases decreasing the feed flow rate, while the total protein recovered increased either the superficial gas velocity or the initial protein concentration...Note: The complete abstract is available with the full electronic digital thesis or dissertationsDoutoradoEngenharia de ProcessosDoutor em Engenharia Químic

AVALIAÇÃO DE ASFALTENOS PRECIPITADOS EM DIFERENTES CONDIÇÕES DE COMPOSIÇÃO, TEMPERATURA E PRESSÃO

Asphaltenes are a heavy fraction of petroleum with the ability for self-association, a phenomenon that can occur spontaneously in the reservoirs or in any of the various stages of production and processing, depending on variations in pressure, temperature, composition and shearing, among others. In this work, it was evaluated the precipitation of asphaltenes in two oils (P01 and P02) in different conditions of temperature and pressure and in the absence or presence of CO2. Under high pressure and temperature conditions, the precipitation of asphaltenes was observed in the presence of CO2 in mixtures with methane, while the addition of propane induced precipitation in the absence of CO2. The results of analyses elemental (CHNO), SEM, FTIR and LDI-MS were consistent with the structure assigned to samples of this nature (oils, maltenes and fractions of asphaltenes insoluble in n-pentane, C5I, and n-heptane, C7I)

Evaluation of organic modification of montmorillonite with ionic and nonionic surfactants

This work aims at evaluating the organophilization of montmorillonite with two different types of surfactants: one ionic, containing C16-C18 di(alkyl ester) dimethyl ammonium chloride (EA) and one nonionic, containing ethoxylated tallow amine (ETA). Aqueous dispersion and semi-solid routes were compared in terms of functionalization efficiency by statistical analysis, and supercritical CO2 was performed as a complementary and comparative method. Besides, the effect of the washing process after functionalization was evaluated. X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) and contact angle were used to evaluate the intercalation of surfactants into montmorillonite and process yield. The d001-value was improved by both surfactants intercalation, and the conformations of the species inside the clay minerals were suggested. The final arrangement of the organic species into Mt was modified as a function of the concentration of surfactant added, and by the washing steps. Most process parameters evaluated showed significant effects on d001-value and process yield. The semi-solid method was confirmed as a good alternative route due to its efficiency and it could be an environmentally friendly option to be used. ETA-modified montmorillonites showed similar d001-values (around 4.0 nm) and higher thermal stability than EA-modified montmorillonite1502333CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQsem informaçã

Hybrid organo-montmorillonite produced by simultaneous intercalation of phosphonium and ammonium/amine based surfactants

This study describes the preparation and characterization of hybrid organo-modified montmorillonite (OMt) produced by intercalation of phosphonium-based plus ammonium and/or amine-based surfactants, aiming to improve thermal and compatibility properties for the manufacture of clay mineral polymer nanocomposites (CPN). The choice of the surfactants was based on previous studies, which have pointed out that the phosphonium-based surfactant provided the clay mineral a high thermal stability but low d001-value and hydrophobicity. On the other hand, ammonium-based compounds presented inverse properties, i.e., low thermal stability and high d001-value. The present work was supported by design of experiments (DOE) considering different surfactant concentrations. The materials were analyzed by thermogravimetric analysis (TGA) to evaluate the thermal stability and relative reactional yield, by X-ray diffraction (XRD), to evaluate the surfactant intercalation by d001 of the clay, also by Fourier-transform infrared spectroscopy (FTIR) and contact angle, to verify the components interaction and the hydrophobicity. The hybrid montmorillonites presented intermediate properties, as thermal stability and basal space, when compared with the clay modified by the single modifiers. The intercalated species were arranged in paraffin-type structure and their conformation and tilt angle changed by increasing the ammonium concentration. Statistical analysis allowed knowing the concentration effects of each surfactant on hybrid materials. From the statistical models, an optimized formulation considering the maximum d001-value, Tonset (initial temperature of thermal degradation) and yield responses was prepared, which had its significance tested by Anova and F-test, and was validated by experimental values218279288CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ142448/2013-

A comparative study of different routes for the modification of montmorillonite with ammonium and phosphonium salts

The objective of this work was to use a statistical tool to study and evaluate the main parameters in the preparation of organo-montmorillonite (O-Mt) by using different compounds and reactional routes (aqueous, semi-solid and supercritical CO2 medium) aiming a better relationship between efficiency and environmental impact. For this, ammonium-modified montmorillonite (AmMt) and phosphonium-modified montmorillonite (PhMt) were prepared according to design of experiments. The samples were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) and contact angle. XRD and TGA analysis showed that the compounds were incorporated in the montmorillonite providing an efficient modification by all the reactional routes employed. The clay interlayer spacing was expanded and AmMt showed the largest d001 while PhMt showed better thermal stability. Statistical analysis indicated that the process parameters had low or no significance in the organo-montmorillonite characteristics. XRD, TGA and FTIR showed that the d001, yield and chemical environment of the O-Mt changed with the amount of organic compound and washing process. The contact angle test showed that the surface tension of montmorillonite was reduced with organophilization. It was concluded that semi-solid method could be a good, efficient and environmentally friendly alternative to prepare O-Mt132-133475484CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ870379/1997-6; 142448/2013-

Processo De Extração E Processo De Purificação Em Série De Substáncias Ativas E Corantes A Partir De Matrizes Sólidas, Utilizando Co2 Supercrìtico: Bixina Proveniente Do Urucum

PROCESSO EQUIPAMENTO DE EXTRAÇÃO E PURIFICAÇÃO EM SÉRIE DE SUBSTÂNCIAS ATIVAS E CORANTES A PARTIR DE MATRIZES SÓLIDAS, UTILIZANDO CO2 SUPERCRITICO: BIXINA PROVENIENTE DO URUCUM. A presente invenção trata de um processo e equipamento para obtenção de fração enriquecida em compostos ativos e/ou corante a partir de matrizes sólidas (folhas, raízes, sementes, etc.) neste caso especial a semente de Urucum (Bixaorellana) reunindo em um único processo: a extração (via tecnologia supercrítica) e a fracionamento/purificação (coluna de adsorção ou eleição) em que o extrator e o fracionador ficam em série. É um processo que não exige etapas posteriores de decantação, filtragem, centrifugação, remoção do solvente ou solução aquosa e secagem. É um processo que pode ocorrer de maneira contínua ou semi-contínua. Além de ser uni processo seletivo, de utilizar um solvente atóxico, inerte, de baixo custo e que não gera resíduo de solvente orgânico; não há contato com a luz durante todo o processo (sendo um diferencial. pois a Bixina é fotodegradável). Outros diferenciais da invenção são que não há contato com O2 (evita degradação de carotenóides) e a extração pode ser feita a temperaturas amenas de processo (por volta de 30 a 70ºC).BRPI0605425 (A)B01D11/02B01D15/40BR2006PI05425B01D11/02B01D15/4

Properties of PLA/PCL particles as vehicles for oral delivery of the androgen hormone 17α-methyltestosterone

The aim of this study was to produce PLA (poly(lactic acid)) and PCL (polycaprolactone) oral carriers through the precipitation of the polymer solutions using supercritical CO2 as an antisolvent for the controlled release of the hydrophobic model drug 17α-methyltestosterone (MT). Such drug is a steroidal hormone used orally to develop and sustain primary and secondary male sex characteristics, e.g. for female Nile tilapia sex reversal in aquaculture. The influence of hormone, PLA and PCL concentrations on particle formation was analyzed, showing that high PCL concentrations produced particles with rougher surfaces and greater mean diameters. The incorporation efficiency of MT ranged from 20 to 51%, and its addition resulted in increases in particle mean diameter from 23 to 54 μm. Aggregation was observed for particles incorporating or not MT and high concentrations of MT led to the formation of more amorphous structures, changing the thermal behavior of the particles. The exposure of the PLA/PCL particles to pH conditions simulating gastrointestinal fish conditions showed that hormone release fraction at acidic pH ranged from 8 to 63% (over 2 h), while in the basic pH the proportion released varied from 23 to 60% (over 10 h), reaching levels adequate for the desired in vivo activity58870881CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ473013/2009-

Properties Of Pla/pcl Particles As Vehicles For Oral Delivery Of The Androgen Hormone 17α-methyltestosterone.

The aim of this study was to produce PLA (poly(lactic acid)) and PCL (polycaprolactone) oral carriers through the precipitation of the polymer solutions using supercritical CO2 as an antisolvent for the controlled release of the hydrophobic model drug 17α-methyltestosterone (MT). Such drug is a steroidal hormone used orally to develop and sustain primary and secondary male sex characteristics, e.g. for female Nile tilapia sex reversal in aquaculture. The influence of hormone, PLA and PCL concentrations on particle formation was analyzed, showing that high PCL concentrations produced particles with rougher surfaces and greater mean diameters. The incorporation efficiency of MT ranged from 20 to 51%, and its addition resulted in increases in particle mean diameter from 23 to 54 μm. Aggregation was observed for particles incorporating or not MT and high concentrations of MT led to the formation of more amorphous structures, changing the thermal behavior of the particles. The exposure of the PLA/PCL particles to pH conditions simulating gastrointestinal fish conditions showed that hormone release fraction at acidic pH ranged from 8 to 63% (over 2h), while in the basic pH the proportion released varied from 23 to 60% (over 10h), reaching levels adequate for the desired in vivo activity.58870-88