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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.
21

Desenvolvimento e otimização de péletes de liberação bifásica mediante delineamento experimental

Martins, Sarah Moherdaui 24 November 2015 (has links)
Made available in DSpace on 2017-05-12T14:36:22Z (GMT). No. of bitstreams: 1 DEFESA_SARAH_M_MARTINS.pdf: 1948811 bytes, checksum: b506b11e5b86370135e564286deabd70 (MD5) Previous issue date: 2015-11-24 / In recent years, the interest of the pharmaceutical industry for new drugs delivery system has been growing, especially aiming the optimization of therapy and reduction of side effects caused by conventional treatments. The multiparticulate systems, besides their techonological and biopharmaceutical advantages when compared to the monolithic systems, allow obtaining different ways of drug delivery, such as the biphasic system, capable of delivering the drug in separate fractions into the bloodstream, and ideal for the treatment of circadian diseases. Thus, this study aimed to obtain a multi particulate system biphasic release, lasting 24 hours, using a combination of polymeric materials hydroxypropyl methylcellulose and ethyl cellulose, as well as a full factorial design 2² to optimize the development stage. Furthermore, it was developed and validated analytical method by UV spectroscopy able to quantify the model drug used, propranolol hydrochloride (PROP) test and the content of dissolution of the dosage form. Using the sugar spheres coating technology, it was possible to obtain the proposed system with a reduced number of experiments. Pellets produced and used in the biphasic formulations showed mechanical characteristics within the expected quality parameters, showing that the technique is robust and can be applied on an industrial scale. The analytical method for the quantification of the proposed drug was linear, precise, accurate, robust against variations in wavelength of mark and sonication solvent in a concentration range of 0.80 - 96 mg L-1 and stable the experimental conditions analyzed, showing a method capable of generating highly reliable results and therefore able to be used in the laboratory routine quality control. / Nos últimos anos, o interesse da indústria farmacêutica por novos sistemas de liberação de fármacos vem crescendo, visando sobretudo a otimização da terapêutica e a diminuição dos efeitos colaterais ocasionados pelos tratamentos convencionais. Os sistemas multiparticulados, além de possuírem vantagens tecnológicas e biofarmacêuticas quando comparadas aos sistemas monolíticos, possibilitam a obtenção de diferentes padrões de liberação de drogas, como por exemplo, o sistema bifásico, capaz de disponibilizar o fármaco em frações distintas para a corrente sanguínea, sendo ideais para o tratamento das doenças circadianas. Desta maneira, o presente trabalho teve como objetivo a obtenção de um sistema multiparticulado de liberação bifásica, com duração de 24 horas, utilizando a combinação dos materiais poliméricos hidroxipropilmetilcelulose e etilcelulose, bem como um planejamento fatorial completo 2² para a otimização da etapa de desenvolvimento. Além disso, foi desenvolvido e validado um método analítico por espectroscopia de UV capaz de quantificar o fármaco modelo utilizado, cloridrato de propranolol (PROP), nos ensaios de teor e dissolução desta forma farmacêutica. Utilizando-se a tecnologia de revestimento de núcleos inertes de sacarose, foi possível a obtenção do sistema proposto com um número reduzido de experimentos. Os péletes produzidos e utilizados nas formulações bifásicas apresentaram características mecânicas dentro dos parâmetros de qualidade esperados, demostrando que a técnica é robusta e pode ser aplicada em escala industrial. O método analítico proposto para a quantificação do fármaco, mostrou-se linear, preciso, exato, robusto em relação a variações no comprimento de onda, marca de solvente e sonicação na faixa de concentração de 0,80 96 μg mL-1 e estável nas condições experimentais analisadas, evidenciando um método capaz de gerar resultados de alta confiabilidade e portanto apto a ser utilizado na rotina laboratorial de controle de qualidade.
22

Synthesis and modification of potential CO2 adsorbents : Amine modified silica and calcium carbonates

Aziz, Baroz January 2012 (has links)
The prospect of rapid changes to the climate due to global warming is subject of public concern. The need to reduce the emissions of atmospheric green house gases and in particular carbon dioxide is greater than ever. Extensive research is performed to find new solutions and new materials, which tackles this problem in economically benign way. This thesis dealt with two potential adsorbents for post combustion  carbon capture, namely, amine modified silica and calcium carbonates. We modified porous silica with large surface area by propyl-amine groups to enhance the carbon dioxide adsorption capacity and selectivity. Experimental parameters, such as reaction time, temperature, water content, acid and heat treatment of silica substrate were optimized using a fractional factorial design. Adsorption properties and the nature of formed species upon reaction of CO2 and amine-modified silica were studied by sorption and infrared spectroscopy. Physisorbed and chemisorbed amount of adsorbed CO2 were, for the first time, estimated directly in an accurate way. The effects of temperature and moisture on the CO2 adsorption properties were also studied. Crystallization of calcium carbonate as a precursor to calcium oxide, which can be used as carbon dioxide absorbent, was studied in the second part of this thesis. Structure of different amorphous phases of calcium carbonate was studied in detail. Crystallization of calcium carbonate with and without additives was studied. Parameters like stirring rate, temperature, pH and polymer concentration showed to be important in selection of phase and morphology. An aggregation mediated crystallization was postulated to explain the observed morphologies. / At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Accepted.
23

Contributions to variable selection for mean modeling and variance modeling in computer experiments

Adiga, Nagesh 17 January 2012 (has links)
This thesis consists of two parts. The first part reviews a Variable Search, a variable selection procedure for mean modeling. The second part deals with variance modeling for robust parameter design in computer experiments. In the first chapter of my thesis, Variable Search (VS) technique developed by Shainin (1988) is reviewed. VS has received quite a bit of attention from experimenters in industry. It uses the experimenters' knowledge about the process, in terms of good and bad settings and their importance. In this technique, a few experiments are conducted first at the best and worst settings of the variables to ascertain that they are indeed different from each other. Experiments are then conducted sequentially in two stages, namely swapping and capping, to determine the significance of variables, one at a time. Finally after all the significant variables have been identified, the model is fit and the best settings are determined. The VS technique has not been analyzed thoroughly. In this report, we analyze each stage of the method mathematically. Each stage is formulated as a hypothesis test, and its performance expressed in terms of the model parameters. The performance of the VS technique is expressed as a function of the performances in each stage. Based on this, it is possible to compare its performance with the traditional techniques. The second and third chapters of my thesis deal with variance modeling for robust parameter design in computer experiments. Computer experiments based on engineering models might be used to explore process behavior if physical experiments (e.g. fabrication of nanoparticles) are costly or time consuming. Robust parameter design (RPD) is a key technique to improve process repeatability. Absence of replicates in computer experiments (e.g. Space Filling Design (SFD)) is a challenge in locating RPD solution. Recently, there have been studies (e.g. Bates et al. (2005), Chen et al. (2006), Dellino et al. (2010 and 2011), Giovagnoli and Romano (2008)) of RPD issues on computer experiments. Transmitted variance model (TVM) proposed by Shoemaker and Tsui. (1993) for physical experiments can be applied in computer simulations. The approaches stated above rely heavily on the estimated mean model because they obtain expressions for variance directly from mean models or by using them for generating replicates. Variance modeling based on some kind of replicates relies on the estimated mean model to a lesser extent. To the best of our knowledge, there is no rigorous research on variance modeling needed for RPD in computer experiments. We develop procedures for identifying variance models. First, we explore procedures to decide groups of pseudo replicates for variance modeling. A formal variance change-point procedure is developed to rigorously determine the replicate groups. Next, variance model is identified and estimated through a three-step variable selection procedure. Properties of the proposed method are investigated under various conditions through analytical and empirical studies. In particular, impact of correlated response on the performance is discussed.
24

Investigation of the Impact on Yeast Fermentation Performance in Production of Pale Lager Beer through Management Control / Utredning av påverkan på jästfermentering genom hanteringsstyrning vid produktion av ljus lageröl

Skogsberg, Zara January 2013 (has links)
Through a full factorial design experiment, the effects of time between worts, wort aeration and yeast dosage in production of a pale lager beer were examined in the beer process at Spendrups Bryggeri AB. The aim was to learn how different parameters may affect the yeast fermentation performance during beer production. Response variables used were the concentrations of ethyl acetate and isoamyl acetate, free amino nitrogen (FAN) degradation and change in extract. A statistical analysis showed that the concentration of ethyl acetate is dependent on yeast dosage and the interaction between time between worts and aeration while the isoamyl acetate concentration is dependent on yeast dosage and time between worts. No parameters are statistically significant for FAN degradation while the change in extract is dependent on the yeast dosage. Due to botched runs, mostly because of aeration problems, it was not possible to verify theoretical parameter values and responses. Since the aeration was not properly performed, the management of the aeration control should be further investigated. Ester analysis and analysis of FAN were performed as worts entered and exited horizontal fermentation tanks. An additional analysis of ester content was also performed as the early stage beer was transferred into lagering tanks. Cell viability as well as extract, pH and tank temperature was measured daily to verify the state of fermentation. Statistical calculations showed that when using NucleoCounter YC-100, there is no significant difference between analysis made of samples homogenized by a magnetic stirrer and samples shaken by hand.
25

Assessment and Optimization of Ex-Situ Bioremediation of Petroleum Contaminated Soil under Cold Temperature Conditions

Gomez, Francisco 04 February 2014 (has links)
Current prices and demand for petroleum hydrocabons have generated an increase of oil spills around the country and the world. Health and environmental impacts associated to these organic pollutants represent a huge concern for the general public, leading the public and private sector to develop new technologies and methods to minimize or eliminate those risks. Ex-Situ bioremediation through biopiles, as a main remediation technique to treat a wide range of hydrocarbons, has been a topic of considerable research interest over the last years. It provides an economical and environmental solution to restore the environment to background levels. Nevertheless, successful bioremediation under cold climate conditions is of considerable concern in countries like Canada, as low temperatures can delay the rate of bioremediation of oil hydrocarbons, thus limiting the operation of soil treatment facilities to certain times of the year. Recent research has found out that bioremediation could be conducted even at low or cold temperatures with larger periods of times. And even more, the addition of petroleum degrading microorganisms (bioaugmentation) and nutrients or biosurfactants (biostimulation) could enhance the process in some cases. In the present study, a comprehensive assessment of bioaugmentation and biostimulation strategies for ex-situ bioremediation of petroleum contaminated soil under cold climate conditions is proposed. Field scale biopiles were constructed and subjected to different concentrations of commercial microbial consortia and mature compost, as bioaugmentation and biostimulation strategies, in a soil treatment facility at Moose Creek, Ontario over a period of 94 days (November 2012 to February 2013). Assessment and comparison of the biodegradation rates of total petroleum hydrocarbons (TPH) and their fractions were investigated. Furthermore, a response surface methodology (RSM) based on a factorial design to investigate and optimize the effects of the microbial consortia application rate and amount of compost on the TPH removal was also assessed. Results showed that biopiles inoculated with microbial consortia and amended with 10:1 soil to compost ratio under aerobic conditions performed the best, degrading 82% of total petroleum hydrocarbons (TPHs) with a first-order kinetic degradation rate of 0.016 d_1, under cold temperature conditions. The average removal efficiencies for TPHs after 94 days for control biopiles, with no amendments or with microbial consortia or compost only treatments were 48%, 55%, and 52%, respectively. Statistical analyses indicated a significant difference (p < 0.05) within and between the final measurements for TPHs and a significant difference between the treatment with combined effect, and the control biopiles. On the other hand, the modeling and optimization statistical analysis of the results showed that the microbial consortia application rate, compost amendment and their interactions have a significant effect on TPHs removal with a coefficient of determination (R2) of 0.88, indicating a high correlation between the observed and the predicted values for the model obtained. The optimum concentrations predicted via RSM were 4.1 ml m-3 for microbial consortia application rate, and 7% for compost amendment to obtain a maximum TPH removal of 90.7%. This research contributes to provide valuable knowledge to practitioners about cost-effective and existing strategies for ex-situ bioremediation under cold weather conditions.
26

Influência de adjuvantes sobre as características farmacêuticas de cápsulas de gelatina dura contendo hidroclorotiazida

Guterres, Silvia Stanisçuaski January 1990 (has links)
A biodisponibilidade é uma característica decisiva para a eficácia dos medicamentos, podendo sua intensidade ser estimada através da cedência "in vitro". Vários fatores são capazes de influenciá-la, entre eles a composição quali e quantitativa dos adjuvantes, assim como as características da substância ativa e da forma farmacêutica. A hidroclorotiazida é um diurético de amplo emprego, que apresenta problemas de biodisponibilidade e bioequivalência devido a sua baixa hidrossolubilidade. Através de planejamento fatorial 2 3 foram preparadas formulações de cápsulas de gelatina dura contendo 50 mg de hidroclorotiazida. Foi analisada a influência dos fatores material de enchimento (lactose e celulose microcristalina), reguladores de fluxo (dióxido de silício altamente disperso e estearato de magnésio) e hidrofilizante (polissorbato 80) sobre as características de qualidade dos complexos farmacêuticos e das cápsulas. O regulador de fluxo ou a interação entre este e o material de enchimento foram os fatores determinantes nas características de fluxo dos complexos farmacêuticos, analisadas através do ângulo de repouso e do índice de compressibilidade. A cedência "in vitro" das cápsulas, determinada com auxílio de aparelho de célula de fluxo e parametrizada pela eficiência de dissolução, foi influenciada preponderantemente pelo regulador de fluxo. Foram comparados os perfis de cedência "in vitro" entre as cápsulas e comprimido do mercado. O comportamento intermediário demonstrado pelo comprimido indica a necessidade de avaliação comparativa entre medicamentos contendo hidroclorotiazida a fim de assegurar sua bioequivalência. / The bioavailability is a decisive characteristic to drugs efficacy that can be predict by different "in vitro" dissolution methods. The bioavailability has been shown to be dependent on factors such as the drug, the dosage forms, type and quality of adjuvants. Hydrochlorothiazide is a widely used diuretic. Due to its limited aqueous solubility, this drug has potencial bioavailability problems. Eight differents hydrochlorothiazide hard gelatin capsules, containing 50 mg of the drug, were prepared according to a 2 3 factorial design. The influence of fillers (lactose or microcrystaline cellulose), glidants (magnesium stearate or coloidal silicon dioxide) and surfactant (polysorbate 80) on the pharmaceutical characteristics of powder mixtures and capsules were evaluated. The powder mixtures flow characteristics were evaluated through repose angle and compressibility index. It was determined that the glidant and its interaction with filler influenced this characteristic. The "in vitro" release of hydrochlorothiazide from capsules was carried out by a open flow-though dissolution method. The dissolution efficiency was the selected parameter to express the drug release. The glidant was the determinant factor. The dissolution profile of these capsules and marketed tablets was compared. The results evidenced the importance of comparative evaluation of hydrochlorothiazide dosage forms to assure their bioequivalence.
27

Produção biotecnológica de hidrogênio, 1,3-Propanodiol e etanol utilizando glicerol residual proveniente da síntese de biodiesel

Rossi, Daniele Misturini January 2012 (has links)
O glicerol é gerado em grandes quantidades durante a produção de biodiesel e tem se tornado um substrato potencialmente atrativo para a produção bacteriana de produtos de valor agregado, tais como 1,3-Propanodiol (1,3-PD), etanol, hidrogênio e outros. O presente trabalho teve como objetivo a produção de hidrogênio, 1,3-PD e etanol utilizando glicerol residual obtido da síntese do biodiesel. A primeira parte do trabalho visou à produção de hidrogênio utilizando glicerol residual. Nesta etapa, o consórcio microbiano ambiental foi submetido a diferentes tratamentos (ácido, básico, choque térmico, congelamento e descongelamento e dessecação). Os resultados mostraram que a maior produção de hidrogênio ocorreu com o consórcio tratado com dessecação e choque térmico, com produções de 34,2 % mol e 27,3 % mol, respectivamente. A otimização da produção de hidrogênio foi realizada utilizando planejamento experimental e alcançou uma produção máxima de 45 % mol. A próxima etapa do projeto foi isolar as bactérias presentes no consórcio microbiano ambiental. Experimentos em biorreatores foram realizados utilizando glicerol puro e glicerol residual e os resultados mostraram que houve a completa degradação do glicerol pelas bactérias do consórcio e também a produção de 1,3-PD, hidrogênio e ácidos. Nesta etapa, 32 bactérias foram isoladas e testadas para a produção de bioprodutos em experimentos em aerobiose e anaerobiose. Quatro bactérias foram selecionadas e o seqüenciamento do gene foi identificado por 16S rRNA identificou três dos isolados como Klebsiella pneumoniae e um isolado como Pantoea agglomerans. Dentre as quatro bactérias, uma cepa, nomeada como K. pneumoniae BLh-1, foi selecionada para os trabalhos posteriores. Para otimização das condições de cultivo, utilizou-se a seleção de variáveis através do delineamento experimental Plackett Burman (P-B) avaliando a produção de 1,3-PD. Sete variáveis foram estatisticamente significativas e um novo planejamento fracionário 27-3 foi realizado com a finalidade de otimizar o meio de produção. Experimentos em biorreatores mostraram que a produção em bioreator com pH controlado com o meio otimizado no planejamento alcançou uma produção máxima de 23,80 g/L de 1,3-PD com produção de 12,30 g/L de etanol. Os ensaios com alimentação de glicerol residual mostraram que altas taxas de alimentação causam acúmulo de glicerol e diminuem a produtividade de 1,3-PD e etanol. Os estudos utilizando fluorescência 2D e modelo quimiométrico foram aplicados para avaliar as mudanças metabólicas nos cultivos aeróbios e anaeróbios. Os resultados mostraram que houve diferença nas regiões de NADH e riboflavinas ambas associadas ao metabolismo do microorganismo. / Glycerol is generated in large amounts during biodiesel production and it is becoming a potentially attractive substrate for bacterial production for value-added products such as 1,3-propanediol (1,3-PD), ethanol, hydrogen, among others. This work aimed at studying the production of hydrogen, 1,3-PD and ethanol using the raw glycerol obtained by biodiesel synthesis. The first steps were to produce hydrogen using raw glycerol. At this step, the environmental microbial consortium was submitted to different pretreatments (acid, base, heat shock, dry heat and desiccation, freezing and thawing). The results showed that dry heat and desiccation had the higher hydrogen production followed by heat shock with production of 34.2 % mol and 27.3 % mol, respectively.The optimization of hydrogen production was performed using experimental design and had a maximum hydrogen production of 45 % mol. The next spet of this project was to isolate the bacteria present in an environmental microbial consortium. Experiments in bioreactors with the microbial consortium using raw and pure glycerol were carried out and the results showed that there was a complete glycerol degradation by microbial bacteria with productions of 1,3-PD, hydrogen and acids. In this step, 32 bacteria were isolated and tested separately for by-products production under aerobic and anaerobic conditions. Four bacteria were selected and sequence gene realized by 16 S rRNA, three of them were identified as Klebsiella pneumoniae and one isolate identified as Pantoea agglomerans. Among the four bacteria, the strain K. pneumoniae BLh-1 were selected for further experiments. Plackett Burman (P-B) experimental procedure was used for assessing the production of 1,3-PD. Seven variables were statistically significant and a new 27-3 fractional design was conducted with the aim of optimizing culture conditions. Bioreactors experiments using the optimized culture conditions showed that production in bioreactor with controlled pH reached a maximal 1,3-PD production of 23.80 g/L with 12.30 g/L of ethanol. The fed-batch experiments showed that high feeding rates caused glycerol to accumulated in the medium and the1,3-PD and ethanol productivity decreased. The 2D fluorescence metodology was applied in order to study the anaerobic-aerobic changes on K. pneumoniae metabolism. The results showed a significant difference on NADH and riboflavin fluorescence that are fluorescence regions associated to metabolism.
28

Influência de adjuvantes sobre as características farmacêuticas de cápsulas de gelatina dura contendo hidroclorotiazida

Guterres, Silvia Stanisçuaski January 1990 (has links)
A biodisponibilidade é uma característica decisiva para a eficácia dos medicamentos, podendo sua intensidade ser estimada através da cedência "in vitro". Vários fatores são capazes de influenciá-la, entre eles a composição quali e quantitativa dos adjuvantes, assim como as características da substância ativa e da forma farmacêutica. A hidroclorotiazida é um diurético de amplo emprego, que apresenta problemas de biodisponibilidade e bioequivalência devido a sua baixa hidrossolubilidade. Através de planejamento fatorial 2 3 foram preparadas formulações de cápsulas de gelatina dura contendo 50 mg de hidroclorotiazida. Foi analisada a influência dos fatores material de enchimento (lactose e celulose microcristalina), reguladores de fluxo (dióxido de silício altamente disperso e estearato de magnésio) e hidrofilizante (polissorbato 80) sobre as características de qualidade dos complexos farmacêuticos e das cápsulas. O regulador de fluxo ou a interação entre este e o material de enchimento foram os fatores determinantes nas características de fluxo dos complexos farmacêuticos, analisadas através do ângulo de repouso e do índice de compressibilidade. A cedência "in vitro" das cápsulas, determinada com auxílio de aparelho de célula de fluxo e parametrizada pela eficiência de dissolução, foi influenciada preponderantemente pelo regulador de fluxo. Foram comparados os perfis de cedência "in vitro" entre as cápsulas e comprimido do mercado. O comportamento intermediário demonstrado pelo comprimido indica a necessidade de avaliação comparativa entre medicamentos contendo hidroclorotiazida a fim de assegurar sua bioequivalência. / The bioavailability is a decisive characteristic to drugs efficacy that can be predict by different "in vitro" dissolution methods. The bioavailability has been shown to be dependent on factors such as the drug, the dosage forms, type and quality of adjuvants. Hydrochlorothiazide is a widely used diuretic. Due to its limited aqueous solubility, this drug has potencial bioavailability problems. Eight differents hydrochlorothiazide hard gelatin capsules, containing 50 mg of the drug, were prepared according to a 2 3 factorial design. The influence of fillers (lactose or microcrystaline cellulose), glidants (magnesium stearate or coloidal silicon dioxide) and surfactant (polysorbate 80) on the pharmaceutical characteristics of powder mixtures and capsules were evaluated. The powder mixtures flow characteristics were evaluated through repose angle and compressibility index. It was determined that the glidant and its interaction with filler influenced this characteristic. The "in vitro" release of hydrochlorothiazide from capsules was carried out by a open flow-though dissolution method. The dissolution efficiency was the selected parameter to express the drug release. The glidant was the determinant factor. The dissolution profile of these capsules and marketed tablets was compared. The results evidenced the importance of comparative evaluation of hydrochlorothiazide dosage forms to assure their bioequivalence.
29

Aplicação de processos oxidativos avançados na degradação de propranolol e avaliação de sua toxicidade

Fernandes, Abraão Augusto 28 August 2015 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-05-05T14:14:50Z No. of bitstreams: 1 arquivo total.pdf: 4535008 bytes, checksum: 35f2a65a445c1e8219acb5615d951d72 (MD5) / Made available in DSpace on 2016-05-05T14:14:50Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 4535008 bytes, checksum: 35f2a65a445c1e8219acb5615d951d72 (MD5) Previous issue date: 2015-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The presence of drug residues has been found in aquatic environments, such as; lakes and rivers and in most cases this type contaminant is found in sewers. This type of pharmaceutical waste may contain an antihypertensive drug class, and one of its main representatives is propranolol (PRO). As a result, this study aimed to apply the advanced oxidation processes (AOPs) as an alternative to removal of this drug in synthetic effluent (SE) and real (RE). This study employed in a photochemical reactor, homogeneous systems of type photolysis, UV/H2O2, Fenton, photo-Fenton, like that TiO2 and ZnO as methods based on heterogeneous catalysis. The parameters for optimization of these methods were evaluated with the assistance of full factorial design. The evaluation of the optimal methods was performed based on the values of the rate of degradation, chemical oxygen demand (COD) and the germination index (GI). The results of better rate degradation (98,3 and 88.6%), reduction of COD (47 and 29.4%) and germination rate (62,2 and 47.2%), were achieved employing a UVC lamp 60W in the method photo-Fenton with a H2O2 concentration of 6 mmol L-1 and a Fe2+ concentration of 0.2 mmol L-1 for the synthetic and real effluent. / ambientes aquáticos, tais como; lagos e rios, e na maioria dos casos esse tipo de contaminante é encontrado em esgotos. Este tipo de efluentes das indústrias farmacêuticas pode conter uma classe de fármaco antihipertensivos, e um de seus principais representantes é o propranolol (PRO). Em vista disso, o presente trabalho visou aplicar processos oxidativos avançados (POAs) como alternativa na remoção desse fármaco em efluente sintético (ES) e real (ER). Nesse estudo foram empregados, em um reator fotoquímico, sistemas homogêneos do tipo fotólise, UV/H2O2, Fenton, foto-Fenton, bem como TiO2 e ZnO, como semicondutores para a catálise heterogênea. Os parâmetros para otimização desses métodos foram avaliados com o auxílio de planejamentos fatoriais completos. A avaliação dos métodos otimizados foi realizada com base nos valores da taxa de degradação, DQO e índice de germinação. Os melhores resultados de taxa de degradação (98,3 e 88,6%), redução de DQO (47 e 29,4%) e índice de germinação (62,2 e 47,0%) foram alcançados com o método foto-Fenton empregando lâmpada UVC com 60W de potência, concentração de H2O2 4 mmolL-1 e concentração de Fe2+ 0,12 mmolL-1, para o efluente sintético e real.
30

Produção biotecnológica de hidrogênio, 1,3-Propanodiol e etanol utilizando glicerol residual proveniente da síntese de biodiesel

Rossi, Daniele Misturini January 2012 (has links)
O glicerol é gerado em grandes quantidades durante a produção de biodiesel e tem se tornado um substrato potencialmente atrativo para a produção bacteriana de produtos de valor agregado, tais como 1,3-Propanodiol (1,3-PD), etanol, hidrogênio e outros. O presente trabalho teve como objetivo a produção de hidrogênio, 1,3-PD e etanol utilizando glicerol residual obtido da síntese do biodiesel. A primeira parte do trabalho visou à produção de hidrogênio utilizando glicerol residual. Nesta etapa, o consórcio microbiano ambiental foi submetido a diferentes tratamentos (ácido, básico, choque térmico, congelamento e descongelamento e dessecação). Os resultados mostraram que a maior produção de hidrogênio ocorreu com o consórcio tratado com dessecação e choque térmico, com produções de 34,2 % mol e 27,3 % mol, respectivamente. A otimização da produção de hidrogênio foi realizada utilizando planejamento experimental e alcançou uma produção máxima de 45 % mol. A próxima etapa do projeto foi isolar as bactérias presentes no consórcio microbiano ambiental. Experimentos em biorreatores foram realizados utilizando glicerol puro e glicerol residual e os resultados mostraram que houve a completa degradação do glicerol pelas bactérias do consórcio e também a produção de 1,3-PD, hidrogênio e ácidos. Nesta etapa, 32 bactérias foram isoladas e testadas para a produção de bioprodutos em experimentos em aerobiose e anaerobiose. Quatro bactérias foram selecionadas e o seqüenciamento do gene foi identificado por 16S rRNA identificou três dos isolados como Klebsiella pneumoniae e um isolado como Pantoea agglomerans. Dentre as quatro bactérias, uma cepa, nomeada como K. pneumoniae BLh-1, foi selecionada para os trabalhos posteriores. Para otimização das condições de cultivo, utilizou-se a seleção de variáveis através do delineamento experimental Plackett Burman (P-B) avaliando a produção de 1,3-PD. Sete variáveis foram estatisticamente significativas e um novo planejamento fracionário 27-3 foi realizado com a finalidade de otimizar o meio de produção. Experimentos em biorreatores mostraram que a produção em bioreator com pH controlado com o meio otimizado no planejamento alcançou uma produção máxima de 23,80 g/L de 1,3-PD com produção de 12,30 g/L de etanol. Os ensaios com alimentação de glicerol residual mostraram que altas taxas de alimentação causam acúmulo de glicerol e diminuem a produtividade de 1,3-PD e etanol. Os estudos utilizando fluorescência 2D e modelo quimiométrico foram aplicados para avaliar as mudanças metabólicas nos cultivos aeróbios e anaeróbios. Os resultados mostraram que houve diferença nas regiões de NADH e riboflavinas ambas associadas ao metabolismo do microorganismo. / Glycerol is generated in large amounts during biodiesel production and it is becoming a potentially attractive substrate for bacterial production for value-added products such as 1,3-propanediol (1,3-PD), ethanol, hydrogen, among others. This work aimed at studying the production of hydrogen, 1,3-PD and ethanol using the raw glycerol obtained by biodiesel synthesis. The first steps were to produce hydrogen using raw glycerol. At this step, the environmental microbial consortium was submitted to different pretreatments (acid, base, heat shock, dry heat and desiccation, freezing and thawing). The results showed that dry heat and desiccation had the higher hydrogen production followed by heat shock with production of 34.2 % mol and 27.3 % mol, respectively.The optimization of hydrogen production was performed using experimental design and had a maximum hydrogen production of 45 % mol. The next spet of this project was to isolate the bacteria present in an environmental microbial consortium. Experiments in bioreactors with the microbial consortium using raw and pure glycerol were carried out and the results showed that there was a complete glycerol degradation by microbial bacteria with productions of 1,3-PD, hydrogen and acids. In this step, 32 bacteria were isolated and tested separately for by-products production under aerobic and anaerobic conditions. Four bacteria were selected and sequence gene realized by 16 S rRNA, three of them were identified as Klebsiella pneumoniae and one isolate identified as Pantoea agglomerans. Among the four bacteria, the strain K. pneumoniae BLh-1 were selected for further experiments. Plackett Burman (P-B) experimental procedure was used for assessing the production of 1,3-PD. Seven variables were statistically significant and a new 27-3 fractional design was conducted with the aim of optimizing culture conditions. Bioreactors experiments using the optimized culture conditions showed that production in bioreactor with controlled pH reached a maximal 1,3-PD production of 23.80 g/L with 12.30 g/L of ethanol. The fed-batch experiments showed that high feeding rates caused glycerol to accumulated in the medium and the1,3-PD and ethanol productivity decreased. The 2D fluorescence metodology was applied in order to study the anaerobic-aerobic changes on K. pneumoniae metabolism. The results showed a significant difference on NADH and riboflavin fluorescence that are fluorescence regions associated to metabolism.

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