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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.
261

A study of electrospun nanofibers and diatomaceous earth materials for the extraction of alkaloids, flavonoids and aromatic amines in various matrices / Study of electrospun nanofibres and diatomaceous earth materials for the extraction of alkaloids, flavonoids and aromatic amines in various matrices

Mothibedi, Kediemetse (Kedimetse) 07 April 2013 (has links)
The thesis explored the use of different sorbent materials in solid phase extraction method development. The methods included the use of the polymeric Agilent Bond Elut Plexa solid phase extraction and electrospun polymer-silica composite sorbents for clean-up and preconcentration. Sample clean-up for alkaloids (hydrastine and berberine) in goldenseal, Hydrastis canadensis and flavonoids (quercetin, kaempferol and isorhamnetin) in Ginkgo biloba was achieved using Bond Elut Plexa SPE sorbent. Clean-up of flavonoids in Ginkgo biloba was also achieved using electrospun polymer-silica composite (polystyrene-silica, polyacrylonitrile-silica and nylon 6-silica) sorbents. All analysis of flavonoids and alkaloids was carried out using an Agilent 1200 Series HPLC coupled with a diode array detector. Good peak separation was achieved in less than 6 min employing an Agilent ZORBAX Eclipse Plus C18 column (4.6 x 75 mm, 3.5 μm) at 35⁰C. The mobile phases employed were 0.1% phosphoric acid/methanol gradient and 0.5% phosphoric acid/methanol (40:60) for alkaloids and flavonoids respectively. The calibration curves exhibited linearity up to 120 μg mL⁻¹ with correlation coefficients of more than 0.9980. The recoveries ranged from 73-109% with relative standard deviation of less than 5% for all analytes. Agilent Chem Elut supported liquid extraction was employed for the development of a sample preparation method for the determination of 24 banned aromatic amines from azo dyes in textile following the EU standard method EN 14362-1:2003 (E) and the Chinese standard method GB/T 17592-2006. The supported liquid extraction was effective in the extraction of the aromatic amines from textile (cotton, wool and polyester/cotton [80%:20%]). Most of the recoveries obtained were conforming to the minimum requirements set in the EN 14362-1:2003 (E) standard method and the relative standard deviations were less than 15%. Good peak separation was obtained within 70 min run time using the Agilent Zorbax SB-Phenyl column (4.6 mm x 250 mm, 5-micron) or the Agilent DB-35 MS (J & W) (30 m x 0.25 mm, 0.25 μm film thickness. It was demonstrated that the polymeric Agilent Bond Elut Plexa, electrospun nanofibers and diatomaceous earth were effective in extraction of alkaloids, flavonoids and aromatic amines in different matrices. The developed methods were simple, rapid and reproducible.
262

Tratamento eletroquímico e físico-químico para efluente de lavanderia industrial têxtil

Gonçalves, Leandro Vicente 26 March 2015 (has links)
CAPES / A lavanderia industrial têxtil é caracterizada pela variedade dos processos aplicados, pelo alto volume de efluentes gerados e pela carga poluidora. A caracterização física e química destes efluentes é de suma importância para determinação do tratamento apropriado, bem como para avaliação dos agentes poluentes e seus impactos potenciais. Desta forma, o desenvolvimento do presente estudo permite o aperfeiçoamento do conhecimento acerca dos processos eletroquímicos e físico-químico para a remoção de cor e carga orgânica em efluentes de lavanderia industrial têxtil. Os experimentos foram realizados em quatro processos: - 1: ensaios de eletrocoagulação / eletrofloculação / eletroflotação utilizando reator em escala de laboratório tipo tanque agitado, com o emprego de eletrodos de alumínio e carbono. - 2: ensaios físico-químicos utilizando o processo de flotação por ar dissolvido (FAD) em unidade de escala de bancada (flotateste) com o uso de tanino “Tanfloc SG”. - 3: ensaios FAD com o uso de policloreto de alumínio (PAC) e polímero aniônico. - 4: ensaios FAD com o uso de sementes de Moringa Oleífera. A metodologia utilizada para os ensaios de todos os processos foram o planejamento experimental do delineamento composto central rotacional DCCR com dois parâmetros avaliados para cada processo: - 1: corrente elétrica, e tempo de eletrocoagulação; - 2: dosagem de coagulante tanino e pH da solução; - 3: dosagem de coagulantes PAC e polímero aniônico; - 4: dosagem de coagulante moringa e pH da solução. Após o término dos ensaios, amostras do efluente tratado foram analisadas para determinação da eficiência de remoção das variáveis cor aparente, turbidez, demanda química de oxigênio (DQO) e sólidos suspensos totais (SST). No processo 1, o eletroquímico foi obtido uma eficiência ótima para a remoção de cor aparente, turbidez, DQO e SST de 86%; 58,93%; 75,2% e 66,3%, respectivamente. Para os ensaios FAD, a eficiência máxima para a remoção de cor aparente, turbidez, DQO e SST foi de 90%; 96,90%; 61,4% e 94,1%, respectivamente, para o processo 2, de 93%; 93,65%; 71,8% e 88,8%, respectivamente, para o processo 3, e de 65%; 80,00%; 40,2% e 62,3%, respectivamente, para o processo 4. Os resultados obtidos indicaram que apenas o experimento utilizando o processo FAD com o coagulante moringa oleífera não foi uma opção viável por ultrapassar o padrão de qualidade da variável cor aparente exigido pela a resolução CONAMA 357. Os demais processos e coagulantes estudados neste trabalho podem ser utilizados como alternativas tecnicamente viáveis para a remoção de cor aparente, turbidez, DQO e SST de efluentes de lavanderia têxtil. / The textile industrial laundry is characterized by the variety of existing processes, the large volume of wastewater and high polluting load. Physical and chemical characterization of these effluents is important to determine the appropriate treatment and to assess pollutants and their potential impacts. Thus, the development of this study allows contribute to the knowledge of the electrochemical processes and physical chemistry in order to remove the color and organic load in textile industrial laundry wastewater. The experiments were performed in four processes: - 1: electrocoagulation / electroflocculation / electrocoagulation tests using reactor at laboratory scale stirred tank with the use of aluminum and carbon electrodes. - 2: physico-chemical tests using process by dissolved air flotation (DAF) with a bench scale unit (flotatest) using tannin "Tanfloc SG". - 3: tests DAF using polyaluminum chloride (PAC) and anionic polymer. - 4: tests DAF using seeds of Moringa oleífera. The methodology used for the testing of all processes was the experimental design central composite rotational design (RCCD) with two parameters assessed for each process: - 1: electric current and electrocoagulation time; - 2: tannin dosage as coagulant and pH solution; - 3: PAC dosage as coagulant and anionic polymer; - 4: moringa dosage as coagulant and pH solution. At the end of the tests, samples of treated wastewater were analyzed to determine the removal efficiency of apparent color, turbidity, chemical oxygen demand (COD) and total suspended solids (TSS). In the process 1, optimal efficiency the electrochemical of process for the removal of apparent color, turbidity, COD and TSS 86%; 58.93%; 75.2% and 66.3%, respectively. For the DAF tests, the maximum efficiency for the removal of apparent color, turbidity, COD and TSS for process 2 was 90%; 96.90%; 61.4% and 94.1%, respectively, for process 3 was 93%; 93.65%; 71.8% and 88.8%, respectively; and for process 4 was 65%; 80.00%; 40.2% and 62.3%, respectively. The results indicated that only the experiment using the DAF process with the moringa oleífera coagulant was not a viable option, because it exceeds the quality standard of the apparent color required by the resolution CONAMA 357. The processes and coagulants studied in this work can be used as technically feasible alternatives to removal apparent color, turbidity, COD and TSS of textile industrial laundry wastewater.
263

Remoção dos corantes têxteis C.I. Reactive Blue 203 e C.I. Reactive Red 195 mediante o uso de bagaço de maçã como adsorvente

Marin, Sandra Liliana Albornoz 07 August 2015 (has links)
CNPq / A indústria têxtil tem grande impacto ambiental devido ao seu amplo consumo de água e da utilização de diferentes produtos químicos orgânicos como os corantes. Existem diferentes métodos utilizados no tratamento de efluentes têxteis, sendo um deles, a adsorção. A utilização de resíduos agroindustriais como adsorventes é uma alternativa para a descontaminação de efluentes com corantes. Desta forma, este trabalho teve por objetivo avaliar o resíduo agroindustrial de Bagaço de Maçã da variedade Fuji, proveniente da produção de sucos, como adsorvente alternativo na remoção de corantes têxteis C.I. Reactive Blue 203 e C.I. Reactive Red 195 em meio aquoso sintético. As características do adsorvente mostraram que o bagaço de maçã apresenta 89,36% de umidade, 35,64% de fibra bruta e a 52,72% de carbono. O pH(pcz) é de 3,5 e em sua superfície predomina sítios ácidos. Na espectroscopia do infravermelho observou-se a presença dos principais grupos funcionais (–OH), (–NH), (CH2), (–CO), (–C–O–), na microscopia eletrônica de varredura a morfologia da superfície do bagaço de maçã mostrou-se porosa e a determinação das características texturais indicaram uma área superficial de 2,088 (m2.g-1) para o tamanho de partícula de 0,125 mm. A partir dos resultados do planejamento experimental - 23, pode-se otimizar o processo de adsorção para os dois corantes pelo bagaço de maçã fixando as variáveis independentes com influência significativa (pH de 2,0 e granulometria do adsorvente em 0,125 mm). No estudo cinético o tempo de equilíbrio para o Reactive Blue 203 foi de 420 minutos e para Reactive Red 195 de 180 minutos e o ajuste matemático para ambos corantes foi para o modelo de pseudo-segunda ordem. As isotermas de equilíbrio foram testadas pelos modelos das isotermas de adsorção de Langmuir, Freundlich, Dubinin-Raduskevich e BET, sendo este último mais adequado para a descrição do processo. Os parâmetros termodinâmicos foram determinados em diferentes faixas de temperatura, em que valores negativos de ΔG° indicam a espontaneidade do processo de adsorção para os dois corantes e valores negativos para ΔH° no processo de adsorção do corante Reactive Blue 203 indicam natureza exotérmica no entanto para adsorção do corante Reactive Red 195 valores positivos de ΔH° sugerem a sua natureza endotérmica. Os valores de ΔH e Ea para a adsorção dos dois corantes em bagaço de maçã mostram que são da mesma ordem de grandeza que o calor e a energia de ativação da quimissorção. O bagaço de maçã mostrou-se altamente favorável para o processo de adsorção dos corantes Reactive Blue 203 e Reactive Red 195. / The textile industry has a big environmental impact because consume a lot of water, and use different chemical organic products like dyes. There are different methods for treatment of textile effluents one of those is adsorption. Using agroindustrial residues like adsorbents is an alternative for decontamination effluents by dyes. Therefore, this present work aimed to evaluate agroindustrial residue apple pomace of Fuji variety, that proceed of production of juices, like alternative adsorbent for the removal textile dyes C.I. Reactive Blue 203 and C.I. Reactive Red 195 in aqueous synthetic medium. The adsorbent characteristics showed that apple pomace present 89.36% of humidity and 35,64% of crude fiber. and 52,72% of C. The pH (pzc) is 3,5, and its surface prevails sites acids. In infrared spectroscopy it was observed the presence of the major functional groups (–OH), (–NH), (CH2), (–CO), (–C–O–). In scanning electron microscopy of the surface morphology of the apple pomace was found to be porous and determining the textural features indicated a surface area of 2,088 (m2.g-1) to 0,125 mm particle size. From the results of the experimental design 23 can optimize the process of adsorption of for both dyes by apple pomace, setting the independent variables with significant influence (pH of 2.0 and particle size of the adsorbent 0.125 mm). In the kinetic study the equilibrium time for Reactive Blue 203 was 420 minutes and for Reactive Red 195 was 180 minutes and for both dyes mathematical adjustment was to model the pseudo-second order. The equilibrium isotherms were tested by the models adsorption isotherms of Langmuir, Freundlich, Dubinin-Raduskevich and BET, the last being more suitable for the description of the process. The thermodynamic parameters were determined at different ranges of temperature, in which negative values of ΔG° means the spontaneity in the adsorption process for both dyes and negative values for ΔH° for adsorption process of Reactive Blue 203 suggest the exothermic nature However the adsorption to the dye Reactive Red 195 ΔH° positive values suggest its endothermic nature. The values for ΔH° and the Ea for the adsorption of the two dyes in apple pomace show that they are of the same order of magnitude as the heat and the activation energy of chemisorption. The apple pomace was highly favorable for the adsorption of the dye Reactive Blue 203 and Reactive Red 195.
264

Tratamento eletroquímico e físico-químico para efluente de lavanderia industrial têxtil

Gonçalves, Leandro Vicente 26 March 2015 (has links)
CAPES / A lavanderia industrial têxtil é caracterizada pela variedade dos processos aplicados, pelo alto volume de efluentes gerados e pela carga poluidora. A caracterização física e química destes efluentes é de suma importância para determinação do tratamento apropriado, bem como para avaliação dos agentes poluentes e seus impactos potenciais. Desta forma, o desenvolvimento do presente estudo permite o aperfeiçoamento do conhecimento acerca dos processos eletroquímicos e físico-químico para a remoção de cor e carga orgânica em efluentes de lavanderia industrial têxtil. Os experimentos foram realizados em quatro processos: - 1: ensaios de eletrocoagulação / eletrofloculação / eletroflotação utilizando reator em escala de laboratório tipo tanque agitado, com o emprego de eletrodos de alumínio e carbono. - 2: ensaios físico-químicos utilizando o processo de flotação por ar dissolvido (FAD) em unidade de escala de bancada (flotateste) com o uso de tanino “Tanfloc SG”. - 3: ensaios FAD com o uso de policloreto de alumínio (PAC) e polímero aniônico. - 4: ensaios FAD com o uso de sementes de Moringa Oleífera. A metodologia utilizada para os ensaios de todos os processos foram o planejamento experimental do delineamento composto central rotacional DCCR com dois parâmetros avaliados para cada processo: - 1: corrente elétrica, e tempo de eletrocoagulação; - 2: dosagem de coagulante tanino e pH da solução; - 3: dosagem de coagulantes PAC e polímero aniônico; - 4: dosagem de coagulante moringa e pH da solução. Após o término dos ensaios, amostras do efluente tratado foram analisadas para determinação da eficiência de remoção das variáveis cor aparente, turbidez, demanda química de oxigênio (DQO) e sólidos suspensos totais (SST). No processo 1, o eletroquímico foi obtido uma eficiência ótima para a remoção de cor aparente, turbidez, DQO e SST de 86%; 58,93%; 75,2% e 66,3%, respectivamente. Para os ensaios FAD, a eficiência máxima para a remoção de cor aparente, turbidez, DQO e SST foi de 90%; 96,90%; 61,4% e 94,1%, respectivamente, para o processo 2, de 93%; 93,65%; 71,8% e 88,8%, respectivamente, para o processo 3, e de 65%; 80,00%; 40,2% e 62,3%, respectivamente, para o processo 4. Os resultados obtidos indicaram que apenas o experimento utilizando o processo FAD com o coagulante moringa oleífera não foi uma opção viável por ultrapassar o padrão de qualidade da variável cor aparente exigido pela a resolução CONAMA 357. Os demais processos e coagulantes estudados neste trabalho podem ser utilizados como alternativas tecnicamente viáveis para a remoção de cor aparente, turbidez, DQO e SST de efluentes de lavanderia têxtil. / The textile industrial laundry is characterized by the variety of existing processes, the large volume of wastewater and high polluting load. Physical and chemical characterization of these effluents is important to determine the appropriate treatment and to assess pollutants and their potential impacts. Thus, the development of this study allows contribute to the knowledge of the electrochemical processes and physical chemistry in order to remove the color and organic load in textile industrial laundry wastewater. The experiments were performed in four processes: - 1: electrocoagulation / electroflocculation / electrocoagulation tests using reactor at laboratory scale stirred tank with the use of aluminum and carbon electrodes. - 2: physico-chemical tests using process by dissolved air flotation (DAF) with a bench scale unit (flotatest) using tannin "Tanfloc SG". - 3: tests DAF using polyaluminum chloride (PAC) and anionic polymer. - 4: tests DAF using seeds of Moringa oleífera. The methodology used for the testing of all processes was the experimental design central composite rotational design (RCCD) with two parameters assessed for each process: - 1: electric current and electrocoagulation time; - 2: tannin dosage as coagulant and pH solution; - 3: PAC dosage as coagulant and anionic polymer; - 4: moringa dosage as coagulant and pH solution. At the end of the tests, samples of treated wastewater were analyzed to determine the removal efficiency of apparent color, turbidity, chemical oxygen demand (COD) and total suspended solids (TSS). In the process 1, optimal efficiency the electrochemical of process for the removal of apparent color, turbidity, COD and TSS 86%; 58.93%; 75.2% and 66.3%, respectively. For the DAF tests, the maximum efficiency for the removal of apparent color, turbidity, COD and TSS for process 2 was 90%; 96.90%; 61.4% and 94.1%, respectively, for process 3 was 93%; 93.65%; 71.8% and 88.8%, respectively; and for process 4 was 65%; 80.00%; 40.2% and 62.3%, respectively. The results indicated that only the experiment using the DAF process with the moringa oleífera coagulant was not a viable option, because it exceeds the quality standard of the apparent color required by the resolution CONAMA 357. The processes and coagulants studied in this work can be used as technically feasible alternatives to removal apparent color, turbidity, COD and TSS of textile industrial laundry wastewater.
265

Remoção dos corantes têxteis C.I. Reactive Blue 203 e C.I. Reactive Red 195 mediante o uso de bagaço de maçã como adsorvente

Marin, Sandra Liliana Albornoz 07 August 2015 (has links)
CNPq / A indústria têxtil tem grande impacto ambiental devido ao seu amplo consumo de água e da utilização de diferentes produtos químicos orgânicos como os corantes. Existem diferentes métodos utilizados no tratamento de efluentes têxteis, sendo um deles, a adsorção. A utilização de resíduos agroindustriais como adsorventes é uma alternativa para a descontaminação de efluentes com corantes. Desta forma, este trabalho teve por objetivo avaliar o resíduo agroindustrial de Bagaço de Maçã da variedade Fuji, proveniente da produção de sucos, como adsorvente alternativo na remoção de corantes têxteis C.I. Reactive Blue 203 e C.I. Reactive Red 195 em meio aquoso sintético. As características do adsorvente mostraram que o bagaço de maçã apresenta 89,36% de umidade, 35,64% de fibra bruta e a 52,72% de carbono. O pH(pcz) é de 3,5 e em sua superfície predomina sítios ácidos. Na espectroscopia do infravermelho observou-se a presença dos principais grupos funcionais (–OH), (–NH), (CH2), (–CO), (–C–O–), na microscopia eletrônica de varredura a morfologia da superfície do bagaço de maçã mostrou-se porosa e a determinação das características texturais indicaram uma área superficial de 2,088 (m2.g-1) para o tamanho de partícula de 0,125 mm. A partir dos resultados do planejamento experimental - 23, pode-se otimizar o processo de adsorção para os dois corantes pelo bagaço de maçã fixando as variáveis independentes com influência significativa (pH de 2,0 e granulometria do adsorvente em 0,125 mm). No estudo cinético o tempo de equilíbrio para o Reactive Blue 203 foi de 420 minutos e para Reactive Red 195 de 180 minutos e o ajuste matemático para ambos corantes foi para o modelo de pseudo-segunda ordem. As isotermas de equilíbrio foram testadas pelos modelos das isotermas de adsorção de Langmuir, Freundlich, Dubinin-Raduskevich e BET, sendo este último mais adequado para a descrição do processo. Os parâmetros termodinâmicos foram determinados em diferentes faixas de temperatura, em que valores negativos de ΔG° indicam a espontaneidade do processo de adsorção para os dois corantes e valores negativos para ΔH° no processo de adsorção do corante Reactive Blue 203 indicam natureza exotérmica no entanto para adsorção do corante Reactive Red 195 valores positivos de ΔH° sugerem a sua natureza endotérmica. Os valores de ΔH e Ea para a adsorção dos dois corantes em bagaço de maçã mostram que são da mesma ordem de grandeza que o calor e a energia de ativação da quimissorção. O bagaço de maçã mostrou-se altamente favorável para o processo de adsorção dos corantes Reactive Blue 203 e Reactive Red 195. / The textile industry has a big environmental impact because consume a lot of water, and use different chemical organic products like dyes. There are different methods for treatment of textile effluents one of those is adsorption. Using agroindustrial residues like adsorbents is an alternative for decontamination effluents by dyes. Therefore, this present work aimed to evaluate agroindustrial residue apple pomace of Fuji variety, that proceed of production of juices, like alternative adsorbent for the removal textile dyes C.I. Reactive Blue 203 and C.I. Reactive Red 195 in aqueous synthetic medium. The adsorbent characteristics showed that apple pomace present 89.36% of humidity and 35,64% of crude fiber. and 52,72% of C. The pH (pzc) is 3,5, and its surface prevails sites acids. In infrared spectroscopy it was observed the presence of the major functional groups (–OH), (–NH), (CH2), (–CO), (–C–O–). In scanning electron microscopy of the surface morphology of the apple pomace was found to be porous and determining the textural features indicated a surface area of 2,088 (m2.g-1) to 0,125 mm particle size. From the results of the experimental design 23 can optimize the process of adsorption of for both dyes by apple pomace, setting the independent variables with significant influence (pH of 2.0 and particle size of the adsorbent 0.125 mm). In the kinetic study the equilibrium time for Reactive Blue 203 was 420 minutes and for Reactive Red 195 was 180 minutes and for both dyes mathematical adjustment was to model the pseudo-second order. The equilibrium isotherms were tested by the models adsorption isotherms of Langmuir, Freundlich, Dubinin-Raduskevich and BET, the last being more suitable for the description of the process. The thermodynamic parameters were determined at different ranges of temperature, in which negative values of ΔG° means the spontaneity in the adsorption process for both dyes and negative values for ΔH° for adsorption process of Reactive Blue 203 suggest the exothermic nature However the adsorption to the dye Reactive Red 195 ΔH° positive values suggest its endothermic nature. The values for ΔH° and the Ea for the adsorption of the two dyes in apple pomace show that they are of the same order of magnitude as the heat and the activation energy of chemisorption. The apple pomace was highly favorable for the adsorption of the dye Reactive Blue 203 and Reactive Red 195.
266

Corantes naturais das cascas das árvores Stryphnodendron adstringens (Mart.) Coville e Croton urucurana Baill., nativas do Brasil: extração, tingimento, solidez de cor e caracterização do efluente / Natural dyes from trees barks Stryphnodendron adstringens (Mart.) Coville and Croton urucurana Baill., native to Brazil: extraction, dyeing, color fastness and wastewater characterization

Patrícia Muniz dos Santos Silva 27 September 2018 (has links)
Esse trabalho objetivou investigar o potencial dos extratos aquosos das cascas de barbatimão (Stryphnodendron adstringens (Mart.) Coville) e sangra dágua (Croton urucurana Baill.) como corante natural têxtil. Os extratos foram caracterizados quanto ao pH, o teor de sólidos totais e a estabilidade no armazenamento. Os extratos foram liofilizados e avaliados por espectroscopia no infravermelho com transformada de Fourier (FTIR), termogravimetria (TG) e calorimetria exploratória diferencial (DSC). Foram realizados experimentos preliminares de tingimento em tecidos multifibra e em diferentes concentrações dos extratos. A partir desses experimentos, foram definidas as variáveis temperatura, tempo e concentração do extrato para o estudo do tingimento por planejamento experimental 2³, em tecidos 100 % algodão e 100 % lã. Os tecidos tingidos em condição otimizada, sem e com mordentes metálicos, foram avaliados quanto à cor, a solidez de cor à luz, à lavagem, à fricção e ao suor. Os efluentes foram coletados e caracterizados quanto ao pH, turbidez, sólidos totais dissolvidos (STD), oxigênio dissolvido, demanda bioquímica de oxigênio (DBO), demanda química de oxigênio (DQO) e teores de ferro e alumínio dissolvidos. Foram conduzidos ensaios bacteriológicos nos extratos aquosos, etanólicos e liofilizados e nos tecidos tingidos. Os resultados das análises por FTIR indicaram a presença de taninos, lignina e celulose nos extratos. Pelo estudo de estabilidade os extratos possuem duração de 42 dias. Nas análises por TG, os extratos obtiveram perda de massa total similares e não geraram alteração na degradação dos tecidos tingidos. Na análise por DSC os extratos obtiveram picos endotérmico e exotérmixo em temperaturas próximas. As melhores condições para o tingimento dos tecidos avaliados é em 98 °C, por 60 min e na concentração de 100 % do extrato. A solidez de cor dos tecidos tingidos variou de baixa a excelente. Os extratos liofilizados apresentaram propriedades antibacterianas. Os efluentes apresentaram valores de STD, DBO, DQO e alumínio e ferro dissolvidos acima dos limites determinados pela legislação nacional. De modo geral, os resultados obtidos indicam que os extratos das cascas de barbatimão e sangra dágua são promissores para serem utilizados como corantes naturais têxteis / This research aimed to investigate the potential of aqueous extracts of barbatimão (Stryphnodendron adstringens (Mart.) Coville) and sangra dágua (Croton urucurana Baill.) bark as natural textile dyes. The extracts were characterized for pH, total solids content and storage stability. The extracts were lyophilized and evaluated by Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG) and differential scanning calorimetry (DSC). Preliminary dyeing experiments were carried out on multifiber fabrics and at different extracts concentrations. From these experiments, the variables temperature, time and concentration of the extract for the study of dyeing by experimental design 2³ in 100 % cotton and 100 % wool fabrics were defined. Fabrics dyed in optimized condition, using metal mordants and with no mordents, were evaluated by colorimetry, color fastness to light, wash, rubbing and perspiration. The effluents were collected and characterized by pH, turbidity, total dissolved solids (TDS), dissolved oxygen, biochemical oxygen demand (BOD), chemical oxygen demand (COD) and dissolved iron and aluminum contents. Bacteriological tests were conducted on aqueous, ethanolic and lyophilized extracts and on dyed fabrics. The results of the FTIR analysis indicated the presence of tannins, lignin and cellulose in the extracts. By the stability study were found that the extracts have a duration of 42 days. In the TG analyzes, the extracts obtained similar total mass loss and did not generate alteration in the degradation of the dyed fabrics. In the DSC analysis the extracts obtained endothermic and exotherm peaks at near temperatures. The optimized dyeing for the evaluated fabrics is at 98 °C for 60 min and at the concentration of 100 % of the extract. The color fastness of the dyed fabrics ranged from low to excellent. Lyophilized extracts showed antibacterial properties. The wastewater showed values of TDS, BOD, COD and aluminum and iron dissolved above the limits determined by national legislation. In general, the results indicate that barbatimão and sangra dágua extracts are promising for use as natural textile dyes
267

Estudo do potencial de uso do resíduo efluente gerado da destilação do óleo de folhas de eucalipto (Corymbia citriodora (Hook) Pryor e Johnson 1976), como corante natural para o tingimento têxtil de algodão / Study of the potential of using waste effluent from the distillation of the leaf oil of eucalyptus (Corymbia citriodora (Hook) Pryor and Johnson 1976), as a natural dyestuff for dyeing cotton fabrics

Ticiane Rossi 23 February 2010 (has links)
Atualmente, os corantes naturais vêm ganhando maior interesse da sociedade, fazendo crescer um novo nicho de mercado, que valoriza produtos obtidos de matériasprimas naturais, devido aos menores danos causados à saúde humana e ao meio ambiente. Uma fonte potencial para obtenção de corantes encontra-se na operação industrial da obtenção de óleo essencial de folhas de eucalipto. Trata-se de um resíduo líquido gerado na etapa de destilação das folhas, mediante o emprego de vapor d´água. Um grande volume de extrato é gerado e descartado como efluente do processo. O Brasil é um dos principais produtores mundiais de óleo de folhas de eucalipto, sobretudo de Corymbia citriodora (ex Eucalyptus citriodora), havendo, desse modo, importante potencial de exploração do efluente gerado na destilação das folhas como matéria-prima. Contando com o apoio de uma empresa do setor de produção desse óleo, pretendeu-se avaliar o potencial desse extrato como corante natural, visando o tingimento de tecidos de algodão. Para caracterização do resíduo efluente e do corante natural dele obtido, foram realizadas avaliações físicas e químicas, tais como: teor de sólidos, pH, densidade, teor de taninos condensados e medição de cor mediante análises espectrofotométricas. Na avaliação do potencial do resíduo efluente como corante natural, foi realizado um estudo para determinação do método de tingimento de tecidos de algodão, através de diversos tratamentos que incluíram a alteração das variáveis de temperatura, tempo e concentração do corante natural. Nos tecidos tingidos, foi avaliada a solidez de cor à luz de arco de xenônio e à lavagem, através das normas da ABNT da CB 17 - Têxteis e Vestuário. O resíduo efluente e o corante natural apresentaram ambos pH ácido, teor de sólidos totais de 3,4 e 48,1 e teor de taninos condensados de 0,6 e 10,9 %, respectivamente. Em relação à cor dos extratos, ambos refletem a cor marrom. O resíduo efluente possui maiores valores de L*, a* e b* que o corante natural, e este aproxima-se da cor preta, devido aos valores de a* e b* serem próximos a zero. Os resultados obtidos no processo para a determinacao do método de tingimento, apresentaram uma grande variação entre os tratamentos propostos. A propriedade que mais variou nas cores dos tecidos tingidos foi o L*. Os valores de E* também variaram entre os tratamentos, sendo que, apenas o tratamento 9 foi considerado similar à referência 8, para essa propriedade. No tocante aos resultados de solidez de lavagem, as notas de alteração de cor foram de 3-4 para ambas as concentrações de corante nos tecidos tingidos. O manchamento do tecido multifibras foi, em geral, maior que 4 para ambas as concentrações. Para solidez de cor à luz, os tecidos tingidos tiveram alteração na ordem de 2-3 e 3, para concentração de 10% e 50 %, respectivamente. Em geral, os resultados de solidez demonstraram que o corante natural atingiu notas aceitáveis à industria têxtil e que o corante natural obtido a partir do resíduo efluente de folhas de C. citriodora possui potencial de uso no tingimento de algodão. / Currently, natural dyes are gaining interest in the society, creating a new market niche that values products obtained from natural raw materials, due to less damage to human health and the environment. A potential source for obtaining dye lies in industrial operation to obtain essential oil from eucalyptus leaves. It is a liquid waste generated in the distillation of the leaves, using water steam. A large volume of extract is generated and disposed as effluent of the process. Brazil is one of the worlds main producers of oil from eucalyptus leaves, especially Corymbia citriodora (formerly Eucalyptus), and there is, thus, significant potential for exploration of the effluent generated in the distillation of the leaves as raw material. With the support of a company in the oil production, it aimed to evaluate the potential of this extract as a natural dye, aiming at dyeing cotton. The characterization of waste effluent and natural dyestuff obtained was evaluated in terms of physical and chemical properties, such as total solids content, pH, density, condensed tannins content and color measurement by spectrophotometric analysis. In assessing the potential of the waste effluent as a natural dye, a study was conducted to determine the method of dyeing cotton, through various treatments which included changing variables such as temperature, time and concentration of natural dyestuff. In the dyed fabrics, it was evaluated the fastness properties of color in the light of a xenon arc and washing through the norms of the ABNT CB 17 - Textiles and Clothing. Both the waste effluent and the natural dyestuff presented an acid pH, total solids content of 3.4% and 48.1% and condensed tannin content of 0.6% and 10.9% respectively. Regarding the color of the extracts, both shown the brown color. The waste effluent had higher values of L*, a* b* than the natural dyestuff, and this was approximately to the black color, because the values of L*, a* b* were close to zero. The property with the larger variation in the colors of dyed fabrics was the L*. The values of E* also varied between treatments, with only treatment 9 was considered similar to reference 8, for this property. Concerning the results of washing fastness, the notes of color change were 3-4 for both concentrations of dye in dyed fabrics. The staining of the multi-fiber fabric was generally greater than 4 for both concentrations. For color fastness properties in light, dyed fabrics have the notes changed in the order of 2-3 and 3 for the concentrations 10% and 50%, respectively. In general, solidity results showed that natural dyestuff reached the acceptable notes for textile industry and the natural dyestuff obtained from waste effluent leaves of C. citriodora has a potential use as natural dyestuff in dyeing cotton.
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Simulação da difusão de corantes reativos em fibras de algodão / Diffusion simulation of reactive dyes in cotton fibers

Vidart, Jacyara Moreira Martins, 1988- 23 August 2018 (has links)
Orientador: Sergio Persio Ravagnani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T09:44:58Z (GMT). No. of bitstreams: 1 Vidart_JacyaraMoreiraMartins_M.pdf: 1450834 bytes, checksum: c65e1c601aa075737a3b6a8f596ef8c4 (MD5) Previous issue date: 2013 / Resumo: O processo de tingimento empregado nas indústrias têxteis é de fundamental importância para o setor. A fim de garantir a satisfação dos consumidores, com produtos de boa solidez e uniformidade de cor, é necessário que o corante utilizado no processo de tingimento apresente alta afinidade com as fibras. Além da cobrança por parte dos consumidores em relação a produtos de alta qualidade, o setor têxtil enfrenta rígidas normas ambientais relacionadas ao lançamento de seus efluentes altamente tóxicos. Desta forma, a escolha de corantes e fibras com maior afinidade entre si se faz necessária para menor geração de resíduos, pois um tingimento com maior afinidade necessita de menor quantidade de auxiliares de tingimento e menor consumo de água. Conhecendo-se a difusividade de um corante em uma fibra, pode-se determinar a afinidade entre eles e, consequentemente, otimizar o processo de tingimento, escolhendo corantes com maior difusividade. Neste trabalho, buscou-se determinar os coeficientes de difusividade de corantes reativos Cosmos Bezaktiv S-C no tingimento de fibras de algodão. Para tanto, ensaios experimentais de tingimento foram realizados e, dados referentes à concentração de corante remanescente no banho de tingimento foram coletados. A partir dos dados obtidos experimentalmente, foi possível realizar a simulação computacional baseada na lei de difusividade de Fick para a determinação dos coeficientes de difusão dos corantes estudados. Os resultados mostraram que o modelo de difusão de Fick é adequado para a representação experimental do tingimento empregado. Além disso, os corantes Cosmos Bezaktiv S-C apresentaram alta difusividade nas fibras de algodão, sendo portanto, excelentes para este tipo de tingimento / Abstract: The dyeing process used in textile industries is very important to the sector. In order to guarantee the satisfaction of consumers with products of good color uniformity and strength, it is required that the dye used in the dyeing process has high affinity with the fibers. Besides collecting from consumers in relation to high-quality products, the textile sector is facing strict environmental standards related to the launch of its wastewaters highly toxic. Thus, the choice of dyes and fibers with higher affinity between them is required to generate less waste, since a dye with a higher affinity require fewer dyeing auxiliaries and lower water consumption. Knowing the diffusivity of a dye in a fiber, can be determine the affinity between them, and consequently optimize the dyeing process, by selecting dyes with higher diffusivity. In this study, we sought to determine the coefficients of diffusivity of reactive dyes Cosmos Bezaktiv S-C in dyeing of cotton fibers. To this end, experimental tests were carried out dyeing and data relating to the concentration of dye remaining in the dyebath was collected. From the experimental data, it was possible to carry out computer simulation based on Fick's law diffusivity for the determination of diffusion coefficients of the dyes studied. The results showed that the Fick's diffusion model is suitable for dyeing representation of experimental employed. In addition, the dyes Cosmos Bezaktiv S-C showed high diffusivity in cotton fibers, and therefore excellent for this kind of dyeing / Mestrado / Ciencia e Tecnologia de Materiais / Mestra em Engenharia Química
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Hydrogenases from sulphate reducing bacteria and their role in the bioremediation of textile effluent

Mutambanengwe, Cecil Clifford Zvandada January 2007 (has links)
The continuing industrial development has led to a corresponding increase in the amount of waste water generation leading to a consequential decline in levels and quality of the natural water in the ecosystem. Textile industries consume over 7 x 10[superscript 5] tons of dyes annually and use up to 1 litre of water per kg of dye processed and are third largest polluters in the world, the problem being aggravated by the inefficiencies of the dye houses. An abundance of physio-chemical methods are in use world wide, however, there is increasing concern as to their impact in effectively treating textile effluents as they introduce secondary pollutants during the ‘remediation’ process which are quite costly to run, maintain and clean up. Research on biological treatment has offered simple and cost effective ways of bioremediating textile effluents. While aerobic treatment of textile dyes and their effluents has been reported, its major draw back is commercial up-scaling and as such anaerobic systems have been investigated and shown to degrade azo dyes, which form the bulk of the dyes used world wide. However, the mechanisms involved in the bioremediation of these dyes are poorly understood. The aims of this study were to identify and investigate the role of enzymes produced by sulphate reducing bacteria (SRB) in bioremediating textile dye and their effluents. Sulphate reducing bacteria were used in this study because they are tolerant to harsh environmental conditions and inhibit the proliferance of pathogenic micro-organisms. The appearance of clear zones in agar plates containing azo dye concentrations ranging from 10 – 100 mgl[superscript -1] showed the ability of SRB to decolourize dyes under anaerobic conditions. Assays of enzymes previously reported to decolourise azo dyes were not successful, but led to the identification of hydrogenase enzyme being produced by SRB. The enzyme was found to be localised in the membrane and cytoplasm. A surface response method was used to optimize the extraction of the enzyme from the bacterial cells resulting in approximately 3 fold increase in hydrogenase activity. Maximum hydrogenase activity was found to occur after six days in the absence of dyes but was found to occur after one day in the presence of azo dyes. A decline in hydrogenase activity thereafter, suggested inhibition of enzymatic activity by the putative aromatic amines produced after azo cleavage. Purification of the hydrogenase by freeze drying, poly ethylene glycol, and Sephacryl – 200 size exclusion- ion exchange chromatography revealed the enzyme to have a molecular weight of 38.5 kDa when analyzed by a 12 % SDS-PAGE. Characterisation of the enzyme revealed optimal activity at a pH of 7.5 and temperature of 40 °C while it exhibited a poor thermal stability with a half-life of 32 minutes. The kinetic parameters V[subscript max] and K[subscript m] were 21.18 U ml[superscript -1} and 4.57 mM respectively. Application of the cell free extract on commercial dyes was not successful, and only whole SRB cells resulted in decolourisation of the dyes. Consequently trials on the industrial dyes and effluents were carried out with whole cells. Decolourisation rates of up to 96 % were achieved for the commercial dyes and up to 93 % for the industrial dyes over a period of 10 days.
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Environmentally friendly dyeing and finishing

Dayla, Mackraj January 2013 (has links)
The textile industry in South Africa is a significant contributor to the chemical load that public wastewater treatment plants have to process, and the discharge of toxic substances, especially to the aquatic environment. In order to address this issue at factory level, the processes at a textile plant, JMV Textiles were chosen for investigation into the possibilities of minimization of discharges of harmful substances into the environment. The study followed the principles of cleaner production, and the processes that were investigated and revised were: The conventional peroxide bleaching process employed a peroxide stabilizer that did not biodegrade easily. The bleaching process was changed, so that the prevailing conditions in the fabric and dyebath facilitated bleaching without the addition of peroxide stabilizer, and also reduced the alkali and energy requirements. Polyester‐viscose fabric was pretreated by bleaching with hydrogen peroxide, which seemed to be unnecessarily rigorous, because polyester and viscose, unlike natural fibres, are relatively clean and have good whiteness in comparison with natural fibres. The proposed alternate pretreatment was a scour with detergent and alkali. The pretreatment for all polyester‐cotton fabrics was also a hydrogen peroxide bleach. Due to the ability of medium and dark shades to mask the natural tint of cotton fibres, a simpler alternate pretreatment, consisting of an alkaline scour with sequestering agent, was trialled. An unacceptable proportion of the dyeings on polyester was rejected for dye‐stains and dye‐marks. A possible solution exploited the properties of using the finishing auxiliary chemical to alleviate dye‐stains and dye‐marks during the dyeing stage, instead of using the chemical after dyeing. The highly toxic carrier that was used to facilitate level dyeing of polyester fibres that had unacceptable variation in their dyeing properties, was replaced by a less toxic carrier. The formulation for dyeing polyester was simplified to eliminate the auxiliary chemicals that were not essential to the dyeing process. Pale reactive dyed shades on cellulose and polyester‐cellulose were washed off only with hot water instead of detergent. The revised procedures consequential to the study, offered significant environmental benefits by reducing the concentration and volume of effluent produced, substituting a highly toxic carrier with a less toxic one and saving energy and water. Implementation of the suggested changes also offered financial benefits. The management of the factory, however, accepted and implemented some changes, but wanted further investigations for others and a phased approach to the other suggested changes.

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