CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The high consumption of green coconut water has generated increasing in the residue caused by improper discard of green coconut rind in Brazilian coast. To reduce this problem, Embrapa Tropical Agroindustry installed a Pilot Unit processing of green coconut rind to obtain fiber and powder, which ends up generating an effluent with high organic load, high sugar and polyphenols content and is called liquid of the rind of green coconut (LCCV). In order to reduce polyphenols and sugar content, alcoholic fermentation was carried out in the effluent, with 5 and 7.5% (w/v) of Saccharomyces cerevisiae, another fermentation with 5% (w/v) of S. cerevisiae wich was reused in subsequent fermentations and also polyphenols removal by adsorption using aluminum pillared clay. Phenolic compounds present in LCCV were characterized by nuclear magnetic resonance of hydrogen and liquid chromatography with mass spectrometry, it was possible to identify chlorogenic acid, isomers of caffeoyl shikimic acid, including 5-O-caffeoylshikimic acid, which is the major phenolic compound of LCCV and also, ferulic acid. LCCV total polyphenols levels were reduced by fermentation of 7769.1 mg/L to 3808.6 mg/L in the fermentation with 5% (w/v) yeast and 2892.4 mg/L in the fermentation 7,5% (w/v) yeast. In the fermentation with reuse of yeast, the reduction in polyphenols content ranged of 4084.7 to 5853.5 mg/L. The fermentation was efficient in reducing the polyphenols levels, in addition its efficacy to consume the sugars, glucose and fructose, present in LCCV. / O consumo de Ãgua de coco verde tem gerado um aumento nos resÃduos provocado pelo descarte inadequado da casca de coco verde no litoral brasileiro. A fim de minimizar esse problema, a Embrapa AgroindÃstria Tropical instalou uma unidade piloto de beneficiamento da casca de coco verde para obtenÃÃo de fibra e pÃ, o que acaba gerando um efluente com carga orgÃnica elevada, alto teor de aÃÃcar e de polifenÃis e à denominado de lÃquido da casca de coco verde (LCCV). A fim de se reduzir o teor de polifenÃis totais, foi realizada uma fermentaÃÃo alcoÃlica do efluente, com 5 e 7,5% (p/v) de Saccharomyces cerevisiae, com 5% (p/v) de S. cerevisiae que foi reutilizada fermentaÃÃes posteriores, alÃm da remoÃÃo por adsorÃÃo de polifenÃis do LCCV utilizando argila pilarizada de alumÃnio. Os compostos fenÃlicos presentes no LCCV foram caracterizados atravÃs de ressonÃncia magnÃtica nuclear de hidrogÃnio e cromatografia lÃquida acoplada à espectrometria de massa, onde foi possÃvel identificar o Ãcido clorogÃnico, isÃmeros do Ãcido cafeoil chiquÃmico, entre eles o Ãcido 5-O-cafeoil chiquÃmico, que à o composto fenÃlico majoritÃrio do LCCV e Ãcido ferÃlico. A fermentaÃÃo reduziu os teores de polifenÃis totais do LCCV, passando de 7769,1 mg/L a 3808,6 mg/L com a fermentaÃÃo com 5% (p/v) de levedura e para 2892,4 mg/L com a fermentaÃÃo com 7,5% (p/v) de levedura. Para a fermentaÃÃo com reutilizaÃÃo de levedura, a reduÃÃo na concentraÃÃo de polifenÃis variou de 4084,7 a 5853,5 mg/L. A fermentaÃÃo foi eficiente na reduÃÃo dos teores dos polifenÃis e no consumo dos aÃÃcares glicose e frutose presentes no LCCV.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Os corantes sintÃticos sÃo um dos poluentes mais comuns e frequentemente encontrados na indÃstria tÃxtil. A destinaÃÃo de esgoto contendo corantes para corpos de Ãgua à extremamente importante do ponto de vista ambiental, jà que mesmo em baixas concentraÃÃes os corantes podem ser altamente tÃxicos para sistemas aquÃticos. A elevada toxicidade à um dos grandes problemas de Ãguas residuais contendo corantes. Este estudo examinou como adsorventes nanoporosos trÃs materiais sendo um HidrÃxido Duplo Lamelar (HDL â Mg/Al), uma argila pilarizada (Al-PILC) e um carbono ativado comercial (GAC-Norit 1240) avaliando seus comportamentos na remoÃÃo dos corantes Reativo Preto 5 (RP5), Azul de Metileno (AM) e Ãcido Azul 25 (AA25). Os materiais baseados em argilas naturais e sintetizadas em laboratÃrio, assim como o carbono ativado, foram caracterizados por difraÃÃo de raios X, BET e FTIR, a fim de se obter informaÃÃo sobre suas caracteristicas estruturais e texturais. Experimentos em batelada utilizando um sistema de tanques agitados foram realizados para averiguar o efeito do pH do meio, da concentraÃÃo inicial de corante, do tempo de contato e da forÃa iÃnica do meio na adsorÃÃo dos corantes. Para o sistema de tanques agitados foram utilizados um agitador rotatÃrio orbital e tubos de acrÃlico contendo 20 mL de soluÃÃes de corantes em contato com 0,015 g dos adsorventes. As concentraÃÃes de equilÃbrio de cada corante foram determinadas em espectrofotÃmetro UV/Vis. A fim de descrever o comportamento das isotermas de adsorÃÃo, os dados de equilÃbrio foram correlacionados com o modelo de Langmuir (L). A contribuiÃÃo dos parÃmetros de transferÃncia de massa na cinÃtica de adsorÃÃo dos corantes RP5, AA25 e AM em carbono ativado tambÃm foi investigada. Estes dados fundamentais forneceram uma melhor compreensÃo dos mecanismos de transferÃncia de massa e dinÃmica difusional do sistema. O comportamento do pH e da forÃa iÃnica do meio foi de suma importÃncia para o entendimento dos processos de adsorÃÃo nos respectivos materiais para cada corante analisado. O pH das soluÃÃes aquosas foi bastante diferenciado, o qual foi dependente das caracterÃsitcas aniÃnicas e catiÃnicas dos materiais e dos corantes. De acordo com a anÃlise estatÃstica, o modelo de Langmuir foi adequado para representar os dados de adsorÃÃo dos corantes comprovado pela combinaÃÃo das constantes de ligaÃÃo do modelo, evidenciando uma forte interaÃÃo adsorvente-adsorbato. Pode-se notar que as cinÃticas de adsorÃÃo de corantes seguem um comportamento semelhante, com uma queda brusca da concentraÃÃo inicial de corante no sobrenadante nos primeiros momentos de contato, atingindo o equilÃbrio em aproximadamente 60 minutos, do que se pode inferir uma difusÃo molecular intrapartÃcula. As quantidades adsorvidas dos trÃs materiais indicaram um melhor desempenho obtido para o carbono ativado. / Synthetic dyes are one of the most common pollutants and often found in the textile industry. The disposal of wastewater containing dyes on water bodies is extremely important from an environmental standpoint, since the dyes even at low concentrations can be highly toxic to aquatic systems. The high stability and toxicity are the major problem in the treatment of wastewater containing dyes. This study examined three nanoporous adsorbents materials: a lamellar double hydroxide (LDH-Mg/Al), pillared clay (Al-PILC) and a commercial activated carbon (Norit GAC-1240), assessing hair performance in the removal of dyes Reactive Black 5 (RB5), Methylene Blue (MB) and Acid Blue 25 (AB25) used in the textile industry. The materials based on natural clays synthesized in the laboratory, and activated carbons were characterized by XRD, BET and FTIR, in order to obtain information about their structural and textural characteristics. Experiments using a batch stirred tank system were performed to investigate the effect of pH, the initial concentration of dye, contact time and ionic strength through adsorption of the dyes. For the system of stirred tanks a rotary shaker and acrylic tubes were used containing 20 mL of dye solutions in contact with 0.015 g of adsorbent. The equilibrium concentration of each dye was determined with a spectrophotometer UV/Vis. In order to describe the behavior of adsorption isotherms, the equilibrium data were correlated with the Langmuir model (L). The contribution of mass transfer parameters on the kinetics of adsorption of dyes RP5, AB25 and MB on activated carbon was also investigated. These data provide a basic understanding of mechanisms of mass transfer and dynamic diffusional system. The behavior of pH and ionic strength of the medium was very important for understanding of adsorption processes in the respective materials for each dye examined. The pH of the aqueous solutions was greatly different, which was dependent on characteristics anionic and cationic materials and colorants. According to statistical analysis, the Langmuir model was adequate to represent the data of adsorption of dyes shown. It may be noted that the kinetics of adsorption of dyes follow a similar behavior, with a sharp drop of the dye initial concentration in the supernatant in the first moments of contact, reaching the equilibrium in approximately 100 minutes. The adsorbed amounts of the three materials showed a revealed better performance obtained for activated carbon.

Ces dernières années, les problèmes d’environnement et de dépollution sont devenus cruciaux. En particulier, les industries textiles sont une source très importante de pollution des milieux aquatiques. De 60 à 70 % des colorants de l’industrie textiles contiennent une ou plusieurs fonctions azoïques et sont pour la plupart d’entre eux toxiques, mutagènes et cancérigènes. L’objectif de la thèse a été d’évaluer l’efficacité du procédé photocatalytique pour éliminer des colorants anioniques et cationiques seuls ou en mélange en présence de dioxyde de titane et d’argile pontée au titane, synthétisé au laboratoire. Trois colorants sont étudiés comme modèle le bleu de Méthylène (BM), le noir Rémazol 5 (NR5) et le réactif rouge 2 (RR2). La première partie du travail est une étude cinétique de l’adsorption, de la dégradation et de la minéralisation de ces colorants à différents pH. Plusieurs conclusions émergent (1) l’isotherme d’adsorption n’est pas une isotherme de Langmuir (2) aucune corrélation n’est observée entre les quantités adsorbées et les vitesses de dégradation et (3) à forte concentration en colorants, une partie de la lumière est absorbée et la vitesse de dégradation diminue. La seconde partie du travail concerne l’étude du mélange des deux colorants anioniques. L’influence du rapport molaire, du pH et de la concentration initiale sur l’isotherme d’adsorption, la cinétique de décoloration et de minéralisation des deux colorants dans le mélange sont étudiés et comparés à celle obtenues pour les colorants pris individuellement. Aucun complexe n’est formé. Des compétitions entre les deux colorants sont observées après saturation de la surface de TiO2. Au-delà de la saturation du catalyseur un ralentissement de la minéralisation du COT et des hétéroatomes est observé. La troisième partie de l’étude est dédiée à l’étude de la préparation, caractérisation et propriétés photocatalytique de l’argile pontée au TiO2 (MMT-TiO2) et du matériau composite : argile pontée au TiO2 dopée avec de l’argent (MMT-TiO2/Ag). Cette étude est réalisée sur le colorant cationique (BM) et le colorant anionique (NR5). Une adsorption totale du colorant BM est observée, contrairement au NR5 qui ne s’adsorbe pratiquement pas, suggérant une adsorption par liaison ionique. L’argile pontée dopée ou non ne présente pas des propriétés photocatalytiques plus importantes que celle de TiO2 mais joue un rôle important sur l’adsorption des colorants cationiques, ce qui favorise leur élimination de la solution aqueuse. La présence d’Ag diminue les propriétés d’adsorption et de photocatalyse de l’argile pontée. / The problems of environment become crucial. In particular, textile industries are important sources of pollution of the aquatic system. 60% to 70% of dyes used in these textiles industries are azo dyes containing one or more; some of them are toxic, mutagenic and carcinogenic compounds. The aim was to evaluate the efficiency of photocatalytic processed for the elimination of anionic and cationic dyes alone or in combination with titanium dioxide and clay pillared with titanium, synthesized in the laboratory. The photocatalytic processing is interesting because solar flux can be used. Three dyes were studied as model: methylene blue (BM), black Remazol 5 (NR5) and reactive red 2 (RR2). The first part of this work is a kinetic study of adsorption, degradation and mineralization of these dyes at different pH. Several conclusions emerge (1) the adsorption isotherm is not of Langmuir type(2) no correlation exists between the quantities adsorbed and the degradation rates and (3) at high concentration, a part of UV is absorbed by the dye and the degradation rate decreases. The second part of the work involves the study of the mixture of two anionic dyes. The concentration of both dyes in the mixture, the influence of molar ratios, pH and initial concentration on the adsorption isotherm, kinetics of decolorization and mineralization of the two dyes in the mixture are compared to that obtained for the individual dyes. No complex is formed and competition between the two dyes occurs only after saturation of the photocatalyst surface. Beyond the saturation of the catalyst a slower mineralization of TOC and heteroatoms are observed. The third part deals with the preparation, characterization and photocatalytic properties of TiO2 pillared clay (MMT-TiO2) and of a composite material: TiO2 pillared clay doped with silver (MMT -TiO2/Ag), performed on the cationic dye (MB) and the anionic dye (NR5). A total adsorption of the BM dye is observed. Constrasting with the NR5 adsorption suggesting an adsorption by ionic bond. The pillared clay doped or not with silver but favors the elimination of dyes from the aqueous solution by adsorption. The presence of silver reduces the adsorption properties and photocatalysis properties of the pillared clay.