A princípio, foram realizados ensaios de enriquecimento em reatores em batelada, sob agitação, para avaliar a melhor condição nutricional, meio Beller ou meio Zinder, para crescimento microbiano e remoção de sulfato. Posteriormente, esta melhor condição nutricional foi usada para crescimento microbiano e remoção de etanol, tolueno e benzeno em ensaios contínuos em dois reatores anaeróbios horizontais de leito fixo (RAHLF), sob condições de redução de sulfato. Os sistemas foram inoculados com lodo de reator anaeróbio de fluxo ascendente e manta de lodo tratando águas residuárias provenientes de abatedouro de aves. Os RAHLF consistiram de biomassa imobilizada em espumas de poliuretano submetidas a concentrações de 91 e 550 mg/l de sulfato ferroso e sulfato de sódio, respectivamente, para promoção de ambiente sulfetogênico. Tolueno e benzeno foram adicionados, separadamente nos reatores, em concentrações iniciais de 2,0 mg/l, seguidas de aumentos que variaram até as concentrações finais de 9 e 10 mg/l, para tolueno e benzeno, respectivamente. O etanol foi adicionado em ambos reatores a concentração inicial de 170 mg/l, seguido de aumento de até 960 mg/l. Os reatores foram operados a 30 (± 2) ºC com tempo de detenção hidráulica de 12 h. A eficiência na remoção da matéria orgânica nos dois reatores foi próxima a 90% com taxa máxima de degradação de tolueno de 0,06 mg tolueno/mg ssv.d, e 0,07 mg benzeno/mg ssv.d, para benzeno. A redução de sulfato foi de 99,9% em todas as condições nutricionais nos dois reatores. A caracterização microscópica do biofilme revelou diversas morfologias e o perfil de DGGE mostrou variação nas populações de BRS e de representantes do Domínio Bacteria em geral, o que foi associado com as crescentes concentrações de tolueno e benzeno nos meios de alimentação. Finalmente, o presente trabalho demonstrou que unidades compactas de RAHLF, sob condições sulfetogênicas, oferecem alternativa para a biorremediação in situ de compostos aromáticos. / Previously, enrichment assays in batch reactors were used to evaluation of best nutritional condition, Beller or Zinder medium, to microorganism growth and sulfate removal. Further, the chosen nutritional condition was used in two horizontal-flow anaerobic immobilized biomass (HAIB) reactors under sulphate-reducing condition, which were exposed to different amounts of ethanol, toluene and benzene. The systems were inoculated with sludge taken from up-flow anaerobic sludge blanket (UASB) reactors treating refuses from a poultry slaughterhouse. The HAIB reactors comprised of an immobilized biomass on polyurethane foam and ferrous and sodium sulphate solutions were used (91 and 550 mg/L, respectively), to promote a sulphate-reducing environment. Toluene and benzene were added at an initial concentration of 2.0 mg/L followed by an increased range of different amendments. Ethanol was added at an initial concentration of 170 mg/L followed by an increased range of 960 mg/L. The reactors were operated at 30 (± 2) °C with hydraulic detention time of 12 h. Organic matter removal efficiency of 90%, in both systems, with a maximum toluene degradation rate of 0.06 mg toluene/mg vss.d and with a maximum benzene degradation rate of 0.07 mg benzene/mg vss.d. Sulfate reduction was dose to 99.9% for all-nutritional amendments in both systems. Biofilm microscopic characterization revealed a diversity of microbial morphologies and DGGE-profiling showed a variation of bacterial and sulphate reducing bacteria (SRB) populations, which were, significantly, associated with toluene and benzene amendments. Thus, this work demonstrates that compact units of HAIB reactors, under sulphate reducing conditions, are a potential alternative for in situ aromatic compounds bioremediation.

Orientador: Nelson Eduardo Duran Caballero / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-10T05:06:09Z (GMT). No. of bitstreams: 1 Donaire_PatriciaPulciniRosvald_D.pdf: 1368968 bytes, checksum: 36ddc25863076b787c4847f7b99b272a (MD5) Previous issue date: 2007 / Resumo: O presente trabalho trata do desenvolvimento de um reator tubular fotocatalítico aplicado ao tratamento de águas superficiais e subterrâneas contaminadas com compostos orgânicos voláteis, mais especificamente benzeno, tolueno, etilbenzeno e xileno (BTEX). O reator opera com recirculação da amostra e é constituído por dois catalisadores semicondutores, o dióxido de titânio e o dióxido de zircônio (TiO2/ZrO2). Estes catalisadores foram depositados sobre substratos de vidro na forma de filme misto e ativados com luz artificial proveniente de 2 lâmpadas de luz negra de 15 W cada, representando uma intensidade luminosa total de 3,6 mW cm. Os resultados demonstraram a viabilidade da utilização da fotocatálise heterogênea através da deposição de 15 camadas do filme misto sobre a matriz de vidro. A irradiação de água deionizada contaminada com 10 mg L de BTEX resultou em 95,9% de remoção destes compostos em pH 6,6 e vazão de recirculação de 280 mL min , onde somente o benzeno não alcançou o limite permitido pela legislação. A quantificação dos analitos foi realizada utilizando-se microextração em fase sólida (SPME). Observou-se uma cinética de pseudo-primeira ordem sendo a concentração inicial um fator limitante na taxa de degradação. A acetofenona foi a espécie intermediária detectada durante o processo fotocatalítico. No experimento de toxicidade utilizando Daphnia similis como organismo teste, a remoção de toxicidade foi atingida após 30 min de tratamento de água contaminada com gasolina onde o CE50-48 h inicial médio foi de 14,1% atingindo um CE50-48 h final médio de 84,3% / Abstract: The present work deals with the development of a photocatalytic tubular reactor to treat superficial and groundwaters contaminated with organic volatile compounds, more specifically benzene, toluene, ethylbenzene and xylene (BTEX). The reactor was operated with sample recirculation and it was constituted by two semiconductors catalysts, the titanium dioxide and the zirconium dioxide (TiO2/ZrO2). These catalysts were deposited over glass substrate in the form of mixed film and activated with artificial light originated from two 15 W black light lamps representing an average light intensity of 3.6 mW cm. The results showed the viability of heterogeneous photocatalysis using a deposition of 15 mixed film layers over the glass matrix. The photodegradation of deionized water contaminated with 10 mg L of BTEX gave a 95.9% of BTEX removal at pH 6.6 with a recirculation flow of 280 mL min . Among the other components of BTEX, only the benzene did not reach the permitted limit by legislation. The analytes were quantified by solid phase microextraction (SPME). The kinetic of pseudo-first order was observed and being the initial concentration a limiting factor in the degradation rate. The acetophenone was the intermediate species detected during photocatalytic process. In the toxicity experiment using Daphnia similis as organism test, the toxicity removal was reached after 30 min of treatment of contaminated water with gasoline where the initial average CE50-48 h was 14.1 % and reaching a final average CE50-48 h of the 84.3% / Doutorado / Quimica Analitica / Doutor em Quimica

O verapamil (VER) é um composto quiral comercializado como mistura racêmica dos enantiômeros (+)-(R)-VER e (-)-(S)-VER. O VER é biotransformado em norverapamil (NOR) e em outros metabólitos por vias dependentes do CYP. O tolueno e o n-hexano são solventes orgânicos que podem alterar o metabolismo de medicamentos dependente do CYP. Assim, o estudo investiga a estereosseletividade na farmacocinética do verapamil administrado a ratos na dose de 10 mg kg-1, sob forma racêmica, e do seu metabólito, norverapamil, bem como a influência do n-hexano e do tolueno na disposição cinética dos enantiômeros (+)-(R) e (-)-(S)-VER e (R)- e (S)-norverapamil em animais tratados com os solventes por inalação em câmara de exposição do tipo nose only nas concentrações de 88, 176 e 352 mg/m3 para o n-hexano e 94, 188 e 376 mg/m3 para o tolueno. Os enantiômeros do VER e do NOR foram separados na coluna de fase quiral Chiralpak® AD e analisados por LC-MS/MS (m/z = 441,3->165,5 para os enantiômeros do norverapamil e m/z 455,3->165,5 para os enantiômeros do verapamil). A análise farmacocinética foi realizada com base no modelo monocompartimental. A farmacocinética do verapamil é estereosseletiva em ratos do grupo controle não tratado com os solventes com acúmulo plasmático do eutômero (-)-(S)-VER (AUC0-? = 250,8 vs 120,4 ng mL-1 h; P<=0,05, teste de Wilcoxon). O metabólito (S)-NOR também foi acumulado no plasma dos animais do grupo controle com razão S/R relativa ao parâmetro AUC0-? de 1,5. Os parâmetros farmacocinéticos AUC0-?, Cl/F, Vd/F e t1/2 relativos aos enantiômeros (-)-S e (+)-(R)-VER e aos enantiômeros (S) e (R)-NOR não foram alterados pela exposição em câmara de exposição do tipo nose only ao n-hexano nas concentrações de 88, 176 e 352 mg/m3 e ao tolueno nas concentrações de 94, 188 e 376 mg/m3; teste de Kruskall-Wallis; P<=0,05. No entanto, a exposição ao n-hexano nas concentrações de 176 mg/m3 e 352 mg/m3 e ao tolueno nas concentrações de 94 mg/m3, 188 mg/m3 e 376 mg/m3 resultou em perda da enantiosseletividade observada para o grupo controle. / Verapamil (VER) is a chiral compound which is commercialized as a racemic mixture of the (+)-(R)-VER and (-)-(S)-VER enantiomers. VER is biotransformed into norverapamil (NOR) and other metabolites through CYP-dependent pathways. Toluene and n-hexane are organic solvents that can alter the metabolism of CYP-dependent drugs. The present study investigated the stereoselectivity in the pharmacokinetics of racemic VER administered to rats at a dose of 10 mg kg-1 and of its metabolite NOR. In addition, the influence of n-hexane and toluene on the kinetic disposition of the (+)-(R) and (-)-(S)-VER and (R)- and (S)-NOR enantiomers was analyzed in animals exposed by nose-only inhalation to n-hexane at concentrations of 88, 176 and 352 mg/m3 and to toluene at concentrations of 94, 188 and 376 mg/m3. The VER and NOR enantiomers were separated on a Chiralpak® AD chiral phase column and analyzed by LC-MS/MS (m/z = 441.3->165.5 for the NOR enantiomers and m/z 455.3->165.5 for the VER enantiomers). Pharmacokinetic analysis was performed using a monocompartmental model. The pharmacokinetics of VER was stereoselective in control rats not treated with the solvents, with plasma accumulation of the (-)-(S)-VER eutomer (AUC0-? = 250.8 vs 120.4 ng mL-1 h; P<=0.05, Wilcoxon test). The (S)-NOR metabolite was also found to accumulate in plasma of control animals, with an S/R AUC0-? ratio of 1.5. The pharmacokinetic parameters AUC0-?, Cl/F, Vd/F and t1/2 obtained for the (-)-S-VER, (+)-(R)-VER, (S)-NOR and (R)-NOR enantiomers were not altered by nose-only exposure to n-hexane at concentrations of 88, 176 and 352 mg/m3 or to toluene at concentrations of 94, 188 and 376 mg/m3 (P<=0.05), Kruskal-Wallis test). However, exposure to 176 and 352 mg/m3 n-hexane and to 94, 188 and 376 mg/m3 toluene resulted in the loss of enantioselectivity observed for the control group.

Hidrocarbonetos aromáticos conhecidos como BTEX (benzeno, tolueno, etilbenzeno e xilenos) estão entre os maiores problemas de poluição ambiental. Estes compostos são reconhecidos por sua recalcitrância em ambientes anóxicos, e a remoção destes hidrocarbonetos, de sítios anaeróbios contaminados é dependente da atividade de uma população de microrganismos adaptados capazes de promover a biodegradação destes compostos, nestas condições. Neste sentido, o presente trabalho buscou purificar, caracterizar e utilizar cultura desnitrificante, como inóculo para desenvolvimento de biofilme, em reator anaeróbio de leito fixo preenchido com espumas de poliuretano, além de avaliar o potencial deste biofilme em promover a biodegradação dos compostos de BTEX. Células da cultura apresentaram coloração Gram negativa, com morfologia de cocos (diplococos e cocobacilos). A cultura foi capaz de crescer, sob condições desnitrificantes, utilizando diferentes substratos. A cultura não apresentou capacidade de crescer sob condições sulfetogênicas. Velocidades de crescimento ('mü') de 0,046/h e 0,050/h e tempos de geração (Tg) de 15,1 horas e 13,9 horas foram obtidos para as células crescidas em benzeno e etilbenzeno, respectivamente. A cultura purificada foi utilizada para formar biofilme em RAHLF. Em todas as condições de alimentação as quais os reatores foram submetidos houve remoção da matéria orgânica, nitrato e dos hidrocarbonetos. A menor eficiência de remoção de hidrocarbonetos foi de 89,4%, obtida durante a alimentação dos reatores com benzeno. A matéria orgânica (DQO) foi removida com eficiência média de 87,1%. A eficiência média de remoção de nitrato foi de 94%. O sequenciamento das amostras revelou que o biofilme do RAHLF1 foi formado, principalmente, por espécies de Paracoccus, Pseudomonas e Bacteroides, enquanto que no RAHLF2, alimentado com etilbenzeno, observou-se espécies dos gêneros: Paracoccus, Pseudomonas, Xanthomonas e Variovorax / The monoaromatic hydrocarbons known as BTEX (benzene, toluene, ethylbenzene, and xylene) are among the greatest environmental pollution problems. These compounds are known by their recalcitrance in anoxic environments, and the removal of these toxics from anaerobic contaminated sites depends on the presence of an adapted microbial population capable of to promote the biodegradation of these compounds under such condition. Thus, in the current study a denitrifying culture was purified, characterized and used as inoculum to form a biofilm in a horizontal-flow anaerobic immobilized biomass reactor filled with polyurethane foam, and to assess the potential of this biofilm to promote BTEX compounds biodegradation. Culture cells were Gram negative, with coccus (diplococcus and cocobacilli) morphology. The culture was able to grow, under denitrifying conditions, using different substrates. No growth was seen in sulfate-reducing conditions. Growth velocity('mü') of 0.046/h and 0.050/h, and generation time of 15.1 and 13.9 hours were obtained for cultures isolated in the presence of benzene and ethylbenzene, respectively. The purified culture was used to form a biofilm inside RAHLF. At all feeding conditions the reactors were submitted the organic matter, nitrate and hydrocarbons were removed. The smallest hydrocarbons removal efficiency was 89.4%, obtained during benzene feeding. The organic matter (COD) was removed with mean efficiency of 87.1%. The mean efficiency of nitrate removal was 94.0%. Sequencing of samples showed that the RAHLF1 biofilm was composed specially for Paracoccus, Pseudomonas and Bacteroides species. Biofilm of RAHLF2 reactor, obtained from ethylbenzene feeding, was composed by Paracoccus, Pseudomonas, Xanthomonas and Variovorax species

Sick building syndrome (SBS) is a particular concern in places with inadequate ventilation and frequently attributed to chemical contaminants such as volatile organic compounds (VOCs)released from indoor sources that are frequently encountered in everyday life such as adhesives, carpeting, upholstery, manufactured wood products, copy machines, pesticides, cleaning agents inside buildings, plumbing vents, and painting. Furthermore, it is a major issue for modern human beings who spend most of their time indoors or must stay indoors for self-isolation due to special circumstances such as the coronavirus disease-19 (COVID-19) pandemic that occurred in 2019 and 2020. Main indoor VOCs are trichloroethylene (TCE), benzene, toluene, and para-xylene (p-xylene). In general, these compounds are not present in indoor spaces at acute concentrations, but prolonged exposure to these compounds can have chronic health effects such as allergic sensitization, increased cancer risks, and respiratory diseases. In this study, the adsorption process with various advantages has been applied to remove VOC’s using commercially available hydrophobic adsorbents. The hydrophobic adsorbents can contribute to reducing the possibility of chemical adsorption (chemisorption) of moisture from the air, which can decrease the capacity of adsorbent by clogging the pores. The adsorption of these major VOCs was investigated in this work for three major types of industrial hydrophobic adsorbents: activated carbons, zeolites, and polymer. This study will show the investigation into finding the most promising hydrophobic adsorbent for removal of TCE, benzene, toluene, and p-xylene, which are the main VOCs found indoors. The promising hydrophobic adsorbent has been determined by comparing Henry’s law constants and heat of adsorption values for the different adsorbents, which were estimated by using a concentration pulse chromatographic technique by utilizing a gas chromatograph equipped with a flame ionization detector. For all adsorbents, Henry’s law constants at room temperature of p-xylene were always the highest followed by toluene, benzene, and TCE. For all adsorbates, Henry’s law constants at room temperature of AC BPL and HiSiv 3000 were higher than the other hydrophobic adsorbents. For a developing modern society dealing with a pandemic, this study can contribute to producing the optimized gas masks and indoor filters for the removal of indoor air pollutants, which can help people who suffer from SBS. It can also help society for taking preventative actions towards dealing with SBS.

Benzene is very toxic compound, which has carcinogenic and mutagenic effects. Result of these effects is significant reduction of its use and also low hygienic limits in occupational environment and environment. The aim of this diploma thesis was to map out possible exposure to benzene and checking of clasification correctness of motor gasoline and benzine (cleaners, thinners etc.). Determination of benzene was carried out by gas chromatography with flame ionisation detector (GC/FID) and high performance liquid chromatography with diod array detector (HPLC/DAD). Marginally, the diploma thesis was focused on determination of toluene (in june 2007 became effective ordinance no.284/2006 Sb., which forbid to sell products that contain more than 0,1 % of toluene to small consumers). Toluene was determined by same methods as benzene.

<p>U ovom radu kori&scaron;cen je spektroskopski, teorijski i hemometrijski pristup<br />proucavanju N-HO i N-H&middot;&middot;&middot; vodonicne veze koja se uspostavlja izmedu<br />amidnog protona i etarskog kiseonika tj aromaticnog sistema. U ovom radu<br />odredeni su parametri N-HO i N-H vodonicne veze za &scaron;esnaest Nsupstituisanih<br />amida sa tetrahidrofuranom i toluenom. Vecina ispitivanih amida do<br />sada nije bila izucavana sa stanovi&scaron;ta vodonicne veze. Uspostavljene su korelacije<br />izmedu spektorsopskih i teorijskih parametara. Izvr&scaron;eno je poredenje medu<br />osobinama vodonicno vezanih kompleksa za razlicite amide kao proton donore.<br />Svih 32 ispitivanih vodonicno vezanih kompleksa okarakterisano je<br />hemometrijskim metodama: Klaster analizom i analizom glavne komponente, na<br />osnovu spektroskopskih, teorijskih i Taftovih parametara</p> / <p> In this PhD thesis, N-H&times;&times;&times;O and N-H&middot;&middot;&middot; hydrogen bond beetwen the amide<br /> proton with ether oxygen and aromatic system has been investigated using the<br /> spectroscopic and theoretical approach. The study included sixteen N-substituted<br /> amides (formamides, acetamides, caproamides and benzamides) as well as<br /> tetrahydrofuran and toluene. The possibility of using chemometric methods was<br /> investigated in order to characterise N-H...O and N-H&middot;&middot;&middot; hydrgen bonded<br /> complexes. Hierarchial clustering and Principal Component Analysis (PCA) have<br /> been applied on infrared spectroscopic, PM3 theoretical and Taft parameters of 32 Nsubstituted<br /> amide complexes with tetrahydrofuran and toluene</p>

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