Heterogeneous Photocatalysis Remediation of Wastewater Polluted by Indigoid Dyes

Organic dyes constitute one of the largest groups of wastewater’s pollutants. In general, they are released into the environment by textile industries. Approximately 100,000 dyes are widely used in the textile industry, and a large wastewater of dyestuff is generated annually. Among these, indigoid class is commercial dyes used mostly for cotton cloth dyeing. Indigo carmine (IC) is also one of the oldest dyes and still one of the most used in textile industry and is considered as a very toxic indigoid dye. Most toxic dyes are recalcitrant to biodegradation, causing a decrease in the efficiency of biological wastewater treatment plants. Titanium dioxide is a well-known photocatalyst mostly used in suspensions in photoreactions for wastewater treatment. The use of TiO2 has some advantages such as ease of handling, low cost, low toxicity, high photochemical reactivity, and non-specific oxidative attack ability. In this way, it can promote the degradation of different target organic compounds with little change of operational parameters. The aim of this chapter is to present the different approaches already used in our team for the remediation of waters containing IC mainly through heterogeneous photocatalysis with TiO2. Adsorption over activated carbon (AC) and photocatalytic degradation of IC mediated by titanium dioxide will be revised as well as some studies on the phototoxicity of the photoproducts with aquatic and terrestrial organisms. This chapter makes a comprehensive approach to the different results on the remediation of model effluents containing IC undertaken by this team of researchers

Solar photocatalysis in remediation of indigoides dyeing used in colouring cotton yarn

O objetivo do presente trabalho é avaliar a eficiência da fotodegradação solar do corante índigo carmim mediada pelo dióxido de titânio. O processo de degradação do índigo carmim foi avaliado sob a luz solar na localização S 22°52`37.3``e W 43°15`0.9`` (Rio de Janeiro, Brasil). Volumes de 100 mL de solução aquosa (30 mgL-1) do corante foram irradiados por 5 h na presença de TiO2 (1 gL-1 a 1x10-3 gL-1). As alíquotas (0, 15, 30, 45, 60, 90, 120, 180 e 300 min) do corante foram analisadas por Espectrofotometria UV–Vis, observando λmáx=610nm do corante. A velocidade de degradação aumentou com a concentração de TiO2. Para a luz solar aos 15 min notou-se 99% de degradação para concentração de 1gL-1, enquanto apenas 8% para concentração de 1x10-3 gL-1. A constante de velocidade de degradação diminui para a concentração 1x10-1 gL-1 e aumenta para a concentração 1x10-3 gL-1, sendo que ao final de 5 h ambas degradaram aproximadamente 99% do corante. A fotocatálise mediada pelo TiO2 mostra-se uma alternativa viável e eficaz para o tratamento de efluente contendo resíduos de corantes têxteis. O processo mostra-se mais atraente considerando-se a possibilidade de utilização da radiação solar como meio para diminuir o tempo de reação e o custo energético para o tratamento

Predictors of cut-out after cephalomedullary nail fixation of pertrochanteric fractures: a retrospective study of 813 patients

BACKGROUND: Cut-out is the most common mechanical complication of the osteosynthesis of pertrochanteric fractures. This complication determines a significant increase in morbidity in elderly patient. Cut-out is defined as the varus collapse of the femoral head-neck fragment with the extrusion of the cephalic screw. Surgical treatment of cut-out might lead to further complications, longer rehabilitation, increased social burden and healthcare system costs. The aim of the study is to identify the predictors of cut-out to prevent its occurrence. MATERIALS AND METHODS: Study population included all patients affected by extracapsular fracture of the proximal femur who were admitted and treated with short cephalomedullary nailing at the Cattinara Hospital-ASUITS of Trieste between 2009 and 2014. A retrospective analysis of clinical and radiographic data was carried out and cut-out cases recorded. The data collected on the study population were analyzed to find an eventual correlation with the occurrence of cut-out. The independent variables were age, gender, side of the fracture, ASA class, Evans classification, nailing system, quality of reduction, TAD, CalTAD, and Parker ratio. RESULTS: The study population counted 813 cases, with an F:M ratio of 4:1 and a mean age of 84.7 years. The cut-out was recorded in 18 cases (2.2%). There was no statistically significant association between cut-out and age, sex, side of fracture, ASA class, and nailing system. The Evans classification, the quality of reduction, the TAD, the CalTAD, and the Parker's ratio demonstrated a significant correlation at univariate analysis with cut-out. The results of multivariate analysis confirmed that TAD, Parker AP, and quality of reduction were independently significantly correlated to cut-out. CONCLUSION: The results of the present study demonstrate that good quality of reduction and correct position of the lag screw are likely to decrease the risk of cut-out complication. A nomogram for cut-out prediction is proposed for clinical validation

Advanced oxidation processes for remediation of azo dyes used in the textile industry

O objectivo deste trabalho visa avaliar a degradação fotocatalitica dos corantes azo Remazol Amarelo Ouro, Azul e Carbon RGB. Para tal foram avaliados os seguintes parâmetros: concentração de TiO2, concentração do corante, efeito do H2O2, efeito do pH e da reciclagem de TiO2. TiO2 Degussa P25 foi testado em concentrações a partir de 0gL-1 a 1 gL-1. A concentração do corante foi de 30 mgL-1 a 120 mgL-1 e a concentração do peróxido de hidrogénio foi de 0.3x10-3 a 6x10-2 mol L-1. A variação do pH foi de 2 a 11 e de reciclagem de TiO2 foi feita com 5 ciclos. As amostras foram tratadas durante duas horas com irradiação artificial (lâmpada de vapor mercúrio, 125W) e as amostras foram recolhidas aos 0, 15, 30, 45, 60, 90 e 120 minutos. A fotodegradação das amostras foi seguida por espectroscopia UV-Vis. A eficiência da degradação fotocatalítica aumentou com o aumento da quantidade de TiO2. O efeito do H2O2 foi benéfico para a degradação dos 3 corantes. Os resultados indicam que a degradação fotocatalítica depende da concentração de corante, da quantidade de fotocatalisador utilizado, irradiação UV vs tempo, do pH da solução e da concentração de peróxido de hidrogénio adicionado

Human adenovirus in municipal solid waste leachate and quantitative risk assessment of gastrointestinal illness to waste collectors

Leachate is a variable effluent from waste management systems generated during waste collection and on landfills. Twenty-two leachate samples from waste collection trucks and a landfill were collected from March to December 2019 in the municipality of Rio de Janeiro (Brazil) and were analyzed for Human Adenovirus (HAdV), bacterial indicators and physico-chemical parameters. For viral analysis, samples were concentrated by ultra centrifugation and processed for molecular analysis using QIAamp Fast DNA Stool mini kit (R) for DNA extraction followed by nested-PCR and qPCR/PMA-qPCR TaqMan (R) system. HAdV was detected by nested-PCR in 100% (9/ 9) and 83.33% (12/13) of the truck and landfill leachate samples, respectively. Viral concentrations ranged from 8.31 x 10(1) to 6.68 x 107 genomic copies per 100 ml by qPCR and PMA-qPCR. HAdV species A, B, C, and F were characterized using nucleotide sequencing. HAdV were isolated in A549 culture cells in 100% (9/9) and 46.2% (6/13) from truck and landfill leachate samples, respectively. Regardless of the detection methods, HAdV concentration was predicted by the quantity of total suspended solids. A quantitative microbial risk assessment was performed to measure the probability of gastrointestinal (GI) illness attributable to inadvertent oral ingestion of truck leachate, revealing the higher probability of disease for the direct splashing into the oral cavity (58%) than for the gloved hand-to-mouth (33%). In a scenario where waste collectors do not wear gloves as protective personal equipment, the risk increases to 67%. This is the first study revealing infectious HAdV in solid waste leachate and indicates a potential health risk for waste collectors

Contamination and oxidative stress biomarkers in estuarine fish following a mine tailing disaster

Background The Rio Doce estuary, in Brazil, was impacted by the deposition of iron mine tailings, caused by the collapse of a dam in 2015. Based on published baseline datasets, the estuary has been experiencing chronic trace metal contamination effects since 2017, with potential bioaccumulation in fishes and human health risks. As metal and metalloid concentrations in aquatic ecosystems pose severe threats to the aquatic biota, we hypothesized that the trace metals in estuarine sediments nearly two years after the disaster would lead to bioaccumulation in demersal fishes and result in the biosynthesis of metal-responsive proteins. Methods We measured As, Cd, Cr, Cu, Fe, Mn, Pb, Se and Zn concentrations in sediment samples in August 2017 and compared to published baseline levels. Also, trace metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Se and Zn) and protein (metallothionein and reduced glutathione) concentrations were quantified in the liver and muscle tissues of five fish species (Cathorops spixii, Genidens genidens, Eugerres brasilianus, Diapterus rhombeus and Mugil sp.) from the estuary, commonly used as food sources by local populations. Results Our results revealed high trace metal concentrations in estuarine sediments, when compared to published baseline values for the same estuary. The demersal fish species C. spixii and G. genidens had the highest concentrations of As, Cr, Mn, Hg, and Se in both, hepatic and muscle, tissues. Trace metal bioaccumulation in fish was correlated with the biosynthesis of metallothionein and reduced glutathione in both, liver and muscle, tissues, suggesting active physiological responses to contamination sources. The trace metal concentrations determined in fish tissues were also present in the estuarine sediments at the time of this study. Some elements had concentrations above the maximum permissible limits for human consumption in fish muscles (e.g., As, Cr, Mn, Se and Zn), suggesting potential human health risks that require further studies. Our study supports the high biogeochemical mobility of toxic elements between sediments and the bottom-dwelling biota in estuarine ecosystems

Effect of titanium dioxide in the photocatalytic decomposition of persistent chemicals in the environment: textiles and dyes endocrine interfering

Submitted by Repositório Arca ([email protected]) on 2019-09-10T13:02:59Z No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) enrico_mendes.pdf: 2530016 bytes, checksum: c56f4b0c79906baf52c2683f3d2e6537 (MD5)Approved for entry into archive by Erasmo Martins ([email protected]) on 2019-10-02T13:40:14Z (GMT) No. of bitstreams: 2 enrico_mendes.pdf: 2530016 bytes, checksum: c56f4b0c79906baf52c2683f3d2e6537 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5)Made available in DSpace on 2019-10-02T13:40:14Z (GMT). No. of bitstreams: 2 enrico_mendes.pdf: 2530016 bytes, checksum: c56f4b0c79906baf52c2683f3d2e6537 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2014Fundação Oswaldo Cruz. Escola Nacional de Saúde Pública Sergio Arouca. Rio de Janeiro, RJ, Brasil.O objetivo do presente trabalho foi estudar a degradação fotocatalítica de três corantes e um interferente endócrino mediado pelo dióxido de titânio (TiO2). Foi estudada a degradação fotocatalítica de dois azo corantes comerciais, respectivamente o C.I Reactive Black 5 e o C.I Reactive Red 239. Para esse estudo foi utilizado o TiO2 P25 Evonik como catalisador e os experimentos foram realizados em solução aquosa com reator artificial equipado com lâmpada de vapor de mercúrio 125W. Nesse estudo, foram avaliados os seguintes parâmetros: concentração de TiO2, tempo de irradiação, pH, concentração inicial de corante, presença de diferentes concentrações de peróxido de hidrogênio e degradação em sistema bi-compartimental para os dois azo corantes. O outro corante estudado foi o Índigo Carmine (IC). Primeiramente foi investigada a descoloração do corante em efluente modelo usando processo físico e químico para sua remoção. Os experimentos de descoloração do efluente contendo o corante IC foram realizados usando carvão ativado no escuro e com irradiação. Além disso, o efeito do carvão ativado/TiO2/UV foi avaliado pelo mesmo sistema. Os parâmetros da degradação do IC foram realizados, seguindo: concentração de TiO2, pH, concentração inicial de corante, presença de ânions inorgânicos, temperatura, concentração de peróxido de hidrogênio. A eficiência de três diferentes reatores (Reator 1 – reator do tipo batch com lâmpada vapor de mercúrio 125W; Reator 2 – reator do tipo batch equipado com 4 lâmpadas daylight 20W; Reator 3 – reator tubular de fluxo contínuo equipado com uma lâmpada daylight 20W) e reator batch com luz solar foram avaliados para degradação do IC. Além disso, otimizados experimentos foram realizados em planta piloto com compound parabolic collector reatores (CPC) na Plataforma Solar de Almería, Espanha, com TiO2 em suspensão e suportado. O IC foi estudado em diferentes tipos de águas, sendo elas: água destilada, água sintética moderadamente dura, água sintética e real de estação de tratamento de água residuária (ETAR). Testes ecotoxicológicos para o IC foram realizados em dois diferentes níveis tróficos de cadeia alimentar (Daphnia similis e Pseudokirchneriella subcapitata) e testes com minhocas Eisenia andrei. A degradação fotocatalítica do Bisfenol A (BPA) em diferentes tipos de águas na presença de TiO2 foi feita sob diferentes condições. O TiO2 em suspensão foi utilizado para comparar a eficiência da degradação do BPA (20 mgL-1 ) em batch e CPC reatores. O TiO2 foi suportado em esferas de vidro pelo método sol-gel e usado em reatores solares CPC em escala piloto para degradação do BPA (100 µgL-1 ). A influência das espécies reativas (OH• , O2 •- , h + ) foi avaliada. Testes ecotoxicológicos com minhocas Eisenia andrei também foram realizados para o BPA e seus produtos de degradação.The aim this study was evaluated the photocatalytic degradation mediated titanium dioxide (TiO2) for three dyes and one endocrine disruptor. The photocatalytic degradation of two commercial textile azo dyes, respectively C.I Reactive Black 5 and C.I Reactive Red 239 has been studied. TiO2 P25 Evonik was used as catalyst and photodegradation was carried out in aqueous solution under artificial irradiation with a 125W mercury vapor lamp. The effects of the amount of TiO2 used, UV-light irradiation time, pH of the solution under treatment, initial concentration of the azo dye and addition of different concentrations of hydrogen peroxide were investigated. The effect of the simultaneous photodegradation of the two azo dyes was also investigated. The other dye studied was Indigo Carmine (IC). First was investigated the decolorization of a model water effluent containing indigo carmine dye under physical and chemical different treatments. Experiments on decolorization of the effluent containing indigo dye were performed using activated carbon in the dark and under irradiation. Furthermore the effect of activated carbon/TiO2/UV was tested for the same system. The effects of parameters in the IC degradation were evaluated under artificial irradiation with a 125 W mercury vapor lamp. The effects of the amount of TiO2, pH of the solution, initial concentration of the dye, presence of inorganic anions, temperature and addition of different concentrations of hydrogen peroxide were investigated. The efficiency of three different artificial photoreactors (Reactor 1 – batch magnetically stirred reactor with 125 watts mercury vapor lamp; Reactor 2 - batch magnetically stirred reactor with 4 lamps daylight 20 watts; Reactor 3 - glass tubular continuous-flow reactor, illuminated inside by one daylight 20W lamp) were evaluated. Also, the same parameters were evaluated for batch solar experiments. Furthemore, the optimized experiments was performed in a solar compound parabolic collector (CPC) pilot plant in Plataforma Solar de Almería, Espanha, under suspended and supported TiO2. IC was spiked in several types of water such as distilled water, synthetic moderately hard freshwater, synthetic and real secondary municipal wastewater treatment plant (MWWTP). The ecotoxicological effects of IC were evaluated for two different food chain levels (Daphnia similis and Pseudokirchneriella subcapitata) and Eisenia andrei earthworms. Photocatalytic degradation of Bisphenol A (BPA) in waters and wastewaters in the presence of titanium dioxide (TiO2) was performed under different conditions. Suspensions of the TiO2 were used to compare the degradation efficiency of BPA (20 mgL-1 ) in batch and CPC reactors. A TiO2 catalyst supported on glass spheres beads was prepared (sol-gel method) and used in a CPC solar pilot plant for the photodegradation of BPA (100 µgL-1 ). The influence of OH• , O2 •- , h + on the BPA degradation were evaluated. Some toxicological effects of BPA and its photoproducts on Eisenia andrei earthworms were evaluated

Per un'archeologia di montagna: alcune riflessioni

Si tratta di una riflessioni sull'archeologia di montagna, analizzando lo stato della questione da diversi punti di vst