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1.
Environ Res ; 211: 112971, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35276188

RESUMEN

The contamination of water by pharmaceutical pollutants is a major issue these days due to excessive use of these ingredients in modern life. This study evaluated the adsorption and effectiveness of a low-cost composite prepared from heavy sugarcane ash (HSA) fused with polyethylene terephthalate (PET) and functionalized with iron (Fe3+) in a dynamic system through a fixed-bed column. The solution of synthetic drugs was prepared and placed in a reservoir, using a peristaltic pump the solution is run onto the fixed bed column at a flow rate of 2 mL min-1. Saturation time and adsorption capacity were evaluated by centrifugation and extraction after a regular interval of 2 h from the adsorption column. The samples were analyzed using high-performance liquid chromatography (HPLC) and the data was modeled for quantification. For DIC removal, an adsorption capacity of 324.34 µg. g-1 and a saturation time of 22 h were observed, while the adsorption capacity of NAP was 956.49 µg. g-1, with a saturation time of 8 h. Thus, the PETSCA/Fe3+ adsorbent proved to be quite efficient for removing the pharmaceutical pollutants, with a longer period of operation for DIC removal. These findings suggested that a highly efficient bed column made from a less expensive waste material and could be used to remove hazardous pharmaceutical contaminants.


Asunto(s)
Saccharum , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Diclofenaco , Naproxeno/análisis , Preparaciones Farmacéuticas , Tereftalatos Polietilenos , Agua/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
2.
Chemosphere ; 289: 133222, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34902391

RESUMEN

Every year, a considerable volume of medications is consumed. Because these medications are not entirely eliminated in the sewage treatment plants and impact the surface waterways, the environmental pollution problem arises. This study objective was to evaluate the possibility of using an absorbent material made with of polyethylene terephthalate and sugarcane bagasse ash functionalized with iron oxide (PETSCA/Fe3+) in the removal of naproxen from water. The feasibility of having viable features in becoming an efficient adsorbent was first determined. The batch test was performed, allowing the dose effect, adsorption kinetics, and isotherm models to be evaluated. The determination of naproxen (NAP) concentration in water was analyzed on a high-performance liquid chromatograph and Langmuir method best represented the adsorption isotherm model. PETSCA/Fe3+ adsorbent material demonstrated potential in the naproxen removal at a low cost. The batching process was satisfactory, with 0.30 g of composite being the optimum fit for the system. The adsorption kinetics was determined and described by the pseudo second order model, with an average correlation coefficient (R2) of 0.974. The adsorption system model was best represented by the Langmuir isotherm curve. Moreover, adsorption in the presence of H2O2 had a positive impact on the process, removing 81.9% of NAP, whereas the process without H2O2 did not remove more than 62.0% of NAP. Therefore, because of its good qualities for NAP removal, PETSCA/Fe3+ is recommended as adsorbent material, primarily in small-volume water filtration systems.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Compuestos Férricos , Peróxido de Hidrógeno , Concentración de Iones de Hidrógeno , Cinética , Naproxeno , Agua , Contaminantes Químicos del Agua/análisis
3.
Eng. sanit. ambient ; 26(2): 381-388, Mar.-Apr. 2021. tab, graf
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1249766

RESUMEN

RESUMO Nos centros populacionais, os ambientes aquáticos estão em constante degradação em consequência das atividades desenvolvidas nas bacias de drenagem, sendo o despejo de esgoto doméstico uma das maiores fontes de poluição. Monitoramentos ambientais de qualidade da água refletem os poluentes gerados nas áreas de influência e dão indícios das prováveis origens. Todavia, são as substâncias de uso exclusivamente antrópico que podem comprovar a existência do lançamento de tais cargas poluidoras. Nesse contexto, o presente trabalho teve como objetivo avaliar a eficiência da cafeína como indicador de poluição por esgoto doméstico. O método analítico utilizado para a sua identificação foi a cromatografia líquida de alta eficiência. Com o intuito de relacionar os resultados obtidos para a cafeína com a diluição e as fontes difusas de poluição, foram aferidos, ainda, dados de precipitação, oxigênio dissolvido e demanda bioquímica de oxigênio. A cafeína foi encontrada em todas as amostras analisadas, com concentrações variando de 0,01 a 7,80 mg.L−1. Os maiores valores foram observados no período chuvoso, relacionados ao transbordamento e ao vazamento de esgoto doméstico. Este estudo inferiu a utilização da cafeína como eficiente indicador de poluição por esgoto doméstico.


ABSTRACT In population centers, aquatic environments are in constant degradation due to the activities carried out in watersheds, with the release of domestic sewage being one of the biggest sources of pollution. Environmental monitoring of water quality reflects the inputs generated in the areas of influence and gives evidence of likely origins. However, it is the substances for exclusively anthropic use that can prove the existence of the release of such polluting loads. In this context, the present study aimed to evaluate the efficiency of caffeine as an indicator of pollution by domestic sewage. The analytical method used for its identification was high-performance liquid chromatography (HPLC). In order to relate the results obtained for caffeine with the dilution and nonpoint sources pollution, data on precipitation, dissolved oxygen, and biochemical oxygen demand were also measured. Caffeine was found in all samples analyzed, with concentrations ranging from 0.01 to 7.80 mg.L−1. The highest values were observed in the rainy season, related to the overflow and leakage of domestic sewage. This study infered the use of caffeine as an efficient indicator of pollution by domestic sewage.

4.
Eng. sanit. ambient ; 26(2): 263-272, Mar.-Apr. 2021. tab, graf
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1249769

RESUMEN

RESUMO A atrazina é um herbicida sintético comumente utilizado no controle de ervas gramíneas daninhas e folhagens em lavouras, e é um dos principais contaminantes dos solos e dos ecossistemas aquáticos. Muitos métodos têm sido sugeridos para remover herbicidas da água potável. Contudo, esses métodos são custosos, muitos têm problemas de desempenho, produzem diversos subprodutos intermediários tóxicos, prejudiciais e perigosos. Entretanto, a atrazina é susceptível à degradação por microrganismos presentes na água, no sedimento e no esgoto. Considerando esses aspectos, o objetivo principal do estudo foi investigar a biodegradação e a filtração por meio de filtros de carvão com atividade biológica (CAB) para remoção da atrazina, e sua identificação filogenética associada a esses microrganismos. Os resultados demonstraram que a atrazina foi degradada por microrganismos presentes no biofilme, com remoção superior a 89% nos filtros CAB. Os microrganismos encontrados integram-se ao grupo das bactérias, composto dos gêneros Acinetobacter,Bacillus, Exiguobacterium e Pseudomonas. Este estudo nos permite inferir sobre a capacidade de biodegradação da atrazina por bactérias presentes nos filtros CAB, a capacidade de remover herbicidas por meio desse sistema de filtros e a possível utilização dessa tecnologia como alternativa para o controle e a remoção dessa substância no tratamento de água.


ABSTRACT Atrazine is a synthetic herbicide commonly used to control weeds and foliage in crops, and is a major contaminants of soil and water ecosystems. Many methods have been suggested to remove herbicides from drinking water. However, these methods are very costly, many have performance problems, produce a lot of toxic intermediates which are very harmful and dangerous. However, atrazine is susceptible to degradation by microorganism present in water, sediment, and sewage effluents. Considering these aspects, the main objective of the study was to investigate the biodegradation and filtration for using biological activated carbon (BAC) filters to remove atrazine, and their phylogenetic identification associated with these microorganisms. The results showed that atrazine was biodegraded by microorganism present in the biofilm, with removal over 80% in BAC filters. The microorganisms found integrate to the group of bacteria, composed by the genera Acinetobacter, Bacillus, Exiguobacterium, and Pseudomonas. This study allows us to infer the ability to biodegrade atrazine by bacteria present in BAC filters and capacity to remove herbicides by BAC filters, and the possible use of this technology as an alternative for the control and removal of this substance in water treatment.

5.
Environ Technol ; 42(13): 2095-2111, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-31714186

RESUMEN

This work objective was to evaluate batch adsorption processes using polyethylene terephthalate composite (PTC) material, sugarcane bagasse ash (SBA) functionalized with iron oxide (Fe3+) (PTCSBA/ Fe3+) in the adsorption of 1000 µg  L-1 of diclofenac sodium (DIC) in synthetic solution, simulating water supply. The batch test was started by determining the adsorbent mass (0.1, 0.2, 0.3, 0.4 and 0.5 g) to remove 1000 µg L-1 of DIC, followed by the adsorption kinetics and adsorption isotherm assays, evaluating the reaction rate and adsorption capacity, respectively. The PTCSBA/ Fe3+ mass that had the best efficiency in the DIC removal was 0.3 g, the pseudo second-order kinetic model (PSO) was the one that best fit the study having a determination coefficient (R2) equals to 0.97. The PTCSBA/ Fe3+ has good characteristics for DIC adsorption, achieving a 93% removal rate of sodium diclofenac. The composite is a low-cost adsorbent, 0.08 cents per kilogram of material, becoming a material with satisfactory characteristics for the removal of DIC. Therefore, it is recommended to use PTCSBA/ Fe3+ as adsorbent material in small water filter systems in order to remove DIC due to the low cost of the composite.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Diclofenaco , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua
6.
Eng. sanit. ambient ; 22(3): 429-435, mai.-jun. 2017. tab, graf
Artículo en Portugués | LILACS | ID: biblio-840420

RESUMEN

RESUMO Os objetivos deste trabalho foram avaliar a presença e a concentração dos anti-inflamatórios diclofenaco e naproxeno em um córrego urbano localizado no município de Três de Lagoas, Mato Grosso do Sul, que recebe efluente de uma estação de tratamento de esgoto; e verificar a influência da temperatura da água na ocorrência dos fármacos em águas superficiais. Foi realizado monitoramento dos anti-inflamatórios e dos parâmetros temperatura, pH e oxigênio dissolvido na água durante 12 meses consecutivos (outubro de 2008 a setembro de 2009). Foram coletadas amostras de água mensalmente em seis pontos, representando diferentes seções do córrego. As amostras foram submetidas ao processo de extração em fase sólida e analisadas por cromatografia líquida de alta eficiência. Para verificar a influência da temperatura da água na ocorrência dos anti-inflamatórios diclofenaco e naproxeno nos ambientes aquáticos, utilizou-se um modelo de regressão logística do Statistical Analysis System versão 9.0. Os anti-inflamatórios diclofenaco e naproxeno foram detectados nos diferentes pontos monitorados no Córrego da Onça. Os demais parâmetros avaliados neste estudo foram comparados com os padrões de qualidade de água estabelecidos pela Resolução CONAMA nº 357/2005. A maior concentração do diclofenaco foi detectada no ponto localizado à jusante da estação de tratamento de esgoto do município, enquanto a maior concentração de naproxeno foi registrada na foz do córrego. A temperatura da água influencia de forma inversamente proporcional a ocorrência dos dois anti-inflamatórios no córrego, ou seja, quanto maior a temperatura do corpo hídrico, menor a probabilidade de detecção dos fármacos diclofenaco e naproxeno.


ABSTRACT The aims of this study were to evaluate the presence and concentration of the anti-inflammatory drugs diclofenac and naproxen in an urban stream located in Três Lagoas, Mato Grosso do Sul, Brazil, that receives effluent from a wastewater treatment plant; and to evaluate the influence of water temperature in the occurrence of these drugs into surface waters. Monitoring of both anti-inflammatory and the parameters temperature, pH and dissolved oxygen was held in this water body during 12 consecutive months (October 2008 to September 2009). Water samples were collected monthly at six points representing different sections of the stream. The samples were subjected to solid phase extraction procedure and analyzed by high performance liquid chromatography. To check the influence of water temperature on the occurrence of the anti-inflammatory drugs diclofenac and naproxen in aquatic environments, it was used a logistic model of regression, the Statistical Analysis System version 9.0. The anti-inflammatory drugs diclofenac and naproxen were detected at different points in the Stream of Onça. The other parameters evaluated in this study were compared with the water quality standards established by the CONAMA Resolution 357/2005. The highest concentration of diclofenac was detected in the point located downstream of the wastewater treatment plant of the city, while the largest concentration of naproxen was recorded at the mouth of the stream. The water temperature influence, in an inversely proportional way, the occurrence of both anti-inflammatory in the stream, the higher the temperature the lower the water body probability of detection of drug diclofenac and naproxen.

7.
Eng. sanit. ambient ; 18(3): 205-214, July-Sept/2013. tab, graf
Artículo en Portugués | LILACS | ID: lil-690023

RESUMEN

A persistência das microcistinas (MCs) em ambientes aquáticos e sua difícil remoção no tratamento convencional de água representam um desafio às companhias de saneamento. Contudo, as MCs são susceptíveis à degradação por bactérias presentes na água, sedimentos e efluentes de esgotos. Neste estudo, avaliou-se a biodegradação de MCs por microrganismos presentes em filtros de carvão com atividade biológica (CAB) e sua identificação filogenética pelo sequenciamento do gene 16S RNA. Foi utilizada uma água de estudo contendo MCs com diferentes composições, acrescida de efluente de filtros CAB. Os resultados demonstraram que as MCs foram biodegradadas por microrganismos presentes no biofilme. Este estudo infere sobre a capacidade de biodegradação de MCs por bactérias presentes em filtros CAB e o possível uso destes microorganismos como alternativa de remoção de MCs no tratamento de água potável.


The persistence of MCs in aquatic environments and their difficult removal in the conventional water treatment is a challenge to companies of sanitation. However, the MCs are susceptible to degradation by bacteria present in water, sediment and sewage effluents. In this study, we investigated the biodegradation of MCs by microorganism present in carbon filters with biological activity (BAC) and their phylogenetic identification by sequencing gene 16S RNA. A study of water containing MCs was used, with different compositions, plus a filters BAC effluent. The results showed that of MCs were biodegraded by microorganism present in the biofilm. This study provides the ability to complete biodegradation of MCs by bacteria present in BAC filters and the possible use of these microorganisms as alternative of the removal of MCs in the treatment of drinking water.

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