Repositório RCAAP

Effect of the riparian vegetation removal on the trophic network of Neotropical stream fish assemblage

Abstract The study of the diet of fish is an important tool to assess different levels of environmental degradation, since the availability of food in the environment is a key factor for the fish occurrence. The removal of riparian vegetation usually degrades environmental quality, as this vegetation has an important role in providing energy to the ecosystem. This study investigates the effects of the removal of riparian vegetation on the fish assemblage trophic network. The study was carried out in two stretches of a southeastern Brazilian stream, one in a forest fragment and another in a pasture, during the wet and dry seasons of 2014. We analyzed the items consumed by each fish species using the frequency of occurrence and area of each item, which were combined to calculate the alimentary index, which was used to determine the food niche overlap of the fish and the specialization index of the trophic network. Aquatic Hexapoda, vegetal debris and organic matter dominated the trophic network of the two stretches. We detected higher values of food niche overlap in the forested stretch and more complex trophic networks in the pasture stretch. We found few seasonal variations in the items consumed and calculated indices in both stretches studied. The presence of grass on the banks in the pasture stretch and the importation of food resources from the upstream area may have provided a higher diversity of resources and consequently showed a more complex trophic network when compared to the forested stretch.

Ano

2018

Creators

Manoel,Pedro Sartori Uieda,Virginia Sanches

Cálculo de precipitação média utilizando método de Thiessen e as linhas de cumeada

Resumo O presente estudo propõe um método para calcular as áreas de influência baseado no Método de Thiessen e considerando as linhas de cumeada do relevo. O estudo foi estabelecido para a bacia do Alto Sapucaí, a montante da cidade de Itajubá-MG, e foram usados os dados das estações de monitoramento de enchentes da Universidade Federal de Itajubá. Também foram utilizadas imagens da Shuttle Radar Topography Mission (SRTM). Com esses dados, foram traçadas áreas de influência das estações pluviométricas, por meio da junção do Método de Thiessen e das linhas de cumeadas mais próximas dessas medições de pluviosidade. Acredita-se que com isso os resultados das áreas de influência de uma estação climatológica sejam mais precisos que outros métodos recomendados pela bibliografia especializada.

Ano

2018

Creators

Marciano,Alexandre Germano Barbosa,Alexandre Augusto Silva,Ana Paula Moni

Determinação e interpolação dos coeficientes das equações de chuvas intensas para cidade do Rio de Janeiro

Resumo Este estudo teve como objetivo estabelecer a relação entre intensidade, duração e frequência das precipitações na cidade do Rio de Janeiro, e avaliar os métodos de interpolação dos coeficientes das equações de chuvas intensas, para determinação das equações em qualquer localidade do município. Os dados de chuvas foram obtidos por meio da rede de estações pluviométricas automáticas do Sistema Alerta Rio da Fundação Instituto de Geotécnica do município do Rio de Janeiro. Foram analisadas as precipitações intensas com base em séries históricas de observações obtidas a cada 15 minutos, no período de 1997 a 2014. Determinaram-se as maiores precipitações anuais para as durações de 15, 30, 60, 120, 240, 360, 720, e 1440 minutos. Os dados foram ajustados pelo método de distribuição de Gumbel e a aderência dos dados à distribuição foi avaliada pelo teste de Kolmogorov-Smirnov a 5% de significância. A espacialização dos coeficientes foi avaliada pelos métodos de interpolação do inverso da quinta potência da distância e Krigagem ordinária. As precipitações intensas apresentaram grande variabilidade espacial. Observou-se boa relação entre os valores de precipitação intensa calculados com o uso da equação ajustada com os valores oriundos das equações determinadas em outros trabalhos sobre chuvas intensas para a cidade do Rio de Janeiro. Os valores do coeficiente de determinação R2 e erro padrão de estimativa permitiram concluir que as equações propostas podem ser utilizadas em projetos de obras hidráulicas. O método de interpolação inverso da quinta potência da distância apresentou melhor desempenho para a espacialização dos coeficientes das equações de chuvas intensas, e menores valores de erro médio percentual em 25 das 32 estações analisadas.

Ano

2018

Creators

Braga,Raphael Nunes de Siqueira Hora,Mônica de Aquino Galeano Massera da Lyra,Gustavo Bastos Nascentes,Alexandre Lioi

Climatic zoning for eucalyptus cultivation through strategic decision analysis

Abstract The rapid expansion of eucalyptus cultivation necessitates studies that can identify areas amenable to the planting and development of its different varieties. This study therefore aimed to verify the suitability of two varieties of eucalyptus in the state of Espírito Santo, using Geographic Information Systems supported by strategic decision analysis. Mean precipitation, mean temperature, hydric deficit and land slope data were used as decision factors. These factors were submitted to fuzzy standardization, aggregated and compensated by the Weighted Linear Combination (WLC) process, resulting in the final aptitude mapping. For the reconciliation of conflict areas between the varieties, the Multi-objective Land Allocation (MOLA) module was used to maximize the suitability of the land for the objective. The WLC analysis allowed us to identify the suitability of the areas and with the use of the MOLA module it was possible to resolve the conflict of suitability between the two eucalyptus varieties. Most of the state of Espírito Santo is highly suitable for the the development of varieties. The northwestern region and part of the northern region presented less suitability for both analyzed eucalyptus varieties. Considering the 10,000 km2 most adaptable area for eucalyptus cultivation in the state of Espírito Santo, it was verified that the most suitable areas for planting the two eucalyptus varieties are located in the mountainous regions, part of the southern region and near the northeastern coast.

Ano

2018

Creators

Fraga,Micael de Souza Uliana,Eduardo Morgan Silva,Demetrius David da Campos,Flávio Bastos Calijuri,Maria Lúcia Santos,Diego Magalhães de Souza

Sanitary quality of the rivers in the Communities of Manguinhos´ Territory, Rio de Janeiro, RJ

Abstract Sanitation actions are rare in the communities of Manguinhos, so evaluation of the sanitary conditions of the river waters and the peridomestic soils of the communities allows the diagnosis of the risk of contamination. This study evaluated coliform levels (total coliforms and Escherichia coli) by the filter membrane method, and parasitological (by adapted Lutz and Baermann-Moraes methods) in the waters and soils of the Faria-Timbó, Jacaré and Canal do Cunha Rivers that pass through the communities of the Territory of Manguinhos, RJ, according to the standards established in Brazilian legislation. In all points of the rivers, the water was unfit, with an average level of Escherichia coli 3,800 times higher than that standardized in CONAMA Resolution No. 274/2000. Larvae, helminths eggs and protozoan oocysts were observed. Soil samples were also unfit, with mean total coliform level 77,000 times higher than that considered acceptable by SMAC Resolution 468/2010. The Escherichia coli average level was 53,000 times higher than that permitted by the legislation. However, helminths eggs were found in only one soil sample. It was concluded that the lack of sanitation in this locality results in the high coliform and parasitological levels of the river waters and in the peridomestic soils, and that immediate modifications are needed to the Brazilian environmental paradigm, which uses its water bodies as sewage disposal ditches.

Ano

2018

Creators

Handam,Natasha Berendonk Santos,José Augusto Albuquerque dos Moraes Neto,Antonio Henrique Almeida de Duarte,Antonio Nascimento Alves,Elizabeth Brito da Silva Salles,Maria José Sotero-Martins,Adriana

Urban influence on the water quality of the Uberaba River basin: an ecotoxicological assessment

Abstract Ecotoxicological tests applied to Tradescantia pallida, Allium cepa and Lactuca sativa were used to assess the quality of the Uberaba River basin under urban area influence. Water samples were collected at eight different points during the dry season. The samples were assessed using the following toxicity indicators: micronuclei percentage in T. pallida pollen grains (TRAD-MN), seed germination, root growth, mitotic index (MI) and micronuclei in A. cepa root-cells, and seed germination and root growth in L. sativa. Water physicochemical parameters such as temperature, dissolved oxygen (DO), pH and electric conductivity were assessed in situ. The three plant species were efficient bio-indicators, since they presented good cost-benefit and fast and easily interpreted results, thus completing the physicochemical parameters. There was strong correlation between seed germination and root growth among the ecotoxicological parameters assessed in L. sativa and A. cepa. The micronuclei percentage in T. pallida and the MI in A. cepa presented strong correlation with water electric conductivity and moderate and negative correlation with DO. Water electric conductivity ranged from 75 to 438 µS.cm-1; and the DO concentrations ranged from 0.5 to 6.9 mg.L-1. The importance of pollution control measures in the Uberaba River basin stands out. From the supply-water capture point, the basin is strongly affected by pollution, mainly in the tributaries that cross the city. It presents a short, or almost absent, riparian forest line, residues on the river banks, and it is impacted by discharges of untreated sewage, among other anthropic actions.

Ano

2018

Creators

Curado,Ana Luisa Oliveira,Camila Cunha de Costa,William Raimundo Anhê,Ana Carolina Borella Marfil Senhuk,Ana Paula Milla dos Santos

Short-term dermal exposure to tannery effluent does not cause behavioral changes in male Swiss mice

Abstract Tannery is a highly polluting activity due to the waste generated by bovine skin processing. Although there are several studies highlighting the health issues faced by workers exposed to tannery effluent, there are no records of experiments testing the neurobehavioral effects resulting from direct contact with this pollutant. Thus, the aim of the current study is to assess the possible neurobehavioral effects of dermal exposure to tannery effluent on male Swiss mice. Animals were divided in three groups, which were subjected to the same experimental time period and conditions: effluent group - animals in direct contact with tannery effluent (for 20 days); control group - animals in contact with pure water; and dry-control group - animals not exposed to water or to tannery effluent. Neurobehavioral tests started on the 17th experimental day. Results of the elevated plus-maze test (anxiety prediction) showed no anxiogenic or anxiolytic effects, memory deficit or depressive symptoms on animals exposed to tannery effluent. Thus, the current results do not support the hypothesis that male Swiss mice dermal exposure to tannery effluents for the same time period and experimental conditions leads to neurobehavioral changes. Therefore, the herein adopted exposure protocol was not good to study the effects of dermal exposure to tannery effluent on the chosen experimental model.

Ano

2018

Creators

Mendes,Bruna de Oliveira Guimarães,Abraão Tiago Batista Souza,Joyce Moreira de Ferreira,Raíssa de Oliveira Silva,Wellington Alves Mizael da Rodrigues,Aline Sueli de Lima Malafaia,Guilherme

Impact of spineless cactus cultivation (O. Ficus-indica) on the thermal characteristics of soil

Abstract Temperature is a fundamentally important factor for understanding the physical, chemical, and biological processes that occur in soil. However, there are few studies in the Brazilian semiarid zone that seek to understand how soil degradation affects its thermal characteristics. The objective of this study was to evaluate the influence of cultivation techniques on the thermal characterization of soil, using the model proposed by Johansen. The study was conducted in the Agreste region of the state of Pernambuco, Brazil on two plots of land, one with native vegetation (Caatinga) and the other with spineless cactus (O. ficus - indica). It was observed that the procedures used to prepare the soil for cultivation of spineless cactus caused a reduction in the capacity to transmit the surface temperature to the interior of the soil. Changes in the physical properties of the soil required for cultivation resulted in a reduction in the average value of the volumetric heat capacity of about 22%; an increase of approximately 5% in the average volumetric heat capacity and a 26% increase in the thermal diffusivity of the soil, as well as a reduction of approximately 50% in the heat flux from the surface of the soil.

Trends in daily precipitation in highlands region of Santa Catarina, southern Brazil

Abstract This study evaluates the occurrence of trends in time series of precipitation in the highlands region of Santa Catarina, Southern Brazil. Daily precipitation data of three weather stations at Lages, São Joaquim and Campos Novos were used to evaluate rainfall trends. The trends were analyzed through the Seasonal Mann Kendall test, to include occurrence of maximum annual 1-day precipitation (RX1), maximum annual consecutive 2-day precipitation (RX2) and maximum annual consecutive 3-day precipitation (RX3) and evaluation of Rainfall Anomaly Index (RAI). Trends were identified in two of three weather stations investigated. Positive precipitation trends were found in the spring and winter for Lages, and in the spring and summer for São Joaquim. Also, there is a trend of increase in the RX1, RX2 and RX3 frequencies and an increase in positive anomalies in the last decade for these stations. There are no statistically significant trends in the precipitation of Campos Novos, which may be associated with the short series of available data for the analysis. The occurrence of El Niño phenomenon with moderate to strong intensity was usually associated with the occurrence of positive precipitation anomalies and the La Niña phenomenon was related to the occurrence of negative anomalies. However, the influence of La Niña in the periods of negative anomaly has been reduced since the beginning of the 21st century.

Ano

2018

Creators

Sá,Eder Alexandre Schatz Moura,Carolina Natel de Padilha,Victor Luís Campos,Claudia Guimarães Camargo

Investigating the leaching properties of MBT wastes and composts from aerobic/anaerobic processes

Abstract This work assessed and compared the leaching properties of two types of compost and stabilized waste from a mechanical-biological treatment (MBT) plant. The first type of compost and the MBT waste were produced by aerobic treatments, while the second type of compost was generated from a combination of anaerobic and aerobic biodegradation processes. Both static-batch leaching tests, carried out applying a single liquid to solid (L/S) ratio equal to 10 L kg-1, and dynamic column percolation tests, investigating constituents release as a function of different L/S ratios, were performed. The three materials were also characterized in order to investigate their biological stability degree, organic matter content, and metals total content. As expected, due to the differences in feed input waste or treatment conditions, the three types of samples showed different characteristics and leaching concentrations. However, the leaching behavior of the three types of treated materials presented similar trends of dissolved organic carbon (DOC) and metals (Cu, Ni, Pb, Zn) leaching as a function of the L/S ratio. A screening model proposed and developed for MBT waste in a previous study, which allows the description DOC release as a function of the L/S ratio, was applied and discussed. The comparison of model predictions with the experimental leaching data highlighted that for all three samples the screening model describes quite well the release trends of metals.

Ano

2018

Creators

Lombardi,Francesco Chiara,Di Lonardo Maria Lieto,Alessio Sirini,Piero

Social and environmental innovations of Brazilian companies

Abstract This paper focuses on the social and environmental innovations of Brazilian companies, rather than on merely economic innovations. These innovations are discussed within the context of sustainability. Data were collected via a qualitative and descriptive study from the annual Guia Exame de Sustentabilidade magazine (2014 Edition). The magazine stated that 228 companies responded to the questionnaire. Of these, 61 companies stood out in Brazil for their policies and practices in sustainability and had their results published. The social innovations were geared towards meeting the needs of the surrounding communities. Environmental innovations appeared in greater numbers, connoting a higher stage of attention and interest from Brazilian companies. Environmental innovations were intended to evolve or improve processes and products and to reduce the consumption of resources.

Ano

2018

Creators

Machado Junior,Celso Souza,Maria Tereza Saraiva de Bazanini,Roberto Mantovani,Daielly Melina Nassif Furlaneto,Cristiane Jaciara

Surface albedo in different land-use and cover types in Amazon forest region

Abstract Albedo is the portion of energy from the Sun that is reflected by the earth's surface, thus being an important variable that controls climate and energy processes on Earth. Surface albedo is directly related to the characteristics of the Earth’s surface materials, making it a useful parameter to evaluate the effects of original soil cover replacement due to human occupation. This study evaluated the changes in the surface albedo values due to the conversion of vegetation to other land uses and to analyze the applicability of the use of albedo in the spatial delimitation of land-use classes in the transitional region between the Cerrado and Amazon biomes. Surface albedo measurements were obtained from processing of Landsat Thematic Mapper data in the Geographic Information System (GIS), and land-use information were collected using Google Earth high-resolution images. The results show that human activities such as the cultivation of crops and burning have contributed substantially to variations in the surface albedo, and that albedo estimates from Landsat imagery have the potential to help in the recognition and delimitation of features of land use and cover.

Ano

2018

Creators

Faria,Thiago de Oliveira Rodrigues,Thiago Rangel Curado,Leone Francisco Amorim Gaio,Denilton Carlos Nogueira,José de Souza

Production of energy (biodiesel) and recovery of materials (biochar) from pyrolysis of urban waste sludge

Abstract Safe disposal of sewage sludge is one of the most pressing issues in the wastewater treatment cycle: at the European Union level, sludge production is expected to reach 13 Mt by year 2020. Sludge disposal costs may constitute up to, and sometimes above, 50% of the total cost of operation of a WWTP, and contribute to over 40% of its GHGs emissions. The most common disposal options at the moment are landfilling, disposal in agriculture (about 40% EU-wide), incineration or co-incineration, and use in the industrial production of bricks, asphalts and concrete. Sewage sludge, however, still contains beneficial resources such as nutrients, that can be recovered through specific processes (e.g. precipitation as struvite) and energy, recoverable through a variety of approaches. Microwave-assisted pyrolysis of urban waste sludge was applied for the production of oil, (Syn)gas, and biochar that were afterwards characterized and compared to mainstream alternative fuels (biodiesels) and other material recovery options. Sustainability issues related to the production of biodiesel/biochars from urban wastewater treatment sludge are also discussed. The paper shows that waste urban sludge can indeed be a full component of the urban circular economy by allowing, if properly processed, recovery of energy resources at multiple levels: bio-oils (biodiesel), syngas and bio-char, all having definite advantages for final residues use and disposal. Biodiesel, in particular, allowing energy recovery as liquid fuel, offers a much more flexible and efficient utilization.

Ano

2018

Creators

Callegari,Arianna Hlavinek,Petr Capodaglio,Andrea Giuseppe

Characterization of controlled landfill leachate from the city of Guaratinguetá - SP, Brazil

Abstract This research evaluated the physicochemical parameters of a leachate sample from a controlled landfill in the city of Guaratinguetá-SP. The evaluation was conducted using spectrometric and spectrophotometric methods in order to assess the formation of persistent compounds. The selection of parameters was based on the CETESB Article 18 and CONAMA 357/05 Article 34, as well as organic characterization methods, such as FTIR, NMR (1H-NMR, 13C-NMR and APT), GC-MS, molar mass distribution and elemental analysis (CHN). Chemical and physical stability were also verified. The ammoniacal nitrogen concentration is 20 times greater than tolerance limit established by law (20 mg L-1). The Ba and Ni presented concentrations above those permitted by the legislation (CETESB Article 18 and CONAMA 357/05 Article 34). Those values of chemical oxygen demand (COD) and total organic carbon (TOC) were 1013 mg L-1 and 286 mg L-1, respectively. It was not possible to determine the biochemical oxygen demand (BOD) of slurry sample. In this sense, the biodegradability parameter for the slurry studied was Non-Determinable (ND), indicating that the organic matter of the slurry studied is recalcitrant. Recalcitrant humic substances of landfill leachate the present low polydispersity. These refractory acids play a detached role in carrying pollutants in the environment with regard to carrying toxic metals and pesticides. Finally, it was possible to verify that the humic acids’ complexing capacity indicates that hydroxyl and carboxyl groups may exist in larger quantities than the nitrogen and sulfur groups. Further, the high content of metals may indicate that the waste was not properly separated.

Ano

2018

Creators

Peixoto,André Luis de Castro Salazar,Rodrigo Fernando dos Santos Barboza,Jayne Carlos de Souza Izário Filho,Hélcio José

The historical influence of tributaries on the water and sediment of Jacuí’s Delta, Southern Brazil

Abstract The high population density in a metropolis leads to socio-environmental impacts that directly affect local water resources. This work evaluated the historical data (between 2000 and 2014) of water and sediment monitoring in the Jacuí’s Delta region and analyzed the relationship between these sites. Seven monitoring sites around the Jacuí's Delta were evaluated: the outflow of the rivers Jacuí, Caí, Sinos, and Gravataí; the channels Ilha da Pintada and Navegantes; and Lake Guaíba. Water data were evaluated for: air and water temperature; depth; pH; electrical conductivity; transparency; turbidity; dissolved oxygen; biochemical oxygen demand; phosphorus; nitrogen; total residues; and escherichia coli. Sediment were evaluated for pseudo-total concentrations of metals (Al, Fe, Ca, Mn, Ba, V, Zn, Cu, Pb, Cr, Ni, Co, Li, Be, Cd, Hg, As, and Ag). The quality of water and sediment in the Jacuí's Delta are linked with the tributaries and priority flows of the channels. The historical data of water and sediment around the Jacuí's Delta shows the influence of the tributaries with low quality in the downstream points. The pollution of the rivers Caí, Sinos, and Gravataí negatively affects the environmental quality of the channel Navegantes and Lake Guaíba (catchment points to water supply). The water in those sites presents reductions in dissolved oxygen and high values of coliforms, and the sediment shows high concentrations of metal Zn, Pb, Cr, and Hg. Despite the reduction in Pb and Hg values in the sediment over the past years, pollution from the tributary rivers still persists.

Ano

2018

Creators

Andrade,Leonardo Capeleto de Andrade,Rodrigo da Rocha Camargo,Flávio Anastácio de Oliveira

Segregation of solid waste from a fish-processing industry: a sustainable action

Abstract Segregation techniques represent a sustainable alternative to minimize wastes of raw material in processing industries. This study considered the premise; its purpose was to use segregation techniques to determine the theoretical removal rate of solid compounds present in processing effluents, in order to support the sustainable development of the fish industry. The removal rates obtained for different treatments were evaluated for the parameters: total solids, organic matter and oils and greases, and the efficiency of the segregation of the effluent streams in the different stages of fish processing was evaluated through descriptive statistical analysis. The segregation recovered from 31% to 70% of total solids; from 15% to 97.50% of organic matter, and from 10% to 63% of oils and greases. These results indicates that the raw material can be used in new products, leading to reduced final-effluent concentration.

Ano

2018

Creators

Silva,Yeda dos Santos Naval,Liliana Pena

Assessment of the water quality and trophic state of the Ribeirão Guaraçau Watershed, Guarulhos (SP): a comparative analysis between rural and urban areas

Abstract The urbanization process through which large urban centers have been passing has affected drastically the availability and especially the quality of water. The Ribeirão Guaraçau Watershed, located in the northern part of the Guarulhos municipality, includes rural and urban areas of different land-use classes. The goal of this study is to assess the water quality and to diagnose the eutrophication stage of the surface waters of the Ribeirão Guaraçau, the main water course of the Ribeirão Guaraçau Watershed. To assess environmental quality, physical-chemical analyses (temperature, pH, turbidity, conductivity, and total phosphorus) and microbiological analyses (E. coli) were carried out during a period of 12 months. The Trophic State Index (TSI) was used to ascertain the environmental degradation conditions of lotic and lentic environments. The surface waters of the Ribeirão Guaraçau in the rural area are already compromised, with worsening of the water quality upstream indicated by high total phosphorus and E. coli caused by fecal contamination due to lack of basic sanitation in the region. Characteristic sites of the rural areas already present signs of degradation with trophic levels varying from oligotrophic to hypereutrophic. The need to provide sewage collectors and sewage treatment systems at the Bonsucesso Sewage Treatment Station, inaugurated in 2011, and the control of the occupation in areas that produce good quality water is paramount.

Ano

2018

Creators

Vargas,Reinaldo Romero Barros,Márcia da Silva Saad,Antonio Roberto Arruda,Regina de Oliveira Moraes Azevedo,Fernanda Dall'Ara

Effects of different operating conditions on total nitrogen removal routes and nitrous oxide emissions in a lab-scale activated sludge system

Abstract This study sought to determine the effects of different operating conditions, such as variable organic loading, different sludge retention times (SRTs) and airflow rates, limited dissolved oxygen (DO) concentrations and ammonium (NH4 +) shock loading on total nitrogen (TN) removal routes and nitrous oxide (N2O) emissions in a lab-scale activated sludge system. Short SRT (5 days) combined with very low DO levels (0.5 mg L-1) were responsible for lower TKN oxidation efficiencies and, consequently, negligible NO2 - accumulation rates. These results suggest that nitrification efficiency was hampered by the oxidation of organic matter, with a large part of TN removed by sludge waste process. As the SRT increased (from 5 to 10 days) and DO was set to 1.0 mg L-1, TKN oxidation rates and NO2 - accumulation reached their maxima, which are thought to be the optimal conditions for both organic matter oxidation and partial nitrification. Under these conditions, gas transfer to the atmosphere became the preferential route for TN removal instead of incorporation into the sludge waste. However, N2O contribution is estimated as less than 5.6% (with respect to TN in the influent). Insufficient aeration and stress conditions (such as NH4 + shock loading) can cause limited DO conditions and NO2 - accumulation, leading to higher amounts of emitted N2O. Therefore, the adequate control of DO concentrations is a key factor to avoid NO2 - accumulation and consequently high N2O emissions.

Ano

2018

Creators

Ribeiro,Renato Pereira Kligerman,Débora Cynamon Mello,William Zamboni de Silva,Denise da Piedade Correia,Renatah da Fonseca Oliveira,Jaime Lopes da Mota

Use of agricultural and agroindustrial residues as alternative adsorbents of manganese and iron in aqueous solution

Abstract The increase in the volume of agricultural and agroindustrial waste, associated with improper disposal, is a growing worldwide problem. The recovery of those residues is of crucial importance, since it reduces environmental impacts, protects public health, and allows the addition of value to the materials. One of the ways of exploiting adsorbents is related to the capacity of some wastes to be used as alternative adsorbents in the efficient removal of microcontaminants in aqueous systems. This work assessed the use of agricultural and agroindustrial residues: maize straw, wheat straw, soybean straw and soybean hulls for the production of alternative adsorbents to remove iron (Fe) and manganese (Mn) in water. For each residue investigated, two different polymers were obtained for use as adsorbents, a natural polymer (cellulose/lignin) and an EDTA-modified polymer (ethylenediaminetetraacetic acid). The adsorbents were characterized through FTIR (Fourier transform infrared spectroscopy) and nitrogen content. To evaluate the efficiency of the adsorbents, kinetic tests in batch mode and determination of Lagergren pseudo-first and pseudo-second order kinetic constants were performed. The results found that the modified polymer obtained from soybean hulls (SHE) showed increased Fe (96%) and Mn (88%) removal rate, in which the pseudo-second order kinetic model presented closer results between the experimental adsorption rates and the calculated ones for the two microcontaminants under study. In general, the modified soybean hulls proved to be a promising alternative adsorbent for the removal of iron and manganese in water treatment.

Ano

2018

Creators

Furlan,Fernanda Lansa Consolin Filho,Nelson Consolin,Marcilene Ferrari Barriquello Gonçalves,Morgana Suzsek Valderrama,Patrícia Genena,Aziza Kamal

Determination of carbamazepine and diazepam by SPE-HPLC-DAD in Belém River water, Curitiba-PR/Brazil

Abstract This work sought to determine the two psychotropic drugs most commonly released by Psychosocial Care Centers (CAPS) into urban river waters (Belém sub-basin, Curitiba, PR, Brazil). A simple analytical method using SPE followed by a HPLC-DAD was developed and validated. Strata-X® cartridges were used to extract (carbamazepine) CZ and diazepam (DZ) from water and SPE conditions were optimized by 23 factorial design. The validated method was specific for target compounds; correlation coefficients were above 0.9998, recovery between 85.8 and 98.4% and precision below 6.60% (RSD, n=3). This method was successfully applied to analyze river samples and pollution hotspots were identified. The CZ and DZ concentrations found ranged from 0.670 to 0.856 µg L-1 and from LOQ to 0.763 µg L-1, respectively, and confirmed that drug consumption is directly related to river pollution in the studied region.

Ano

2018

Creators

Böger,Beatriz Amaral,Bianca do Estevão,Priscila Lagner da Silveira Wagner,Ricardo Peralta-Zamora,Patricio Guillermo Gomes,Eliane Carneiro