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Cesar Ricardo Teixeira Tarley - One of the best experts on this subject based on the ideXlab platform.
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synthesis and evaluation of different adsorbents based on poly methacrylic acid trimethylolpropane trimethacrylate and poly vinylimidazole trimethylolpropane trimethacrylate for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
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Synthesis and evaluation of different adsorbents based on poly(methacrylic acid–trimethylolpropane trimethacrylate) and poly(vinylimidazole–trimethylolpropane trimethacrylate) for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
Raquel Justo Da Fonseca - One of the best experts on this subject based on the ideXlab platform.
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synthesis and evaluation of different adsorbents based on poly methacrylic acid trimethylolpropane trimethacrylate and poly vinylimidazole trimethylolpropane trimethacrylate for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
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Synthesis and evaluation of different adsorbents based on poly(methacrylic acid–trimethylolpropane trimethacrylate) and poly(vinylimidazole–trimethylolpropane trimethacrylate) for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
Mariana Gava Segatelli - One of the best experts on this subject based on the ideXlab platform.
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synthesis and evaluation of different adsorbents based on poly methacrylic acid trimethylolpropane trimethacrylate and poly vinylimidazole trimethylolpropane trimethacrylate for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
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Synthesis and evaluation of different adsorbents based on poly(methacrylic acid–trimethylolpropane trimethacrylate) and poly(vinylimidazole–trimethylolpropane trimethacrylate) for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
Keyller Bastos Borges - One of the best experts on this subject based on the ideXlab platform.
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synthesis and evaluation of different adsorbents based on poly methacrylic acid trimethylolpropane trimethacrylate and poly vinylimidazole trimethylolpropane trimethacrylate for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
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Synthesis and evaluation of different adsorbents based on poly(methacrylic acid–trimethylolpropane trimethacrylate) and poly(vinylimidazole–trimethylolpropane trimethacrylate) for the adsorption of Tebuthiuron from aqueous medium
Reactive & Functional Polymers, 2015Co-Authors: Raquel Justo Da Fonseca, Mariana Gava Segatelli, Keyller Bastos Borges, Cesar Ricardo Teixeira TarleyAbstract:Abstract In the present study a new cross-linked copolymer poly(methacrylic acid–trimethylolpropane trimethacrylate) (named PMA) and poly(vinylimidazole–trimethylolpropane trimethacrylate) (named PVI) was synthesized through precipitation polymerization and applied to the adsorption of Tebuthiuron. Adsorbent materials were characterized by using FT-IR, SEM, TGA, textural data, and elemental analysis. Kinetic study showed that the Tebuthiuron adsorption was very quick and the equilibrium time was achieved at 20 min for both polymers. Experimental kinetic data for both polymers were very well described by the second-order kinetic model, thus indicating that Tebuthiuron adsorption involves chemical adsorption in different binding sites, which could control the reaction rate. Adsorption equilibrium data were better fitted to the dual-site Langmuir–Freundlich model, which recognizes the existence of two kinds of adsorption sites on the polymer surface ascribed to the presence of carboxyl and carbonyl groups from PMA and imidazole ring and carbonyl group from PVI. The maximum adsorption capacities of PMA and PVI were found to be 186.76 and 213.89 mg g − 1 , respectively, which are much higher than other adsorbents.
C A Spadotto - One of the best experts on this subject based on the ideXlab platform.
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variabilidade espacial do risco de contaminacao de aguas subterrâneas por Tebuthiuron em area de cana de acucar
Pesquisa Agropecuaria Brasileira, 2016Co-Authors: D A C Moraes, C A Spadotto, Anderson Antonio Da Conceicao Sartori, Celia Regina Lopes ZimbackAbstract:The objective of this work was to evaluate the groundwater contamination risk by Tebuthiuron in a sugarcane area, through spatial modeling, in the municipality of Sao Manuel, in the state of Sao Paulo, Brazil. The Araqua model was used to generate specific concentration estimates, considering simulations regarding different water table depths (100 and 200 cm) and irrigation depths (0 and 2,500 mm). As the estimated concentrations of Tebuthiuron did not show spatial dependence, the thematic maps of risk of groundwater contamination were obtained through the method of interpolation by the inverse distance. Considering all the simulations, it can be concluded that there would be no groundwater contamination by Tebuthiuron at the two depths of the water table, with or without irrigation. The interpolation of the estimated concentrations of Tebuthiuron in groundwater provides the spatialization and a quick view of the areas with higher contamination risk.
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espacializacao das estimativas de contaminacao de aguas subterrâneas por Tebuthiuron
IRRIGA, 2012Co-Authors: D A C Moraes, Celia Regina Lopes Zimback, C A SpadottoAbstract:O uso inadequado de defensivos agricolas pode levar a impactos ambientais relevantes, como a contaminacao de diversos compartimentos ambientais, sendo os mais vulneraveis, os compartimentos aquaticos. Nesse contexto, a espacializacao das estimativas de concentracao de defensivos agricolas na agua subterrânea fornece importantes subsidios para a tomada de decisao no gerenciamento e monitoramento do uso de defensivos agricolas. Assim, este trabalho teve por objetivo espacializar as estimativas de contaminacao de aguas subterrâneas por Tebuthiuron, considerando diferentes lâminas de irrigacao na Bacia do Rio Pardo, Pardinho-SP. As simulacoes realizadas com o sistema computacional ARAqua considerando as lâminas de irrigacao anuais de 0 mm, 200 mm e 400 mm. Tecnicas geoestatisticas foram utilizadas em conjunto com as simulacoes para obter a espacializacao dessas estimativas. Foram obtidos os mapas das estimativas de concentracao de defensivos agricolas na agua subterrânea pelo metodo de interpolacao por krigagem, sendo que estes indicaram as areas com maior potencial de contaminacao da agua subterrânea. Considerando todas as simulacoes pode-se concluir que nao houve risco de contaminacao da agua subterrânea por Tebuthiuron. As tecnicas de geoestatistica contribuiram fortemente para a espacializacao das estimativas de concentracao de defensivos agricolas na agua subterrânea.
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sorption degradation and leaching of Tebuthiuron and diuron in soil columns
Journal of Environmental Science and Health Part B-pesticides Food Contaminants and Agricultural Wastes, 2005Co-Authors: Marcus Barifouse Matallo, C A Spadotto, Luiz Carlos Luchini, Marco Antonio Ferreira GomesAbstract:Abstract A study in small outdoor lysimeters was carried out to determine the leaching of the herbicides Tebuthiuron and diuron in different soil types, using undisturbed soil columns. Soil sorption and degradation for both herbicides were also studied in the laboratory. The multi-layered AF (Attenuation Factor) model was evaluated for predicting the herbicides leaching in undisturbed soil columns. Tebuthiuron leached in greater amounts than diuron in both soils. Sorption was well represented by linear and Freundlich equations, however parameters from the linear equations were used in the AF model. In general, both herbicides presented very low sorption, with diuron presenting lower values of sorption coefficient than Tebuthiuron in the two soils. Chromatographic data indicated rapid late degradation of diuron and Tebuthiuron in both soil types at two different depths. Simple exponential equation was not able to represent degradation, thus a bi-exponential equation was used, and some model adjusting was n...
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ocorrencia do herbicida Tebuthiuron na agua subterrânea da microbacia do corrego espraiado ribeirao preto sp
Pesticidas: Revista de Ecotoxicologia e Meio Ambiente, 2001Co-Authors: Marco Antonio Ferreira Gomes, C A Spadotto, Vera Lucia LanchotteAbstract:Pretendeu-se mostrar que o herbicida Tebuthiuron, selecionado entre outros usados na cultura de cana-de-acucar, oferece risco de contaminacao para a agua subterrânea em funcao de suas caracteristicas fisico-quimicas, principalmente, quando aplicado em areas de recarga direta de aquiferos consideradas de alta vulnerabilidade natural. Assim, efetuou-se monitoramento do referido herbicida no periodo compreendido entre 1995 e 1999, coletando amostras de agua de poco semi-artesiano, com 53 metros de profundidade, localizado na microbacia do Corrego Espraiado, municipio de Ribeirao Preto/SP, Brasil, no qual tem sido frequente o uso do produto em questao. Para efeito de testemunha da amostra de agua foi considerado um poco semi-artesiano de profundidade semelhante, localizado cerca de tres quilometros de distância do poco objeto de monitoramento. Os resultados obtidos mostraram que o Tebuthiuron esta presente em todas as amostras analisadas, embora em concentracoes abaixo do nivel critico para padrao de potabilidade, conforme os limites mais restritivos estabelecidos pela Organizacao Mundial de Saude (para os pesticidas em uso e de 0,1 µg/L por pesticida e de 0,5 µg/L para pesticidas totais). Mesmo com os baixos valores de concentracao encontrados fica evidente que o Tebuthiuron esta atingindo a agua subterrânea podendo aumentar sua concentracao pela existencia de condicoes ambientais favoraveis a preservacao da molecula em profundidade (tais como baixa temperatura, baixa atividade biologica e ausencia de luz). Caso o nivel critico seja atingido, o risco de contaminacao poderia ser minimizado por meio da substituicao do Tebuthiuron por outro herbicida com menor mobilidade no perfil do solo. OCCURRENCE OF THE HERBICIDE Tebuthiuron IN GROUNDWATER OF ESPRAIADO CATCHMENT RIBEIRAO PRETO - SP (BRASIL) Abstract The herbicide Tebuthiuron, selected among others utilized in sugar-cane crop, shows groundwater contamination risk due to its physicochemical properties, mainly, when applied in direct recharge areas of aquifers considered of high natural vulnerability. In this context, the monitoring of this herbicide in the period of 1995 through 1999 was realized, by collecting water samples of aquifers 53 m depht, located in Espraiado catchment, Ribeirao Preto/SP (Brazil) in which the product has been extensively used. For blank assays it was utilized water samples collected similarly 3 Km away from the monitoring area. The results obtained showed that Tebuthiuron is present in all analyzed samples. Although in lower concentrations of the critical level for drinkable water, following the restrictive limits established by World Health Organization (for pesticides in use is 0,1 µg/L by pesticide and of 0,5 µg/L for total pesticides). Even if the low concentration values found it is evident that the Tebuthiuron affects the groundwater, and could enhance its concentration by favorable ambiental conditions for molecule preservation in deep water (such as low temperature, low biological activity and absence of light). The present scenary reflects contamination risk in case of reaching the critical level, which could only be minimized by the substitution of Thebuthiuron for other herbicide with lower soil mobility.
