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Evidence for chemical binding of proteinaceous materials to humic acids as a means for their preservation in the environmentHsu, Pang-Hung 29 September 2004 (has links)
No description available.
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Aspects of aquatic CO photoproduction from CDOMStubbins, Aron Paul January 2002 (has links)
No description available.
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Uranium associations and migration behaviour at the Needle's Eye natural analogue site in SW ScotlandXu, Xiaolu January 2015 (has links)
This thesis investigated uranium (U) migration behaviour at the Needle‟s Eye natural analogue site, located close to Southwick Water, South West Scotland. The results of this study are important for the prediction of U behaviour in the far-field environments of nuclear waste repositories over long time-scales. The Needle‟s Eye natural analogue site was selected because the processes involved in U mobilisation, the direction of water flow and the extent of retention of uranium in peaty soils had already been identified. To this end, previous results demonstrated that groundwater passing through the mineralisation oxidized U and transported it to the peaty area, where 80-90% of the released U has been retained. Sequential extraction of the peaty soils indicated that more than 90% of the solid phase U was bound to the organic fraction. However, in-depth characterisation of U associations within the soil porewaters and the peaty soils at this site was lacking. Therefore, the processes controlling the migration of uranium within this organic-rich system were the main focus of this study. There were five sampling trips carried out from 2007-2011, in which cave drip waters, bog waters and surface soil and soil core samples were selectively collected for analysis by a range of methods described below. The cave drip waters emerging from the mineralisation were oxidizing and slightly alkaline (7.6-7.8), U was mainly in truly dissolved (<3 kDa) forms (Ca2UO2(CO3)30, CaUO2(CO3)32- and UO2(CO3)22-). It is known that the formation of the ternary Ca-UVI-CO3 complexes inhibits the reduction of U and so it is likely that it is UVI that is present within the peaty soils and their associated porewaters. Sampling trip 1 quantified the U concentrations in cave waters and soil core porewaters. By 30 m from the cave, U concentrations in the soil porewaters had decreased by a factor of ~10. Ultrafiltration fractionated the colloidal fraction (3 kDa-0.2 μm) into large (100 kDa-0.2 μm), medium (30-100 kDa) and small (3-30 kDa) colloidal fractions. It was found that U was mainly associated with the large colloid (100 kDa-0.2 μm) but, with increasing distance from the mineralisation, the U distribution became bimodal with both large and small fractions being equally important. Iron (Fe) was exclusively associated with the large colloid fraction in the peaty soil porewaters. Gel electrophoresis and gel filtration, applied to study the interactions of U (and other elements) with humic substances (HS), showed that the associations were quite uniform with increasing depth of the cores and increasing distance from the U mineralisation. Uranium (and other elements including Fe) was associated with the largest humic molecules. Sampling trip 2 involved collection of three more soil cores and ultrafiltration again fractionated the total dissolved porewater into large, medium and small colloids. This time, the truly dissolved (<3 kDa) fraction was also analysed. Again, U was mainly associated with the large colloidal (100 kda-0.2 μm) fraction. With increasing distance and increasing depth, U was still predominantly associated with the large colloidal fraction, but the importance of the truly dissolved (<3 kDa) phase could not be neglected. At the same time, Fe was also mainly associated with the large colloidal fraction. The remainder of the experimental work on samples from trip 2 focused on determining the importance of U associations with both Fe and humic components of the solid phase. Sequential extraction of the whole soil mainly targeted different iron phases and found that U was mainly released in the sodium acetate and sodium dithionite solutions, which indicated U was associated with (i) Fe carbonates; and (ii) crystalline Fe oxides (e.g. goethite, hematite, and akaganetite). However, very little Fe was extracted in the “carbonate-bound” fraction and separate experiments showed that U was not associated with Fe carbonates but instead had been released from the surfaces of HS and humic-bound Fe surfaces. XRD spectroscopy showed that mineral compositions were in reasonable agreement with the sequential extraction results and SEM-EDX analysis indicated that U in the soil was generally not present in crystalline form, as only two particles with high U content were found after 4-hour searching. Exhaustive extraction of HS showed that >90% U was associated with organic substances, in agreement with previous work and novel experiments involving gel electrophoresis in conjunction with sequential extraction was used to study the relationships between U, Fe and the HS. It was demonstrated that ~20-25% U was weakly held by the HS or at humic-bound Fe surfaces, ~45% was incorporated into crystalline Fe oxides which were intimately associated with HS and the remainder was in the form of strong U-CO3-humic complexes. In sampling trip 3, U migration behaviour in the soil porewaters was the focus. A 30-m transect line, comprising seven0-5 cm soil samples, starting at the cave and passing through the peaty area towards the Southwick Water, was established. Soil porewaters from these surface soils were fractionated into colloidal (3 kDa-0.2 μm) fraction and truly dissolved (<3 kDa) phase. There was a major change in U speciation, from Ca2UO2(CO3)3 0,CaUO2(CO3)32- and UO2(CO3)22- in the truly dissolved fractions of waters close to the cave to a predominant association with the highly coloured colloidal fractions as soon as the boggy area was reached. With distance through the boggy area, it was clear that the colloidal U was being incorporated into the solid phase since porewater concentrations had decreased ~100-fold by 30 m from the cave. Ultrafiltration in conjunction with acetate extraction was then used to extract U from the porewater colloids isolated from a soil core (20 m from cave). In the organic-rich portion of the core (0-30 cm), ~60-70% U was colloidally associated and ~85-95% of this U was extracted from the colloidal fraction. This indicated that the interactions between U and the porewater colloids were weak. In sampling trip 4, U associations in the porewater colloids were still the main focus. Gel filtration of porewater colloids confirmed that U, Fe and humic colloids were intimately associated. It was concluded that although U in the cave drip water was mainly in truly dissolved forms, weak U----humic/Fe colloids were formed immediately when U entered the peaty area. In sampling trip 5, results for soil core porewaters showed that Fe in the whole core was mainly in the form of FeII. Thus strongly reducing conditions prevailed through the core which was situated within the peaty area. Combining the results from the five sampling trips, three zones within the peaty area were distinguished. Zone I was characterised by extremely high concentrations of dissolved HS and this was where the change in U speciation from dissolved to colloidal forms took place. Zone II contained most of the soil cores collected during this study and was characterised by strongly reducing conditions and moderate concentrations of HS. Colloidal U was removed to the solid phase as waters flow through this area. Zone III marks the transition to the saltmarsh. Focusing on Zone II, a conceptual model of U behaviour was developed: upon entering the peaty area, U is weakly held by very large humic-Fe colloids. These colloids are removed to the solid phase and over time the associations of U are transformed; some becomes incorporated into stable humic-bound crystalline oxides as a result of redox cycling of Fe, some becomes strongly complexed to HS and the remainder is weakly held by the HS and/or humic-bound Fe surfaces. The crystalline Fe oxides were transformed to Fe sulfides below 30 cm depth but the associated U was not transferred to these sulfides. Instead the weak associations became more important. In the wider context, since only UVI forms soluble complexes with acetate, UVI does not appear to be reduced even under the strongly reducing conditions encountered within waterlogged organic-rich soils. Initial interactions between UVI and porewater colloids appear to be weak but stronger interactions such as incorporation into Fe phases and complexation by HS occur once the colloids and associated U are removed to the solid phase. Waterlogged organic-rich soils appear to be a long-term sink for U but changing climatic conditions leading to the drying out of such soils may ultimately release U in association with smaller, more mobile organic-rich colloids.
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Distribuição e caracterização da labilidade relativa de cobre, chumbo e mercúrio em amostras de sedimentos e substâncias húmicas extraídas de sedimentos coletados em mananciais com diferentes tipos de águas da Bacia Amazônica /Rocha, Bruno Cesar Prior. January 2017 (has links)
Orientador: André Henrique Rosa / Banca: Clóvis Augusto Ribeiro / Banca: Leandro Cardoso de Morais / Banca: Eny Maria Vieira / Banca: Ézio Sargentini Junior / Resumo: Neste trabalho caracterizou-se a distribuição e disponibilidade de cobre, chumbo e mercúrio totais em águas superficiais, substâncias húmicas e frações granulométricas de sedimentos coletados em mananciais dos três diferentes tipos de águas da bacia amazônica, ou seja, rios de água branca (barrenta), rios de água preta e rios de água clara. As amostras foram coletadas durante período de cheia e seca entre 2014 e 2015, nos reservatórios da Usina Hidredrétrica de Jirau (Rio Madeira - RO - água branca), da Usina Hidrelétrica de Cana Brava (Rio Tocantins - GO) e no baixo Rio Negro - AM. As concentrações das espécies analisadas estão de acordo com o disposto na Resolução CONAMA no 454/2012, a qual estabelece as diretrizes gerais e os procedimentos mínimos para a avaliação do material a ser dragado em águas, preconizando para Cu 35,7 e 197; para Pb 35 e 91,3; e para Hg 0,17 e 0,486 mg kg-1 em referência aos níveis 1 e 2, respectivamente. Os maiores valores médios de concentração de cobre total foram no rio com tipo de água branca (rio Madeira) em seguida no rio com tipo de água clara (rio Tocantins) e rio com tipo de água preta (rio Negro). Podendo-se assim estabelecer a seguinte ordem decrescente de concentração média de Cu nos sedimentos: água branca> água clara> água preta. Para chumbo, os maiores valores médios de concentração foram no rio com tipo de água branca em seguida no rio com tipo de água clara e rio com tipo de água preta. Pode-se estabelecer a seguint... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, the distribution and availability of copper, lead and mercury in surface waters, humic substances and granulometric fractions of sediments collected from the three different types of waters of the Amazon basin, ie white water rivers (muddy), Rivers of black water and rivers of clear water. The samples were collected during the flood and dry period between 2014 and 2015, in the reservoirs of the Jirau Hydroelectric Plant (Rio Madeira - RO - white water), the Cana Brava Hydroelectric Power Plant (Rio Tocantins - GO) and the lower Rio Negro - AM. The concentrations of the species analyzed are in accordance with CONAMA Resolution 454/2012, which establishes the general guidelines and minimum procedures for the evaluation of the material to be dredged in waters, recommending for Cu 35,7 and 197; For Pb 35 and 91.3; And for Hg 0.17 and 0.486 mg kg -1 in reference to levels 1 and 2, respectively. The highest values of total copper concentration were in the river with a white water type (Madeira river), followed by a river with a clear water type (Tocantins river) and a river with a black water type (Rio Negro). It is possible to establish the following order of decreasing average concentration of Cu in the sediments: white water> clear water> black water. For lead, the highest values of concentration were in the river with white water type then in the river with clear water type and river with type of black water. The following order of average Pb conc... (Complete abstract click electronic access below) / Doutor
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Obtenção e caracterização de biofertilizantes a partir de técnicas de compostagem sólida / Production and characterization of biofertilizers from solid technical compostingForgerini, Daniely 16 March 2012 (has links)
A matéria orgânica (MO) encontrada no solo pode ser dividida em dois compartimentos, o primeiro é composto pela fração não humificada, representada pelos compostos orgânicos com categoria bioquímica definida (proteínas, açúcares, ceras, graxas, resinas) e o segundo é formado pelas substâncias húmicas (SH), produtos da intensa transformação dos resíduos orgânicos pela biomassa e polimerização dos compostos orgânicos. A MO funciona como um reservatório de nutrientes do solo, sendo então responsável pela fertilidade deste. O cultivo intensivo tende a reduzir a quantidade de MO. A utilização de fertilizantes orgânicos, também chamados de biofertilizantes, é considerada uma alternativa sustentável de recuperar a fertilidade do solo, pois além de repor adequadamente os nutrientes perdidos ainda reutiliza resíduos orgânicos que se dispensados na natureza causariam impactos ambientais negativos. Neste trabalho foram obtidos dois biofertilizantes de esterco bovino, utilizando os processos de vermicompostagem e o de compostagem sólida acrescentada de microrganismos provenientes do produto comercial denominado Microgeo®. Para fins de caracterização e comparação, foram realizadas análises físico-químicas nesses biofertilizantes, cujos resultados demonstraram que ambos se encontram dentro dos parâmetros estabelecidos pelo Ministério de Agricultura Pecuária e Abastecimento (MAPA), para a comercialização de fertilizantes orgânicos e que houve uma maior incorporação de nutrientes no esterco após a realização dos dois processos. Para a determinação do grau de humificação dos biofertilizantes, foram utilizadas as técnicas de espectroscopia de fotoacústica e ultravioleta - visível, que apresentaram a mesma tendência de absorção, tendo absorção máxima, próximo a 300nm, e a técnica de espectroscopia de infravermelho que apresentou bandas de absorção tipicamente encontradas em estruturas de ácidos húmicos, para ambos os biofertilizantes. Foram realizados também, testes de germinação com os biofertilizantes obtidos, utilizando sementes de alface, que apresentaram boa germinação e bom crescimento de biomassa para os dois biofertilizantes. Concluiu-se então com este trabalho que os dois produtos obtidos apresentam características similares e podem ser utilizados com eficiência na recuperação da fertilidade de solos. / The organic matter (OM) in the soil can be divided into two compartments. The first is composed of non humified fraction, represented by the organic compounds with defined biochemical category (proteins, sugars, waxes, greases, resins) and the second compartment is formed by humic substances, which are products of intense transformation of the organic matter and biomass by polymerization of the organic compounds. The OM acts as a reservoir of soil nutrients and it is responsible for soil fertility. The intensive agriculture tends to reduce this amount of OM. The use of organic fertilizers, also called biofertilizers, is considered a sustainable alternative to restore soil fertility, as well as restore lost nutrients properly by reusing organic waste which if released in the environment could cause negative environmental impacts. In this work two biofertilizers were obtained from cattle manure, using the vermicomposting and solid composting processes. In the solid composting process it was added microorganisms from the commercial product called Microgeo®. For purposes of characterization and comparison, physical-chemical analysis were performed in these biofertilizers, showing that both are within the parameters established by the Ministry of Agriculture Livestock and Supply, for the marketing of organic fertilizers and a greater incorporation of nutrients in the cattle manure after the completion of the two processes occurs. To determine the degrees of humification of the produced biofertilizers both photoacoustic and ultraviolet - visible spectroscopic techniques were used, showing the same trend of absorption and maximum absorption near 300 nm. The infrared spectroscopy which showed absorption bands typically found in structures of humic acids for both fertilizers was also used. The germination tests were performed using lettuce seeds planted in soil mixed with the biofertilizers. The results pointed out to a good germination and growth of biomass for two biofertilizers. The conclusion of this work was that both biofertilizers have similar characteristics and both can be used effectively in the recovery of soil fertility.
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Reguladores de crescimento e adubação orgânica no estresse hídrico da cana-planta / Growth regulators and organic fertilization in the water stress of sugarcaneMalvestitti Neto, Antonio 04 October 2018 (has links)
No presente trabalho, objetivou-se estudar o uso de biorregulador sintético, cama de frango e torta de filtro no desenvolvimento e produtividade da cana-de-açúcar em situação de estresse hídrico. O experimento foi implantado e conduzido no município de Analândia/SP. O delineamento experimental utilizado foi o de blocos ao acaso, com 9 tratamentos, distribuídos aletoriamente em 5 Repetições, totalizando 45 parcelas. O biorregulador utilizado é constituído de três grupos químicos de hormônios sintéticos: auxina (0,005%), giberilina (0,005%) e cinetina (0,009%), e os tratamentos foram: 1 controle sem biorregulador, 2 biorregulador no plantio, 3 biorregulador no rebaixamento da entrelinha, 4 biorregulador no crescimento final, 5 biorregulador no plantio e crescimento final, 6 biorregulador no plantio e rebaixamento da entrelinha, 7 biorregulador no rebaixamento da entrelinha e crescimento final, 8 torta de filtro sem biorregulador, 9 cama de frango sem aplicação biorregulador. O tratamento Stimulate aplicado no sulco de plantio, apresentou a maior produtividade, com 129,93 t ha-1. Os tratamentos cama de frango e torta de filtro não se diferenciaram dos demais em produtividade. A aplicação de Stimulate e compostos orgânicos não interfiriram nos parâmetros tecnológicos. A utilização do regulador de crescimento mostrou-se eficiente. / In the present work, the objective was to study the use of synthetic biorregador, litter of chicken and filter cake in the development and productivity of sugarcane in a situation of water stress. The experiment was implemented and conducted in the city of Analândia / SP. The experimental design was used for the use of blocks, with 9 treatments, distributed in 5 replications, totaling 45 plots. The bioregulator used consisted of three chemical groups of synthetic hormones: auxin (0.005%), giberilin (0.005%) and kinetin (0.009%), and treatments were: 1 control without bioregulator, 2 bioregulator at planting, 3 bioregulator lowering of the interweave, 4 bioregulator in the final growth, 5 bioregulator in the planting and final growth, 6 bioregulator in the planting and lowering of the interweave, 7 bioregulator in the lowering of the interweave and final growth, 8 filter cake without bioregulator, 9 chicken bed without bioregulator application. The Stimulate treatment applied in the planting groove, presented higher productivity, with 129.93 t ha-1. The chicken bed and filter cake treatments did not differ from the others in productivity. The application of Stimulate and compound vegetables in interfered in the technological parameters. The use of growth regulator was eficiente.
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Reguladores de crescimento e adubação orgânica no estresse hídrico da cana-planta / Growth regulators and organic fertilization in the water stress of sugarcaneAntonio Malvestitti Neto 04 October 2018 (has links)
No presente trabalho, objetivou-se estudar o uso de biorregulador sintético, cama de frango e torta de filtro no desenvolvimento e produtividade da cana-de-açúcar em situação de estresse hídrico. O experimento foi implantado e conduzido no município de Analândia/SP. O delineamento experimental utilizado foi o de blocos ao acaso, com 9 tratamentos, distribuídos aletoriamente em 5 Repetições, totalizando 45 parcelas. O biorregulador utilizado é constituído de três grupos químicos de hormônios sintéticos: auxina (0,005%), giberilina (0,005%) e cinetina (0,009%), e os tratamentos foram: 1 controle sem biorregulador, 2 biorregulador no plantio, 3 biorregulador no rebaixamento da entrelinha, 4 biorregulador no crescimento final, 5 biorregulador no plantio e crescimento final, 6 biorregulador no plantio e rebaixamento da entrelinha, 7 biorregulador no rebaixamento da entrelinha e crescimento final, 8 torta de filtro sem biorregulador, 9 cama de frango sem aplicação biorregulador. O tratamento Stimulate aplicado no sulco de plantio, apresentou a maior produtividade, com 129,93 t ha-1. Os tratamentos cama de frango e torta de filtro não se diferenciaram dos demais em produtividade. A aplicação de Stimulate e compostos orgânicos não interfiriram nos parâmetros tecnológicos. A utilização do regulador de crescimento mostrou-se eficiente. / In the present work, the objective was to study the use of synthetic biorregador, litter of chicken and filter cake in the development and productivity of sugarcane in a situation of water stress. The experiment was implemented and conducted in the city of Analândia / SP. The experimental design was used for the use of blocks, with 9 treatments, distributed in 5 replications, totaling 45 plots. The bioregulator used consisted of three chemical groups of synthetic hormones: auxin (0.005%), giberilin (0.005%) and kinetin (0.009%), and treatments were: 1 control without bioregulator, 2 bioregulator at planting, 3 bioregulator lowering of the interweave, 4 bioregulator in the final growth, 5 bioregulator in the planting and final growth, 6 bioregulator in the planting and lowering of the interweave, 7 bioregulator in the lowering of the interweave and final growth, 8 filter cake without bioregulator, 9 chicken bed without bioregulator application. The Stimulate treatment applied in the planting groove, presented higher productivity, with 129.93 t ha-1. The chicken bed and filter cake treatments did not differ from the others in productivity. The application of Stimulate and compound vegetables in interfered in the technological parameters. The use of growth regulator was eficiente.
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Effects of algae (Isochrysis galbana) and humic acids on copper toxicity to polychaete (Hydroides elegans) larvaeWong, Nga Cheung 01 January 2005 (has links)
No description available.
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Obtenção e caracterização de biofertilizantes a partir de técnicas de compostagem sólida / Production and characterization of biofertilizers from solid technical compostingDaniely Forgerini 16 March 2012 (has links)
A matéria orgânica (MO) encontrada no solo pode ser dividida em dois compartimentos, o primeiro é composto pela fração não humificada, representada pelos compostos orgânicos com categoria bioquímica definida (proteínas, açúcares, ceras, graxas, resinas) e o segundo é formado pelas substâncias húmicas (SH), produtos da intensa transformação dos resíduos orgânicos pela biomassa e polimerização dos compostos orgânicos. A MO funciona como um reservatório de nutrientes do solo, sendo então responsável pela fertilidade deste. O cultivo intensivo tende a reduzir a quantidade de MO. A utilização de fertilizantes orgânicos, também chamados de biofertilizantes, é considerada uma alternativa sustentável de recuperar a fertilidade do solo, pois além de repor adequadamente os nutrientes perdidos ainda reutiliza resíduos orgânicos que se dispensados na natureza causariam impactos ambientais negativos. Neste trabalho foram obtidos dois biofertilizantes de esterco bovino, utilizando os processos de vermicompostagem e o de compostagem sólida acrescentada de microrganismos provenientes do produto comercial denominado Microgeo®. Para fins de caracterização e comparação, foram realizadas análises físico-químicas nesses biofertilizantes, cujos resultados demonstraram que ambos se encontram dentro dos parâmetros estabelecidos pelo Ministério de Agricultura Pecuária e Abastecimento (MAPA), para a comercialização de fertilizantes orgânicos e que houve uma maior incorporação de nutrientes no esterco após a realização dos dois processos. Para a determinação do grau de humificação dos biofertilizantes, foram utilizadas as técnicas de espectroscopia de fotoacústica e ultravioleta - visível, que apresentaram a mesma tendência de absorção, tendo absorção máxima, próximo a 300nm, e a técnica de espectroscopia de infravermelho que apresentou bandas de absorção tipicamente encontradas em estruturas de ácidos húmicos, para ambos os biofertilizantes. Foram realizados também, testes de germinação com os biofertilizantes obtidos, utilizando sementes de alface, que apresentaram boa germinação e bom crescimento de biomassa para os dois biofertilizantes. Concluiu-se então com este trabalho que os dois produtos obtidos apresentam características similares e podem ser utilizados com eficiência na recuperação da fertilidade de solos. / The organic matter (OM) in the soil can be divided into two compartments. The first is composed of non humified fraction, represented by the organic compounds with defined biochemical category (proteins, sugars, waxes, greases, resins) and the second compartment is formed by humic substances, which are products of intense transformation of the organic matter and biomass by polymerization of the organic compounds. The OM acts as a reservoir of soil nutrients and it is responsible for soil fertility. The intensive agriculture tends to reduce this amount of OM. The use of organic fertilizers, also called biofertilizers, is considered a sustainable alternative to restore soil fertility, as well as restore lost nutrients properly by reusing organic waste which if released in the environment could cause negative environmental impacts. In this work two biofertilizers were obtained from cattle manure, using the vermicomposting and solid composting processes. In the solid composting process it was added microorganisms from the commercial product called Microgeo®. For purposes of characterization and comparison, physical-chemical analysis were performed in these biofertilizers, showing that both are within the parameters established by the Ministry of Agriculture Livestock and Supply, for the marketing of organic fertilizers and a greater incorporation of nutrients in the cattle manure after the completion of the two processes occurs. To determine the degrees of humification of the produced biofertilizers both photoacoustic and ultraviolet - visible spectroscopic techniques were used, showing the same trend of absorption and maximum absorption near 300 nm. The infrared spectroscopy which showed absorption bands typically found in structures of humic acids for both fertilizers was also used. The germination tests were performed using lettuce seeds planted in soil mixed with the biofertilizers. The results pointed out to a good germination and growth of biomass for two biofertilizers. The conclusion of this work was that both biofertilizers have similar characteristics and both can be used effectively in the recovery of soil fertility.
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Adsorption of dissolved organic matter (DOM) containing humic and fulvic acid in aqueous solution using carbon nanotubesJung, Meng-Jia 10 July 2011 (has links)
Drinkable water sources (mainly including rivers, reservoirs, and groundwater) are almost universally polluted by organic substances. In Taiwan, the majority of water treatment plants ensure high-quality drinking water by using chlorine to control the growth of algae and microorganisms, thereby removing odors, tastes, ferric and manganese irons. However, these processes produce disinfection by-products (DBPs), such as Trihalomethanes (THMs) and Haloacetic acids. These DBPs contained in drinking water increase the risk of cancer in human body. Thus commercial carbon nanotubes (CNTs) were employed as adsorbents to study adsorption of humic acid (HA) and dissolved organic matter (DOM) in raw water.
Experiment results exhibited kinetic adsorption reached equilibrium about 120 minutes,the best selection in kinetic models evaluation, fitting models such as Modified Freundlich equation, Pseudo-1st-order equation and Pesudo-2nd-oder equation, is Modified Freundlch equation model. In addition, intraparticle diffusion equation model was fitted well and showed adsorption process was controlled with pore diffusion.The maximum adsorbed amounts of DOM onto SWCNTs was calculated by the Langmuir model at 25¢J, reaching 54.01 mg TOC / g which were much higher than that onto commercially available granular activated carbon (10.69 mg TOC / g).The maximum adsorbed amounts of HA onto CNTs was calculated by the Langmuir model at 25¢J, reaching 125.95 mg TOC / g which were much higher than that onto commercially availablepowdered activated carbon (42.37mg TOC / g).A favorable adsorption of single-wall carbon nanotubes was found when high initial concentration of DOM was adsorbed at low ion strength, low pH and low temperature .According to results of thermodynamic parameters indicated that the adsorption was spontaneously and an exothermic reaction.
The short contact time needed to reach equilibrium as well as the high adsorption capacity of DOM suggests that CNTs possess highly potential applications for DOM removal from raw water.In the future, we can combine nanotube technology with disinfection technology and apply such technique on the end of processing unit for design of either the domestic treatment facilities or small simple water treatment in drinking water. Thus our results in this work will enhance the new treatment technology of drinking water and improve the safety of the public health. Another possibility will be to promote the opportunity of marketing development in drinking water.
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