Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano
Autor(a) principal: | |
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Data de Publicação: | 2019 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Manancial - Repositório Digital da UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/18819 |
Resumo: | Fluoride (Fˉ) is an element that is commonly present in groundwater, and that in excessive concentrations may make it unfit for consumption. Contamination of groundwater by fluoride ions may occur through natural processes or due to anthropic activity, with the release of fluoride-containing industrial waste. Excessive intake of fluoride may, in the long run, cause so-called dental and skeletal fluorosis. In addition, ingestion of excess fluoride can also, in severe cases, lead to neurological damage, Alzheimer's disease and cancer. That is why it is fundamental to the de-watering of groundwater for human supply. Adsorption is a prominent technique among the available methodologies for water defluoride, being one of the most efficient in terms of cost, design and operation. In this sense, the main goal of the present study was the application of adsorption to groundwater defluoride for human supply in the State of Rio Grande do Sul. Preliminary tests were carried out for the removal of fluoride from synthetic solutions 5 mg L-1, in which several adsorbent, commercial and alternative. A process of ultrasonic assisted synthesis of an adsorbent based on activated alumina modified with ZnCl2 (AA-ZnCl2) has been proposed. In the characterization step, the adsorbents adsorbents adsorbents adsorbents commercial powder without chemical modification (AACP) and AAZnCl2 were obtained, and BET, EDS scanning electron microscopy, diffraction analysis of Xrays and FT-IR. A procedure was performed to obtain the ideal conditions of the fluoride adsorption process with AA-ZnCl2, using a Central Compound Design for two factors (pH and adsorbent dosage) with response surface methodology. Kinetic and isothermal adsorption tests of fluoride were carried out for AACP and AA-ZnCl2, and the optimum adsorbent conditions proposed for adsorption of groundwater fluoride were obtained. In the preliminary tests AACP it presented fluoride removal efficiencies of 65.4 and 66% for synthetic solutions, and only 38.6% for groundwater. The adsorbent presented the best percentage of removal for both synthetic solutions (> 98%) and groundwater (55.4%). The analysis of the residual concentrations of fluoride, chloride, nitrate, sulfate and phosphate obtained for the synthetic solution of fluoride showed that these parameters meet the maximum permitted value stipulated by the Brazilian standard regulation of potability (Portaria de Consolidação nº 5/2017). The results of the procedure to obtain the ideal conditions of the fluoride adsorption process showed that the two variables, pH and adsorbent dosage, and their interactions on the adsorption capacity are significant at the level of significance adopted. The AA-ZnCl2 exhibited fluoride adsorption property in the pH range of 4 to 10, and the dosage defined as the ideal for the following experiments was 3 g L-1. The results of adsorption kinetics tests showed that AAZnCl2 presented an extremely fast and efficient adsorption. For an initial fluoride concentration of 5 mg L-1, a removal efficiency of 97.4% was achieved with only 5 minutes of contact time, and a fluoride residual of only 0.133 mg L-1 was obtained. The kinetic model of pseudo-second order was the one that most adequately described the kinetics of fluoride adsorption, presenting values of R2 ≥ 0.99. The results of the fluoride adsorption isotherms tests indicated that the Freundlich isotherm model fitted better to the experimental data than the Langmuir isotherm model. After the tests to obtain the optimum adsorbent conditions for adsorption of groundwater fluoride, it is concluded that the ideal dosage, sufficient to reduce the fluoride concentration to the limit established by Annex XX of “Portaria de Consolidação nº 5/2017”, was that of 5 g L- 1. The results showed that the adsorption with ZnCl2-modified activated alumina via ultrasonic assisted synthesis is efficient for the groundwater defluoration for human supply. |
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Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humanoAdsorptive processes applied to the defluoridation of underground water for human supplySíntese assistida por ultrassomDesfluoretaçãoÁguas subterrâneasCloreto de zincoÍons fluoretoCNPQ::ENGENHARIAS::ENGENHARIA CIVILFluoride (Fˉ) is an element that is commonly present in groundwater, and that in excessive concentrations may make it unfit for consumption. Contamination of groundwater by fluoride ions may occur through natural processes or due to anthropic activity, with the release of fluoride-containing industrial waste. Excessive intake of fluoride may, in the long run, cause so-called dental and skeletal fluorosis. In addition, ingestion of excess fluoride can also, in severe cases, lead to neurological damage, Alzheimer's disease and cancer. That is why it is fundamental to the de-watering of groundwater for human supply. Adsorption is a prominent technique among the available methodologies for water defluoride, being one of the most efficient in terms of cost, design and operation. In this sense, the main goal of the present study was the application of adsorption to groundwater defluoride for human supply in the State of Rio Grande do Sul. Preliminary tests were carried out for the removal of fluoride from synthetic solutions 5 mg L-1, in which several adsorbent, commercial and alternative. A process of ultrasonic assisted synthesis of an adsorbent based on activated alumina modified with ZnCl2 (AA-ZnCl2) has been proposed. In the characterization step, the adsorbents adsorbents adsorbents adsorbents commercial powder without chemical modification (AACP) and AAZnCl2 were obtained, and BET, EDS scanning electron microscopy, diffraction analysis of Xrays and FT-IR. A procedure was performed to obtain the ideal conditions of the fluoride adsorption process with AA-ZnCl2, using a Central Compound Design for two factors (pH and adsorbent dosage) with response surface methodology. Kinetic and isothermal adsorption tests of fluoride were carried out for AACP and AA-ZnCl2, and the optimum adsorbent conditions proposed for adsorption of groundwater fluoride were obtained. In the preliminary tests AACP it presented fluoride removal efficiencies of 65.4 and 66% for synthetic solutions, and only 38.6% for groundwater. The adsorbent presented the best percentage of removal for both synthetic solutions (> 98%) and groundwater (55.4%). The analysis of the residual concentrations of fluoride, chloride, nitrate, sulfate and phosphate obtained for the synthetic solution of fluoride showed that these parameters meet the maximum permitted value stipulated by the Brazilian standard regulation of potability (Portaria de Consolidação nº 5/2017). The results of the procedure to obtain the ideal conditions of the fluoride adsorption process showed that the two variables, pH and adsorbent dosage, and their interactions on the adsorption capacity are significant at the level of significance adopted. The AA-ZnCl2 exhibited fluoride adsorption property in the pH range of 4 to 10, and the dosage defined as the ideal for the following experiments was 3 g L-1. The results of adsorption kinetics tests showed that AAZnCl2 presented an extremely fast and efficient adsorption. For an initial fluoride concentration of 5 mg L-1, a removal efficiency of 97.4% was achieved with only 5 minutes of contact time, and a fluoride residual of only 0.133 mg L-1 was obtained. The kinetic model of pseudo-second order was the one that most adequately described the kinetics of fluoride adsorption, presenting values of R2 ≥ 0.99. The results of the fluoride adsorption isotherms tests indicated that the Freundlich isotherm model fitted better to the experimental data than the Langmuir isotherm model. After the tests to obtain the optimum adsorbent conditions for adsorption of groundwater fluoride, it is concluded that the ideal dosage, sufficient to reduce the fluoride concentration to the limit established by Annex XX of “Portaria de Consolidação nº 5/2017”, was that of 5 g L- 1. The results showed that the adsorption with ZnCl2-modified activated alumina via ultrasonic assisted synthesis is efficient for the groundwater defluoration for human supply.O fluoreto (Fˉ) é um elemento que está comumente presente na água subterrânea, e que em concentrações excessivas pode torna-la imprópria para consumo. A contaminação das águas subterrâneas por íons fluoreto pode ocorrer através de processos naturais ou devido à atividade antrópica, com o lançamento de despejos industriais contendo fluoreto. Uma ingestão excessiva de fluoreto pode, a longo prazo, causar a chamada fluorose dentária e esquelética. Além disso, a ingestão de fluoreto em excesso também pode, em casos graves, conduzir a lesões neurológicas, Mal de Alzheimer e câncer. Por isso é fundamental à desfluoretação da água subterrânea para abastecimento humano. A adsorção é uma técnica de destaque entre as metodologias disponíveis para desfluoretação da água, sendo uma das mais eficientes em termos de custo, concepção e operação. Nesse sentido, o presente estudo teve como objetivo principal a aplicação da adsorção para a desfluoretação de água subterrânea para abastecimento humano no Estado do Rio Grande do Sul. Para isso foram realizados ensaios preliminares para remoção de fluoreto de soluções sintéticas 5 mg L-1, nos quais foram utilizados diversos adsorventes, comerciais e alternativos. Foi proposto um processo de síntese assistida por ultrassom de um adsorvente à base de alumina ativada modificada com ZnCl2 (AA-ZnCl2). Na etapa de caracterização foram obtidos o ponto de carga zero dos adsorventes alumina ativada comercial em pó sem modificação química (AACP) e AA-ZnCl2, e foram utilizadas as técnicas de BET, microscopia eletrônica de varredura com EDS, análise de difração de raios-X e FT-IR. Foi realizado um procedimento para obtenção das melhores condições do processo de adsorção de fluoreto com a AA-ZnCl2, utilizando um Delineamento Composto Central para dois fatores (pH e massa de adsorvente), com metodologia de superfície de resposta. Foram realizados ensaios de cinética e isotermas adsorção de fluoreto para a AACP e a AA-ZnCl2, e obtidas as condições ideals do adsorvente proposto para adsorção de fluoreto da água subterrânea. Nos ensaios preliminares a AACP apresentou eficiências de remoção de fluoreto de 65,4 e 66% para soluções sintéticas, e de apenas 38,6% para a água subterrânea. Já a AA-ZnCl2 foi o adsorvente que apresentou o melhor percentual de remoção, tanto para soluções sintéticas (> 98%), quanto para a água subterrânea (55,4%). A análise das concentrações residuais de fluoreto, cloreto, nitrato, sulfato e fosfato obtidas para a solução sintética de fluoreto mostrou que esses parâmetros atendem ao valor máximo permitido estipulado pelo padrão brasileiro de potabilidade (Portaria de Consolidação n. 5/2017). Os resultados do procedimento para obtenção das melhores condições do processo de adsorção de fluoreto mostraram que as duas variáveis, pH e massa de adsorvente, e suas interações na capacidade de adsorção são significantes ao nível de significância adotado. A AA-ZnCl2 apresentou propriedade de adsorção de fluoreto na faixa de pH de 4 a 10, e a massa definida como a ideal para os experimentos seguintes foi de 3 g L−1. Os resultados dos ensaios de cinética de adsorção demonstraram que a AA-ZnCl2 apresentou uma adsorção extremamente rápida e eficiente. Para uma concentração inicial de fluoreto de 5 mg L-1, foi alcançada uma eficiência de remoção de 97,4% com apenas 5 minutos de tempo de contato, sendo obtido um residual de fluoreto de apenas 0,133 mg L-1. O modelo cinético de pseudo segunda-ordem foi o que descreveu mais adequadamente a cinética de adsorção de fluoreto, apresentando valores de R2 ≥ 0,99. Os resultados dos ensaios de isotermas de adsorção de fluoreto indicaram que o modelo de isoterma de Freundlich se ajustou melhor aos dados experimentais do que o modelo de isoterma de Langmuir. Após os ensaios para obtenção das condições ideals do adsorvente para adsorção de fluoreto da água subterrânea, conclui-se que a massa ideal, suficiente para reduzir a concentração de fluoreto ao limite estabelecido pelo Anexo XX da Portaria de Consolidação nº 5, foi a de 5 g L-1. Os resultados mostraram que a utilização da adsorção com alumina ativada modificada com ZnCl2 via síntese assistida por ultrassom é eficiente para a desfluoretação de água subterrânea para abastecimento humano.Universidade Federal de Santa MariaBrasilEngenharia CivilUFSMPrograma de Pós-Graduação em Engenharia CivilCentro de TecnologiaCarissimi, Elvishttp://lattes.cnpq.br/4642912749433316Féris, Liliana Amaralhttp://lattes.cnpq.br/5680941524872085Rodrigues, Cristiane Oliveirahttp://lattes.cnpq.br/9808965707951024Silva, William Leonardo dahttp://lattes.cnpq.br/0051813511298422Dotto, Guilherme Luizhttp://lattes.cnpq.br/5412544199323879Jahn, Sérgio Luizhttp://lattes.cnpq.br/7735147410610776Oliveira, Robson Alves de2019-11-06T14:27:17Z2019-11-06T14:27:17Z2019-04-26info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisapplication/pdfhttp://repositorio.ufsm.br/handle/1/18819porAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessreponame:Manancial - Repositório Digital da UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSM2023-09-04T12:18:05Zoai:repositorio.ufsm.br:1/18819Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufsm.br/ONGhttps://repositorio.ufsm.br/oai/requestatendimento.sib@ufsm.br||tedebc@gmail.comopendoar:2023-09-04T12:18:05Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM)false |
dc.title.none.fl_str_mv |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano Adsorptive processes applied to the defluoridation of underground water for human supply |
title |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano |
spellingShingle |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano Oliveira, Robson Alves de Síntese assistida por ultrassom Desfluoretação Águas subterrâneas Cloreto de zinco Íons fluoreto CNPQ::ENGENHARIAS::ENGENHARIA CIVIL |
title_short |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano |
title_full |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano |
title_fullStr |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano |
title_full_unstemmed |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano |
title_sort |
Processos adsortivos aplicados à desfluoretação de água subterrânea para abastecimento humano |
author |
Oliveira, Robson Alves de |
author_facet |
Oliveira, Robson Alves de |
author_role |
author |
dc.contributor.none.fl_str_mv |
Carissimi, Elvis http://lattes.cnpq.br/4642912749433316 Féris, Liliana Amaral http://lattes.cnpq.br/5680941524872085 Rodrigues, Cristiane Oliveira http://lattes.cnpq.br/9808965707951024 Silva, William Leonardo da http://lattes.cnpq.br/0051813511298422 Dotto, Guilherme Luiz http://lattes.cnpq.br/5412544199323879 Jahn, Sérgio Luiz http://lattes.cnpq.br/7735147410610776 |
dc.contributor.author.fl_str_mv |
Oliveira, Robson Alves de |
dc.subject.por.fl_str_mv |
Síntese assistida por ultrassom Desfluoretação Águas subterrâneas Cloreto de zinco Íons fluoreto CNPQ::ENGENHARIAS::ENGENHARIA CIVIL |
topic |
Síntese assistida por ultrassom Desfluoretação Águas subterrâneas Cloreto de zinco Íons fluoreto CNPQ::ENGENHARIAS::ENGENHARIA CIVIL |
description |
Fluoride (Fˉ) is an element that is commonly present in groundwater, and that in excessive concentrations may make it unfit for consumption. Contamination of groundwater by fluoride ions may occur through natural processes or due to anthropic activity, with the release of fluoride-containing industrial waste. Excessive intake of fluoride may, in the long run, cause so-called dental and skeletal fluorosis. In addition, ingestion of excess fluoride can also, in severe cases, lead to neurological damage, Alzheimer's disease and cancer. That is why it is fundamental to the de-watering of groundwater for human supply. Adsorption is a prominent technique among the available methodologies for water defluoride, being one of the most efficient in terms of cost, design and operation. In this sense, the main goal of the present study was the application of adsorption to groundwater defluoride for human supply in the State of Rio Grande do Sul. Preliminary tests were carried out for the removal of fluoride from synthetic solutions 5 mg L-1, in which several adsorbent, commercial and alternative. A process of ultrasonic assisted synthesis of an adsorbent based on activated alumina modified with ZnCl2 (AA-ZnCl2) has been proposed. In the characterization step, the adsorbents adsorbents adsorbents adsorbents commercial powder without chemical modification (AACP) and AAZnCl2 were obtained, and BET, EDS scanning electron microscopy, diffraction analysis of Xrays and FT-IR. A procedure was performed to obtain the ideal conditions of the fluoride adsorption process with AA-ZnCl2, using a Central Compound Design for two factors (pH and adsorbent dosage) with response surface methodology. Kinetic and isothermal adsorption tests of fluoride were carried out for AACP and AA-ZnCl2, and the optimum adsorbent conditions proposed for adsorption of groundwater fluoride were obtained. In the preliminary tests AACP it presented fluoride removal efficiencies of 65.4 and 66% for synthetic solutions, and only 38.6% for groundwater. The adsorbent presented the best percentage of removal for both synthetic solutions (> 98%) and groundwater (55.4%). The analysis of the residual concentrations of fluoride, chloride, nitrate, sulfate and phosphate obtained for the synthetic solution of fluoride showed that these parameters meet the maximum permitted value stipulated by the Brazilian standard regulation of potability (Portaria de Consolidação nº 5/2017). The results of the procedure to obtain the ideal conditions of the fluoride adsorption process showed that the two variables, pH and adsorbent dosage, and their interactions on the adsorption capacity are significant at the level of significance adopted. The AA-ZnCl2 exhibited fluoride adsorption property in the pH range of 4 to 10, and the dosage defined as the ideal for the following experiments was 3 g L-1. The results of adsorption kinetics tests showed that AAZnCl2 presented an extremely fast and efficient adsorption. For an initial fluoride concentration of 5 mg L-1, a removal efficiency of 97.4% was achieved with only 5 minutes of contact time, and a fluoride residual of only 0.133 mg L-1 was obtained. The kinetic model of pseudo-second order was the one that most adequately described the kinetics of fluoride adsorption, presenting values of R2 ≥ 0.99. The results of the fluoride adsorption isotherms tests indicated that the Freundlich isotherm model fitted better to the experimental data than the Langmuir isotherm model. After the tests to obtain the optimum adsorbent conditions for adsorption of groundwater fluoride, it is concluded that the ideal dosage, sufficient to reduce the fluoride concentration to the limit established by Annex XX of “Portaria de Consolidação nº 5/2017”, was that of 5 g L- 1. The results showed that the adsorption with ZnCl2-modified activated alumina via ultrasonic assisted synthesis is efficient for the groundwater defluoration for human supply. |
publishDate |
2019 |
dc.date.none.fl_str_mv |
2019-11-06T14:27:17Z 2019-11-06T14:27:17Z 2019-04-26 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://repositorio.ufsm.br/handle/1/18819 |
url |
http://repositorio.ufsm.br/handle/1/18819 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Engenharia Civil UFSM Programa de Pós-Graduação em Engenharia Civil Centro de Tecnologia |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Engenharia Civil UFSM Programa de Pós-Graduação em Engenharia Civil Centro de Tecnologia |
dc.source.none.fl_str_mv |
reponame:Manancial - Repositório Digital da UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Manancial - Repositório Digital da UFSM |
collection |
Manancial - Repositório Digital da UFSM |
repository.name.fl_str_mv |
Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
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1805922090422894592 |