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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Projektering av ett småhus med fördjupning i uppvärmningssystem

Dahlin, Tobias, Hedlin, My January 2012 (has links)
No description available.
102

Effects of various concentrations of soybean hull supplementation on performance, digestion and serum chemistry of weaned beef cattle fed ryegrass baleage

Tipton, Paige N 09 August 2019 (has links)
Graded concentrations of soybean hull pellets (SHP) fed to calves consuming annual ryegrass baleage was evaluated in two experiments. Experiment one evaluated performance and serum glucose of animals fed three treatments. Treatments were: 0.0% (TRT 0), 0.5% (TRT 0.5), 1.0% (TRT 1) body weight (BW) of SHP fed daily while calves had ad libitum access to baleage. Average daily gain and BW increased for calves receiving TRT 1 (P < 0.05). Experiment two evaluated passage rate of treatments using ytterbium chloride as a marker. Passage rate of diet decreased for TRT 1 compared to TRT 0 (10.9 h vs. 16.72 h TRT 1 and TRT 0 respectively, P < 0.05). Calves receiving TRT 0.5 had greater ADG than calves fed TRT 0 (0.54 kg/d and 0.30 kg/d respectively; P < 0.05). Diet passage rate decreased as supplement amount increased (P < 0.05). Serum glucose concentrations were not affected.
103

A NOVEL APPROACH FOR THE MANUFACTURING OF EXTENDED RELEASE PELLETS

MENENDEZ, CARLOS JUAN 02 July 2003 (has links)
No description available.
104

Panorama da poluição costeira por pellets de plástico em praias de SP (Brasil): uma contribuição aos estudos de geografia do litoral / Panorama of the coastal pollution through plastic pellets in beaches of SP (Brazil): a contribution to Coastal Geography studies

Falcão, Plínio Martins 17 September 2015 (has links)
O lixo marinho é um problema discutido desde a década de 1970, quando cientistas começaram a observar e quantificar materiais diversos nos mares e costas de alguns países, como por exemplo os plásticos. Nessa categoria se encontram os pellets de plástico, que constituem a matéria-prima de base para a produção da indústria mundial de insumos plásticos. Desde então o tema é tratado entre as formas de poluição marinha e costeira mais observadas. A pesquisa foi desenvolvida no litoral do Estado de São Paulo (Brasil), na qual se avaliou a presença de pellets e os mecanismos de sua distribuição, realizada em duas etapas: a primeira, em 55 praias de 15 municípios entre o Litoral Norte, a Baixada Santista e o Litoral Sul. A segunda, em 9 praias da Região Metropolitana da Baixada Santista. Pesquisa bibliográfica, documental, trabalhos de campo e de laboratório formaram as etapas da investigação, para a qual foram usados métodos de amostragem. Os resultados obtidos levaram à conclusão da maior concentração de pellets nas praias próximas às áreas consideradas pelo estudo como fontes emissoras do material no mar, como as zonas portuárias / industriais de São Sebastião, Santos e a de Paranaguá (Paraná). Ao longo das praias, foi constatado que os eventos extremos de ressacas / marés meteorológicas são os principais responsáveis pela distribuição dos pellets de plástico nas praias. A principal contribuição do trabalho foi a inclusão da temática da poluição costeira nos estudos de Geografia do Litoral, uma demanda desafiadora para a Geografia brasileira. / Marine debris is an issue discussed since the 1970s, when scientists began to observe and quantify different materials in the seas and coastlines of some countries, such as plastics. In this category are the plastic pellets, which are the basic raw material for the production of plastics industry worldwide inputs. Since then the issue is treated between forms of marine pollution and more coastal observed. The research was conducted in the São Paulo state coast (Brazil), in which it evaluated the presence of pellets and the mechanisms of its distribution, carried out in two stages: the first, on 55 beaches in 15 municipalities across the North Coast, the Baixada Santista and the South Coast. The second, on 9 beaches of Baixada Santista. Bibliographical research, documental, field work and laboratory formed the stages of the investigation, for which sampling methods were used. The results led to the conclusion of the higher concentration of pellets at the nearby beaches to areas considered by the study as sources emitting material at sea, such as port / industrial areas of São Sebastião, Santos and Paranaguá (Paraná). Along the beaches, it was found that extreme storm surge events are mainly responsible for the distribution of plastic pellets on beaches. The main contribution of this study was the inclusion of the issue of coastal pollution in the studies of Geography of the Coastline, a challenging demand for Brazilian Geography.
105

Obtenção de comprimidos contendo grânulos deformantes e grânulos revestidos gastro-resistentes / Obtaintion of tablets containing soft and gastroresistant coated pellets

Kratz, Cristiane de Pellegrini January 2002 (has links)
Sistemas monolíticos particulados contendo os constituintes ativos veiculados na forma de grânulos revestidos - pellets - têm recebido crescente atenção nos últimos anos, em função da otimização na biodisponibilidade e segurança na liberação do fármaco. A utilização destas unidades, como componentes de comprimidos traz, como principal vantagem, a divisibilidade da forma sem a perda do perfil biofarmacêutico desejado para o fármaco. Para sua produção, é indispensável a manutenção da integridade do revestimento daquelas unidades. Uma estratégia para o alcance deste objetivo envolve a utilização de grânulos inertes deformantes, comprimidos em conjunto com os grânulos revestidos, que atuam como um sistema de amortecimento das forças de compressão. Neste trabalho investigou-se a produção de grânulos deformantes através de dois métodos de granulação por via úmida, avaliando a influência de adjuvantes sobre as características dos produtos obtidos. Empregando a técnica de extrusão/esferonização obtiveram-se grânulos com propriedades de fluxo, empacotamento e resistência mecânica aceitáveis. O efeito dos adjuvantes sobre as etapas tecnológicas foi estudado por meio de um planejamento fatorial. Testaram-se duas variedades de celulose microcristalina, os desintegrantes croscarmelose sódica e crospovidona e soluções aglutinantes aquosas e hidroetanólicas de povidona. Para o desenvolvimento dos comprimidos utilizaram-se, como modelo, grânulos revestidos gastro-resistentes contendo omeprazol. A influência da composição dos grânulos deformantes sobre a liodisponibilidade do fármaco dos comprimidos foi avaliada através de análise fatorial 23. Os grânulos deformantes protegeram o revestimento polimérico dos pellets com diferentes intensidades. / Monolythic particulate systems containing the active constituents as coated pellets became great interest due to the improvement of safety and bioavailability. The use of such units as components of tablets shows as main advantages the divisibility of the pharmaceutical dosage form without loosing the desired biopharmaceutical profile of the drug. Consequently for the tablet production, the integrity of the polymeric film must be attained. A strategic option involves the utilization of inert soft pellets, which could be compressed together with the film coated pellets, absorbing the compaction forces. In this work the production of soft pellets was investigated using two wet granulation methods and evaluating the influence of formulation adjuvants on the pellets properties. The extrusion/spheronization technique yielded pellets with acceptable flow, packing and mechanical characteristics. The influence of the adjuvants on the technological steps was carried out through a statistical designed experiment. Microcrystalline cellulose from two producers, the disintegrants sodium croscarmellose and crospovidone, and aqueous and hydroethanolic dispersions of povidone, as binder, were tested. For the tablets development omeprazol gastroresistant film coated pellets were used as model. Aiming at the study of the influence of the soft pellets composition on drug lyoavailability was performed a 23 factorial experiment. The soft pellets protected at different intensities the polymeric coating of the gastroresistant pellets.
106

Estudo da distribuição de metais em plásticos no litoral de São Paulo: avaliação da poluição por meio de análise de pellets / Study of the distribution of metals in plastics at São Paulo coast: an avaliation of pollution with analysis of plastic pellets

Vedolin, Marcela Corrêa 17 March 2014 (has links)
A matéria prima das indústrias transformadoras de utensílios plásticos são os pellets de plástico, que recebem quantidades significativas de aditivos os quais possuem metais pesados e elementos tóxicos. Devido à perda desses pellets durante os processos de produção e transporte, tais contaminantes são liberados no ambiente. Este estudo investiga as interações entre os metais dissolvidos em pellets coletados em diferentes praias do litoral de São Paulo. Especificamente, o estudo comparou a realização do método em grânulos virgens, ou seja, aqueles obtidos a partir de uma fábrica de moldagem com os recolhidos das praias. Foram quantificados os elementos: Al, Cr, Cu, Fe, Mn, Sn, Ti e Zn empregando a técnica de espectrometria de emissão atômica com plasma indutivamente acoplado (ICP-OES). Os polímeros foram solubilizados via digestão ácida (EPA3050B). As concentrações dos metais exibiram um elevado grau de variabilidade, sendo Al e Fe os elementos de maiores concentrações 58,63 mg kg-1, praia de Tabatinga e 391,56 mg kg-1, praia de Itaguaré, respectivamente. Diferenças de afinidades entre os metais para os pellets coletados no ambiente e aqueles obtidos diretamente a partir de uma processadora de plásticos (virgem) também foram identificados. A adsorção de metais em pellets coletados é maior em relação aos pellets virgens, isso ocorre devido ao desenvolvimento de sítios de adsorção na superfície para realização de foto-oxidação, incrustação e deposição de sedimentos finos e/ou partículas durante a exposição a condições ambientais. Este estudo demonstrou que pellets de plástico têm o potencial acumular e transportar metais no ambiente marinho, mesmo em pequena quantidade. Eles podem ser considerados como um vetor para o transporte de metais no meio ambiente, e podem ter o potencial de acumular metais em organismos após a ingestão. / The raw material of plastic industries is plastic pellets, which receive significant amounts of additives which contain heavy metals and toxic elements. Due to the loss of these pellets during the processes of production and transportation, such contaminants are released into the environment. This study investigates the interactions between metals dissolved in pellets collected in different beaches of the coast of São Paulo state. Specifically, the study compared the performance of the method in virgin granules, ie, those obtained from a molding factory with those collected from the beaches. The following elements quantified: Al , Cr , Cu , Fe , Mn , Sn , Ti and Zn in samples of virgin pellets supplied by Braskem, manufacturer of resins, employing the technique of Inductively coupled plasma atomic emission spectroscopy ( ICP - OES .) The polymers were solubilized via acid digestion (EPA3050B). The metal concentrations exhibited a high degree of variability being Al and Fe elements with higher concentrations: 58.63 mg kg-1 at Tabatinga beach and Fe 391.56 mg kg-1, at Itaguaré beach. Affinity differences between metals for pellets collected in the environment and those obtained directly from a processor of plastics (virgin) were also identified. The maximum adsorption for virgin pellets ranged between 14.09 mg kg-1 (polyethylene, used as control) to 58.63 mg kg-1 for Al. However, for the other elements except Fe, the concentrations were below the limit of quantification. The metal adsorption on pellets collected is greater compared to virgin pellets. This is due to the development of viable local surface for performing photo-oxidation, scaling and deposition of fine sediments and/or particles during exposure to environmental conditions. This study demonstrated for the first time, that the plastic pellets have the potential to accumulate metals and transporting the marine environment, even in small quantities. They can be considered as a vector for the transport of metals in the environment and may have the potential to accumulate metal to organisms bodies after ingestion.
107

Desenvolvimento de formas farmacêuticas sólidas contendo extratos padronizados em psoraleno e bergapteno a partir de Brosimum gaudichaudii

Rodrigues, Mariana Cristina de Morais 21 March 2016 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-08-09T19:14:53Z No. of bitstreams: 2 Dissertação - Mariana Cristina de Morais Rodrigues - 2016.pdf: 1662967 bytes, checksum: 21eacb29fa5e6184be947945ff9816a4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-10T11:28:58Z (GMT) No. of bitstreams: 2 Dissertação - Mariana Cristina de Morais Rodrigues - 2016.pdf: 1662967 bytes, checksum: 21eacb29fa5e6184be947945ff9816a4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-10T11:28:58Z (GMT). No. of bitstreams: 2 Dissertação - Mariana Cristina de Morais Rodrigues - 2016.pdf: 1662967 bytes, checksum: 21eacb29fa5e6184be947945ff9816a4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-21 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Brosimum gaudichaudii Trécul. from the Moraceae family is traditionally used as a therapeutic resource to treat leukoderma. The roots are the plant’s part that contain the highest concentration of photosensitizing substances, important against leukoderma, among them psoralen and bergapten that belong to the secondary metabolite class named linear furanocoumarins. By definition, phytotherapic is the product obtained exclusively from active vegetal raw material with prophylactic, curative or palliative purpose. They characteristically do not include isolated or highly purified substances in their composition from any source, or are associated with other extracts. One of the main challenges in producing phytotherapic medicine is the complex composition of the medicinal plant that depends on climatic and geographic factors, and cultivation, drying and storage conditions. The objective of this work was to obtain solid pharmaceutical forms containing extract standardized in psoralen and bergapten of B. gaudichaudii, as well as the analyses of these pharmaceutical forms following all the parameters stated by the Normative instruction no 04 of 2014. Chapter 1 is about the vegetal drug characterization and posterior production and standardization of the liquid extract, the analytical method was co-validated by High Efficiency Liquid Chromatography (CLAE) to determine the markers levels in the liquid extract, according to ANVISA norms. The method presented to be selective, linear, precise and exact. The liquid extract was standardized in total furanocoumarins expressed in psoralen and bergapten, and the level was 0.20% (m/v) (20.81 μg/mL of psoralen and bergapten). Chapter 2 describes the development of coated pellets containing the liquid standardized extract, having an average diameter of 0.75±0.08 mm and sphericity of 0.98±0.09. The acquired pellets were encapsulated in hard gelatinous capsules (500 mg of pellets per capsule), the average level of total furanocoumarins per capsule was 641.41 μg. Tablets containing the coated pellets were produced, and it was possible to keep the pellets whole, even after the compression force of 0.5 ton was applied on them. The tablets were tested according to the analyses recommended by the Brazilian Pharmacopeia and presented a total furanocoumarin level of 587.6 μg per tablet. The analytical methodology was co-validated for the quantification of psoralen and bergapten in the coated pellets and the tablets containing them. Chapter 3 describes the obtainment and standardization of the soft extract from B.gaudichaudii and the development of tablets containing the soft extract. The soft extract was characterized according the pharmacopeia tests, and there were 82.02% (m/m) of dry residue, and the total furanocoumarin levels expressed in psoralen and bergapten was 2.93% (m/v) (58.8 μg/g of psoralen and bergapten). Three different formulations of tablets containing soft standardized extract were acquired by humid rout previous granulation. In each formulation the diluents, microcrystalline cellulose (MCC) and starch proportion were variated. The compression was done in a hydraulic press and the process was controlled to establish the compression conditions. The analytical methodology was co-validated to quantify the total furanocoumarins in the tablets and the level were 16,800 μg per tablet. / Brosimum gaudichaudii Trécul. pertencente a família Moraceae é tradicionalmente utilizada como recurso terapêutico para o tratamento de leucodermias .A raiz desta planta é a parte que contém maior concentração de substâncias fotossensibilizantes importantes contra leucodermias, dentre elas o psoraleno e o bergapteno que pertencem à classe de metabólitos secundários denominados furanocumarinas lineares. Por definição, fitoterápico é o produto obtido exclusivamente de matéria prima ativa vegetal com propósito profilático, curativo ou paliativo. Caracterizam-se por não incluir na sua composição substâncias ativas isoladas ou altamente purificadas, de qualquer origem, nem as associações dessas com outros extratos. Um dos principais desafios na produção de um medicamento fitoterápico é a complexidade da composição da planta medicinal, que depende de fatores climátios, geográficos, condições de cultivo, secagem e armazenamento. O presente trabalho teve como objetivo a obtenção de formas farmacêuticas sólidas contendo o extrato padronizado em psoraleno e bergapteno de B. gaudichaudiii, bem como a análise destas formas farmacêuticas seguindo todos os parâmetros exigidos pela Instrução normativa n° 04 de 2014. O capítulo 1 trata da caracterização da droga vegetal e posteriormente a obtenção e padronização do extrato líquido, covalidou-se o método analítico por Cromatografia a Líquido de Alta Eficiência (CLAE) para determinação dos teores dos marcadores no extrato líquido, segundo as normas da ANVISA. O método mostrou-se seletivo, linear, preciso e exato. O extrato líquido foi padronizado em furanocumarinas totais expressas em psoraleno e bergapteno, e obteve-se o teor de 0,20% (m/v) (20,81 μg/mL de psoraleno e bergapteno). O capítulo 2 descreve o desenvolvimento de pellets revestidos contendo o extrato líquido padronizado obtido, tendo um diâmetro médio 0,75+0,08 mm e esfericidade 0,98+0,09. Encapsulou-se os pellets obtidos em cápsulas gelatinosas duras (500mg de pellets por cápsula), o teor médio de furanocumarinas totais por cápsula foi 641,41μg. Obteve-se comprimidos contendo pellets revestidos e foi possível manter os pellets íntegros mesmo após aplicada à força de compressão de 0,5 ton nos mesmos. Os comprimidos foram analisados segundo os testes preconizados pela Farmacopeia Brasileira e apresentaram um teor de furanocumarinas totais de 587,6μg por comprimido. A metodologia analítica foi covalidada para quantificação do psoraleno e bergapteno tanto nos pellets revestidos como nos comprimidos contendo pellets. O capítulo 3 descreve a obtenção e padronização do extrato mole de B.gaudichaudii e o desenvolvimento de comprimidos contendo o extrato mole obtido. O extrato mole foi caracterizado segundo os testes farmacopeicos e obteve 82,02% (m/m) de teor de sólidos, e o teor de furanocumarinas totais expressas em psoraleno e bergapteno que foi 2,93% (m/v) (58,8 μg/g de psoraleno e bergapteno). Obtiveram-se três diferentes formulações de comprimidos por previa granulação por via úmida, contendo o extrato mole padronizado. Em cada formulação variou-se a proporção dos diluentes celulose microcristalina (MCC) e amido. A compressão foi feita por meio de uma prensa hidráulica e efetuou-se o controle do processo para o estabelecimento das condições de compressão. A metodologia analítica foi covalidada para quantificação de furanocumarinas totais nos comprimidos obtidos, e a concentração de furanocumarinas totais para cada comprimido foi 16800 μg por comprimido.
108

Some aspects on the reduction of olivine pellets in laboratory scale and in an experimental blast furnace

Sterneland, Jerker January 2002 (has links)
The reduction behaviour of the olivine iron ore pellet MPBOwas studied in laboratory scale at KTH as well as in the LKABexperimental blast furnace. Initially, a newreduction-under-load, or so-called reduction/softening/melting,test equipment was developed. Experiments using differentreducing conditions, corresponding to different radialpositions of the blast furnace, were conducted. The experimentsincluded different temperature profiles, reducing atmospheresand mechanical loads applied on the sample bed to simulate thevarying conditions in the blast furnace process. The progressof reduction was investigated, as well as the processes ofsintering and contraction during reduction. A model of thecarburisation (pick-up of carbon by the reduced iron) andmelt-down process during rapid contraction was presented. Laboratory testing of MPBO pellets was compared with resultsfrom the LKAB experimental blast furnace. The reduction of ironore pellets in the experimental blast furnace was surveyed by adissection of the furnace after quenching. The high temperaturephenomena occurring when reducing the MPBO pellet, with limitedsoftening and a short temperature range of the melting process,resulting in a thin cohesive zone, were found to be the same inlaboratorytests and in the experimental blast furnace. Thereduction down through the burden of the experimental blastfurnace was similar, but not identical to the results of theRUL experiments. The differences were found to be due todifferent reducing conditions. Therefore, it was concluded thata simulation of the reduction occurring in the blast furnacecan be performed in laboratory scale, provided the experimentalconditions are correctly chosen. Finally, a modification to further improve the properties ofthe MPBO pellets was examined. With the aim to improve theblast furnace process, coating of blast furnace pellets wasinvestigated in laboratory scale, as well as in the LKABexperimental blast furnace. Olivine, dolomite and quartzitewere used as coating agents. In laboratory scale the stickingprevention action of the different coating materials wasverified, in established test methods as well as in new testmethods, modified for blast furnace conditions. Testing of thecoated pellets in the experimental blast furnace revealedseveral advantages; significantly reduced blast furnace fluedust generation, improved gas utilisation and a smoother blastfurnace operation with a potential for a lowered fuel rate. <b>Keywords:</b>Olivine, pellets, pellet testing,reduction/softening/melting, MPBO, blast furnace, reduction,quenching, dissection, coating, sticking, coated pellets.
109

Some aspects on the reduction of olivine pellets in laboratory scale and in an experimental blast furnace

Sterneland, Jerker January 2002 (has links)
<p>The reduction behaviour of the olivine iron ore pellet MPBOwas studied in laboratory scale at KTH as well as in the LKABexperimental blast furnace. Initially, a newreduction-under-load, or so-called reduction/softening/melting,test equipment was developed. Experiments using differentreducing conditions, corresponding to different radialpositions of the blast furnace, were conducted. The experimentsincluded different temperature profiles, reducing atmospheresand mechanical loads applied on the sample bed to simulate thevarying conditions in the blast furnace process. The progressof reduction was investigated, as well as the processes ofsintering and contraction during reduction. A model of thecarburisation (pick-up of carbon by the reduced iron) andmelt-down process during rapid contraction was presented.</p><p>Laboratory testing of MPBO pellets was compared with resultsfrom the LKAB experimental blast furnace. The reduction of ironore pellets in the experimental blast furnace was surveyed by adissection of the furnace after quenching. The high temperaturephenomena occurring when reducing the MPBO pellet, with limitedsoftening and a short temperature range of the melting process,resulting in a thin cohesive zone, were found to be the same inlaboratorytests and in the experimental blast furnace. Thereduction down through the burden of the experimental blastfurnace was similar, but not identical to the results of theRUL experiments. The differences were found to be due todifferent reducing conditions. Therefore, it was concluded thata simulation of the reduction occurring in the blast furnacecan be performed in laboratory scale, provided the experimentalconditions are correctly chosen.</p><p>Finally, a modification to further improve the properties ofthe MPBO pellets was examined. With the aim to improve theblast furnace process, coating of blast furnace pellets wasinvestigated in laboratory scale, as well as in the LKABexperimental blast furnace. Olivine, dolomite and quartzitewere used as coating agents. In laboratory scale the stickingprevention action of the different coating materials wasverified, in established test methods as well as in new testmethods, modified for blast furnace conditions. Testing of thecoated pellets in the experimental blast furnace revealedseveral advantages; significantly reduced blast furnace fluedust generation, improved gas utilisation and a smoother blastfurnace operation with a potential for a lowered fuel rate.</p><p><b>Keywords:</b>Olivine, pellets, pellet testing,reduction/softening/melting, MPBO, blast furnace, reduction,quenching, dissection, coating, sticking, coated pellets.</p>
110

Adsor??o de Pb(II) utilizando adsorvente composto por montmorilonita e dolomita

Pinto, Elida Natasche de Medeiros Gurgel 16 April 2011 (has links)
Made available in DSpace on 2014-12-17T14:07:00Z (GMT). No. of bitstreams: 1 ElidaNMGP_DISSERT.pdf: 266264 bytes, checksum: 55a4fffa9b1f2a291d7fc9168a9d61cd (MD5) Previous issue date: 2011-04-16 / The destructive impact of improper disposal of heavy metals in the environment increases as a direct result of population explosion, urbanization and industrial expansion and technological developments. Argil are potential materials for adsorption of inorganic and the pelletization of it is required for use in adsorptive columns of fixed bed. The low cost and the possibility of regeneration makes these materials attractive for use in the purification process, capable of removing inorganic compounds in contaminated aquatic environments. In this work was made pellets of a mixture of dolomite and montmorillonite by wet agglomeration, in different percentages. The removal of Pb (II) was investigated through experimental studies, and was modeled by kinetic models and isotherms of adsorption. The materials were characterized using the techniques of XRD, TG / DTA, FT-IR, and surface area by BET method. The results showed the adsorption efficiency of the contaminant by the composite material studied in synthetic solution. The study found that the adsorption follows the Langmuir model, and the kinetics of adsorption follows the model of pseudosecond order / O impacto destrutivo da disposi??o inadequada de metais pesados no meio ambiente aumenta como resultado direto da explos?o populacional, urbaniza??o e expans?o industrial e tecnol?gica. Argilas s?o potenciais materiais para adsor??o de compostos inorg?nicos e a pelletiza??o destes ? necess?ria para utiliza??o em colunas adsortivas de leito fixo. O baixo custo e a possibilidade de regenera??o fazem desses materiais um atrativo para a utiliza??o em processos de purifica??o, capazes de remover compostos inorg?nicos em ambientes aqu?ticos contaminados. Neste trabalho foram preparados pellets com mistura de montmorilonita e dolomita atrav?s da aglomera??o por via ?mida, em diferentes raz?es. A remo??o de Pb(II) foi investigada, atrav?s de estudos experimentais, e foi modelada segundo modelos de cin?tica e isotermas de adsor??o. Os materiais foram caracterizados atrav?s das t?cnicas de DRX, TG/DTA, FT-IR, e ?rea superficial pelo m?todo BET. Os resultados mostraram a efici?ncia adsortiva do contaminante estudado pelo material composto em solu??o sint?tica e foi verificado que a adsor??o segue o modelo de Langmuir e a cin?tica de adsor??o segue o modelo de pseudo-segunda ordem

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