O Brasil ocupa posição de destaque no mercado de açúcar a granel e consumo elevado deste ingrediente na forma líquida, em especial pelas indústrias de bebidas e alimentos. O açúcar líquido apresenta vantagens em relação ao açúcar a granel como facilidade do manuseio e dosagem, espaço reduzido para a armazenagem, redução das perdas, custos e mão-de-obra, melhora na sanitização e grande variação possível nas proporções de diferentes misturas de açúcares. O açúcar Uquido invertido é uma solução de sacarose, glicose e frutose em água e recebe esse nome porque durante a sua produção há a inversão do poder óptico de rotação da solução. No processo produtivo do açúcar invertido existem alguns pontos que podem gerar a contaminação por microrganismos, dessa forma torna-se importante o desenvolvimento de técnicas que propiciem a sanitização eficiente desta matéria-prima. Este trabalho estudou duas técnicas alternativas de controle microbiano: a radiação gama com fonte de cobalto-60 e a radiação com feixe de elétrons. O estudo foi conduzido nas doses de 5, 10, 20, 30 e 50 kGy. O teor de sacarose apresentou decréscimo com a radiação indicando que ocorreu a quebra da ligação glicosídica com a formação de glicose e fioitose, gerando o aumento do teor de sólidos solúveis. Ocorreu a formação de compostos ácidos, confirmado pela redução de pH, que foi proporcional ao aumento da dose de radiação. As maiores doses provocaram alterações na cor do xarope pela formação de polímeros com cadeia molecular longa. A viscosidade nas amostras irradiadas com radiação gama aumentou em relação ao controle, indicando a prevalência de polimerização das moléculas, enquanto que na radiação com feixe de elétrons a polimerização foi observada somente na amostra que recebeu a dose de 50 kGy. Na análise sensorial, os julgadores apontaram diferença significativa (5%) no sabor entre o controle e as amostras irradiadas com 5 kGy, nas duas técnicas de processamento. Não foi possível identificar o efeito da radiação gama no controle de bolores e leveduras. / Brazil occupies position of prominence in the sugar market and high consumption of this ingredient in the liquid form, in special for the beverages and food industries. The liquid sugar presents advantages in relation to the bulk granulated system such as easiness of the handling and dosage, reduced space for the storage, reduction of the losses, costs and hand of workmanship, improvement of the sanitizing and great possible variation in the ratios of different mixtures of sugars. The inverted liquid sugar is a solution of sucrose, glucose and fructose in water. This ingredient receives this name because during its production it has an inversion of the optic power of rotation of the solution. In the productive process of the inverted sugar some points occur that can generate contamination by microorganisms, so its become important the development of techniques that propitiate the efficient sanitizing of this raw material. This work aims at to consider two alternative techniques of microbiologic control: gamma radiation with source of cobalto-60 and radiation with electron beam. The study was lead in the doses of 5, 10, 20, 30 and 50 kGy. Concentration of sucrose presented in syrup decreased with the radiation indicating the scission of glicosidic linkage in addition with the glucose and fiaictose formation, generating the increase in solids soluble. The acid compounds formation occurred, confirmed by the reduction of pH, that it was proportional with the increase of the radiation dose. The biggest doses had provoked change of color in the syrup by the long molecular chain polymers formation. Viscosity in the samples processed by gamma radiation increased in relation to the control, indicating the prevalence of polymerization of molecules, whereas in the radiation with electron beam the polymerization was only observed in the sample that received the dose of 50 kGy, In the sensorial analysis, the judges had pointed significant difference (5%) in the flavor among control and the samples radiated with 5 kGy in the two techniques of processing. The alterations provoked for the irradiation had not been enough to provide significant changes in the inverted sugar, even in the highest dose of 50 kGy. It was not possible to identify the effect of gamma radiation in the control of molds and yeasts.

<p>Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzo-furans (PCDFs) belong to the most toxic compounds known to science and they are defined as Persistent Organic Pollutants (POPs) under the Stock-holm Convention. The general human exposure to PCDD/Fs is primarily through dietary intake. The importance of contaminated sites as secondary PCDD/F sources (i.e. sources that once received its contamination from a primary source) are getting increased attention. To be able to assess the risks for human exposure at PCDD/F contaminated sites, the environmen-tal distribution of PCDD/Fs and the potential mobilization between dif-ferent environmental media (e.g. food chain transfer) must be known. The primary aim of the work presented in this thesis was to investigate human exposure pathways associated with PCDD/F contaminated sites by combining field measurements and modeling. Site specific field measurements were made at a PCDD/F contaminated site in Sweden and multimedia modeling scenarios were evaluated against site specific data and national reference data.</p><p>The results show that the congener distributions in exposure media affected by contaminated soil may differ significantly from the distribu-tions found in media from reference locations. Higher chlorinated PCDD/Fs may be transferred into food chains where they contribute to a large fraction of the toxic equivalent concentration (TEQ). Ingestion of locally produced animal food may be an important exposure pathway al-ready at low or moderate PCDD/F soil concentrations. However, the con-gener composition of the source is critical for the exposure. The signifi-cance of the individual exposure routes varies depending on e.g. the spatial distribution and magnitude of the soil contamination, the pro-perties of the exposure media and the human behavior. Multimedia mo-deling can be used in risk assessments as long as model algorithms and model parameters are representative for the superhydrophobic properties of PCDD/Fs. However, selection of physical-chemical PCDD/F properties is a challenge due to large variation in reported values. For some proper-ties, data is scattered or completely lacking</p>

Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzo-furans (PCDFs) belong to the most toxic compounds known to science and they are defined as Persistent Organic Pollutants (POPs) under the Stock-holm Convention. The general human exposure to PCDD/Fs is primarily through dietary intake. The importance of contaminated sites as secondary PCDD/F sources (i.e. sources that once received its contamination from a primary source) are getting increased attention. To be able to assess the risks for human exposure at PCDD/F contaminated sites, the environmen-tal distribution of PCDD/Fs and the potential mobilization between dif-ferent environmental media (e.g. food chain transfer) must be known. The primary aim of the work presented in this thesis was to investigate human exposure pathways associated with PCDD/F contaminated sites by combining field measurements and modeling. Site specific field measurements were made at a PCDD/F contaminated site in Sweden and multimedia modeling scenarios were evaluated against site specific data and national reference data. The results show that the congener distributions in exposure media affected by contaminated soil may differ significantly from the distribu-tions found in media from reference locations. Higher chlorinated PCDD/Fs may be transferred into food chains where they contribute to a large fraction of the toxic equivalent concentration (TEQ). Ingestion of locally produced animal food may be an important exposure pathway al-ready at low or moderate PCDD/F soil concentrations. However, the con-gener composition of the source is critical for the exposure. The signifi-cance of the individual exposure routes varies depending on e.g. the spatial distribution and magnitude of the soil contamination, the pro-perties of the exposure media and the human behavior. Multimedia mo-deling can be used in risk assessments as long as model algorithms and model parameters are representative for the superhydrophobic properties of PCDD/Fs. However, selection of physical-chemical PCDD/F properties is a challenge due to large variation in reported values. For some proper-ties, data is scattered or completely lacking

From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / Sewage effluent for irrigation is well established. This study determines the capacity of selective turfgrass-soil systems to purify municipal sewage effluent and to measure the degree of utilization of nitrogen in the effluent by turfgrass. Chlorinated secondarily treated sewage effluent from the city of Tucson was applied to turfgrass grown on sandy loam, silt and loam, under three levels of irrigation under laboratory conditions of duplicate pots. Each pot had 2 suction probes to estimate soil moisture tensions and to allow soil water sampling. The study operated from September to March, 1972, for 30 weeks. Purification efficiency, nitrogen utilization and percent recharge were calculated. Turfgrass can be irrigated with sewage effluent at common rates without hazard of nitrogen pollution to groundwater. Purification efficiency exceeded 90 percent for all irrigation levels on sandy loam and silt. Nitrogen utilization was greater over sandy loam. Turfgrass-soil systems can utilize nitrogen and purify waste water.

From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / Water shortages in the Western United States have intensified the search for new sources. Wastewater reuse is being increasingly called upon to augment existing supplies. One potential impediment to the continued expansion of wastewater reuse efforts is the accumulation of toxic heavy metals and other salts in the recycled water. Conventional and advanced wastewater treatment effect the removal of a portion of the heavy metals added during use. Removal is by chemical precipitation and adsorption and disposed of with the sludges. Potential uses of treated wastewater effluents include irrigation and groundwater recharge. Care must be taken to prevent contamination of groundwater, especially since existing wells have been reported to have concentrations of heavy metals in excess of drinking water standards. Percolation of wastewaters through soils (especially fine soils) results in a reduction in heavy metal concentrations. It is postulated that removal of these metals is by a combination of chemical precipitation with filtration of the precipitates, and adsorption on soil particles (thus the effectiveness of fine soils). Long term saturation of the soils with heavy metals may result in a "breakthrough" contamination of the groundwater. A predictive model of heavy metal-wastewater-soil interactions is proposed to aid in the design and regulation of wastewater reuse systems to eliminate or minimize this problem.

Effective agricultural planning and environmental monitoring requires basic soil information. However, analyzing soil properties by conventional methods is often expensive and time consuming. In addition, these analyses result in chemical residues, which may be environmentally hazardous. In recent decades near-infrared diffuse reflectance spectroscopy (400-2500 nm) has been shown to be a viable alternative for rapidly analyzing soil properties. Information needs to be mathematically extracted from the spectra in order to correlate them with soil properties, and multivariate statistics are often used to calibrate soil prediction models.However, soils evaluated by the mid-IR region (4000 to 400 cm-1) warrants new studies. The primary aim of this study was to investigate the feasibility to use soil spectral data and chemometrics methods to predict soil properties, in order to reduce the number of conventional soil analyses. The understanding of the relationships between spectral characteristics and the physic-chemical properties of soils were evaluated in three different studies with soils of: (i) spectral library (Chapter 1), (ii) amazonian region (Chapter 2), (iii) soils contaminated with heavy metals and tannery sludge (Chapter 3).It was possible to identify regions of the vis-NIR and mid-IR spectra that showed absorption features due to water, iron oxides, and clay minerals. In Chapter 1 the predicted models for clay and soil organic matter showed high accuracy. It reflects the influence of the direct spectral responses of these properties in the NIR. The division of the large library into smaller subsets based on variation in the spectra characteristics was the best alternative to quantify soil attributes in tropical soils by Partial Least Square regressions. Another alternative would be to use Boosted regression trees for the whole library. In Chapter 2, the mid-IR predicted models outperformed the vis-NIR. Comparison of the interpolation results revealed that the predictions of the PLS regression (mid-IR and vis-NIR) adequately reproduced the spatial pattern of the properties evaluated, especially soil organic carbon and cation exchange capacity and, had the ability to predict the soil properties of unknown samples from a different geographical location. In Chapter 3, the metals adsorption to soil constituents caused expressive changes in soil spectral curves, showing spectral differentiation between highly contaminated soil and soils that are relatively contaminant-free. The results indicate that the Cr pseudo-total content can be predicted by spectroscopy reflectance with both sensors data. Fe and Mn also can be predicted accuratley by vis-NIR. The vis-NIR models outperformed the mid-IR. Besides these results, the vis-NIR instrument has less complicated sample and can be used directly in the field using portable spectrorradiometers. / Para o planejamento agrícola e o monitoramento ambiental são necessárias informações sobre os solos. As análises de solos realizadas através de métodos convencionais em laboratório são normalmente caras e demoradas. Além disso, geram resíduos químicos que caso não sejam dispostos e/ou tratados adequadamente, podem contaminar o ambiente. Nas últimas décadas a espectroscopia de reflectância difusa na região do visível e infravermelho próximo (vis-NIR, 400-2500 nm) do espectroeletromagnético tem se mostrado uma alternativa viável para analisar atributos de solo de maneira rápida. Para tanto, a informação espectral é matematicamente extraída do espectro e métodos multivariados são usados afim de correlacioná-la com as propriedades do solo. Entretanto, ainda são poucos estudos de solos em que a espectroscopia de reflectância na região do infravermelho médio (mid-IR, 4000-400 cm-1) foi usada. Objetivaram-se com este trabalho investigar a viabilidade da utilização de dados espectrais vis-NIR e mid-IR de solos e métodos quimiométricos para predizer as propriedades dos mesmos, a fim de reduzir o número de análises convencionais de terra. As relações existentes entre características espectrais e propriedades físico-químicas de solos tropicais foram avaliadas em três estudos distintos com solos (i) de uma biblioteca espectral (Capítulo 1), (ii) da região amazônica (Capítulo 2) e, (iii) contaminados com metais pesados e lodo de curtume (Capítulo 3). Foi possível identificar faixas espectrais nas regiões do vis-NIR e mid-IR relacionadas às feições de absorção características da água, óxidos de ferro e minerais de argila. No capítulo 1 os modelos de predição vis-NIR de argila e matéria orgânica do solo apresentaram elevada acurácia. Isto reflete a influência direta destas propriedades do solo na sua resposta espectral. A divisão da biblioteca espectral em subgrupos menores baseada nas características espectrais foi eficiente na quantificação de atributos de solos tropicais. Outra alternativa foi usar o método de regressão de árvores para o conjunto total de dados. No capítulo 2, os modelos de predição mid-IR foram mais precisos que os vis-NIR. Os modelos de carbono orgânico do solo e capacidade de troca catiônica obtidos pela regressão pelo método dos mínimos quadrados parciais permitiram a reprodução do padrão espacial destas propriedades na área estudada (r > 0.81); e puderam ser aplicados em uma área geográfica diferente, em amostras de solos desconhecidas. No capítulo 3, a adsorção de metais em constituintes dos solos provocou mudanças nas curvas espectrais dos mesmos, mostrando diferenças entre solos altamente contaminados por metais pesados e solos livres de contaminação. Os teores de Cr (semi-total) no solo pode ser predito através da espectroscopia de reflectância vis-NIR-mid-IR e regressão por mínimos quadrados parciais. Fe e Mn também foram preditos com acurácia usando dados vis-NIR. Em geral, os modelos de predição vis- NIR de metais pesados foram mais precisos que o mid-IR. A vantagem da utilização do sensor vis-NIR está no preparo mais simples de amostras e na possibilidade de utilizá-lo diretamente no campo.

Submitted by ANA FLÁVIA NUNES E REIS null (dra-anaflavia@uol.com.br) on 2016-01-26T19:16:31Z No. of bitstreams: 1 merged (4).pdf: 4937949 bytes, checksum: c052666784bd930ac4748e41040c73bd (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-01-28T13:31:20Z (GMT) No. of bitstreams: 1 reis_afn_me_sjc.pdf: 4937949 bytes, checksum: c052666784bd930ac4748e41040c73bd (MD5) / Made available in DSpace on 2016-01-28T13:31:20Z (GMT). No. of bitstreams: 1 reis_afn_me_sjc.pdf: 4937949 bytes, checksum: c052666784bd930ac4748e41040c73bd (MD5) Previous issue date: 2015-12-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste trabalho foi infiltrar sílica em uma cerâmica Y-TZP, avaliar seu efeito na resistência à flexão Biaxial, e na união com a porcelana feldspática. Para a análise da resistência à flexão foram confeccionados 180 discos de zircônia, 120 de 0,5mm e 60 com 1,2mm discos (14 mm de diâmetro). 90 discos foram infiltrados com sílica pelo método sol-gel em temperatura ambiente (n = 30). A espessura do disco foi de 1,2 mm para os espécimes controle (espécime sem porcelana, n = 30). O recobrimento por porcelana feldspática foi de duas espessuras (0,5mm e 1 mm) sobre a zircônia que tinha 0,5 mm. Os espécimes com porcelana foram polidos com lixas de carbeto de silício (SiC) de granulação # 400, 600, 800 e 1200. Obtivemos 6 grupos: dois monolíticos (ZR- Zircônia Monolítica sem infiltração e ZRI- Zircônia Monolítica Infiltrada) (controle) e quatro estratificados: ZRF 1,0 (0,5mm Zircônia coberta com 0,5 mm porcelana), ZRIF 1,0 (0,5 mm Zircônia infiltrada coberta com 0,5 mm de porcelana), ZRF 1,5 (0,5 mm Zircônia infiltrada coberta com 1,0 mm de porcelana) ZRIF 1,5- Zircônia infiltrada (0,5 mm Zircônia infiltrada coberta com 1,0 mm de porcelana). Após o ensaio de flexão biaxial em meio aquoso, foram determinados o módulo de Weibull (m) e resistência característica (σθ). Os fragmentos foram analisados em EDS, MEV, DRX e FTIR. A Dureza (H) e tenacidade a fratura foram analisadas pela nanoindentação, já o módulo elástico (E) por duas técnicas, nanoindentação e por impulso, e para avaliar a adesão entre a zircônia e a porcelana foi aplicado o Teste de Scratch. Foram modeladas 7 condições experimentais e analisados pelo método por elementos finitos. A zircônia monolítica infiltrada mostrou uma estrutura com grãos arredondados envoltos em uma matriz de sílica, e a presença de zircônia cúbica e tetragonal. O DRX revelou a formação de ZrSiO4 nos grupos infiltrados. Os grupos monolíticos apresentaram módulos de Weibull superiores aos dos grupos com porcelana. Com a análise (AEF) não houve diferença entre os grupos com a mesma espessura, já para o grupo recoberto com 0,5 mm de porcelana, os valores de tração e compressão foram maiores. A cerâmica infiltrada apresentou microestrutura diferente, e a adesão da porcelana à zircônia não-infiltrada foi superior à da zircônia infiltrada. / The objective was to infiltrate silica in a Y- TZP ceramics, evaluate its effect on resistance biaxial strenght, and the union with feldspathic porcelain. For the analysis of flexural strength were prepared zirconia discs 180, 120 and 60 of 0.5 mm to 1.2 mm disks (14 mm diameter). 90 discs were infiltrated with silica by the sol-gel method at room temperature (n = 30). The thickness of the disk was 1.2 mm for the samples control (no porcelain specimen, n = 30). The coating was feldspathic porcelain by two thicknesses (0.5 mm and 1 mm) of zirconia, which had 0.5 mm. Specimens with porcelain were polished with sandpaper silicon carbide (SiC) granulation # 400, 600, 800 and 1200. We obtained six groups: two monolithic (Zr-Zirconia Monolithic without infiltration and ZRI- Zirconia monolithic Infiltrated) (control) and four laminated ZRF 1.0 (0.5 mm zirconia covered with 0.5 mm porcelain), ZRIF 1.0 (0.5 mm infiltrated zirconia covered with 0.5 mm of porcelain), ZRF 1.5 (0.5 mm infiltrated zirconia covered with 1.0 mm of porcelain) ZRIF 1,5-infiltrated Zirconia (0.5 mm infiltrated zirconia covered with 1.0 mm of porcelain). After the biaxial bending test in an aqueous medium were determined Weibull modulus (m) and the characteristic strength (σθ). The fragments were analyzed by EDS, SEM, XRD and FTIR. The hardness (H) and fracture toughness were analyzed by nanoindentation, since the elastic modulus (E) by two techniques, nanoindentation and on impulse, and to evaluate the adhesion between the zirconia and porcelain was applied Scratch Test. 7 experimental conditions were modeled and analyzed by the finite element method. The infiltrated zirconia showed a monolithic structure with rounded grain wrapped in a silica matrix, and the presence of cubic and tetragonal zirconia. The XRD showed the formation of ZrSiO4 infiltrates in groups. The monolithic modules Weibull groups showed superior to porcelain groups. With the analysis (FEA) there was no difference between the groups with the same thickness, for now the group covered with 0.5 mm of porcelain, the tensile and compressive values were higher. The infiltrated ceramic showed different microstructure, and the accession of porcelain to non- infiltrated zirconia was higher than the infiltrated zirconia.

Resumo: O objetivo deste trabalho, dividido em dois estudos, foi avaliar: (1) a influência dos tipos de ponteiras (fibra óptica e polímero) utilizadas em um aparelho fotoativador à base de LED (Ultrablue IS - DMC) sobre o grau de conversão e dureza de uma resina composta microhíbrida (FiltekTM Z250) e uma nanoparticulada (FiltekTM Supreme XT); e (2) a influência dos tipos de ponteiras (fibra óptica e polímero) utilizadas em um aparelho fotoativador à base de LED (Ultrablue IS - DMC) sobre a resistência à compressão de uma resina composta microhíbrida (FiltekTM Z250) e uma nanoparticulada (FiltekTM Supreme XT). No primeiro estudo, para os testes de grau de conversão (GC) e dureza, cinco corpos-de-prova com 4 mm de diâmetro e 2 mm de espessura (ISO 4049), foram confeccionados para cada grupo avaliado. O grau de conversão foi analisado pelo Espectrofotômetro Nexus - 470 FT-IR. Para o teste de dureza Vickers, os corpos-de-prova foram levados ao Durômetro Micromet 2100 (Buehler, EUA) onde foi utilizada uma carga de 50 gramas força (gf) e tempo de 30 segundos. Para cada corpo-de-prova oito medidas foram realizadas nas superfícies de topo e base. Os dados obtidos para o GC e dureza foram analisados estatisticamente pelo teste de Análise de Variância (ANOVA) e Tukey. No segundo estudo, para o teste de resistência à compressão foram confeccionados oito corpos-de-prova com 8 mm de altura e 4 mm de diâmetro. O teste foi realizado na máquina de ensaio universal EMIC com célula de carga de 5 kN à velocidade de 0,5 mm/min. Os dados obtidos foram analisados estatisticamente pelo teste ANOVA e o teste Tamhane. Os resultados demonstraram que o GC e dureza foram influenciados pelas ponteiras, sendo a dureza também influenciada pelo tipo de resina composta utilizada. A resina composta microhíbrida fotoativada com a ponteira de fibra óptica apresentou maiores valores do GC e dureza... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this work, divided into two studies, was evaluate: (1) the influence of types of light guide tips (fiber optic and polymer) used in a photo-activation based on LED (Ultrablue IS - DMC) on the degree of conversion and hardness one microhybrid FiltekTM Z250 and one nanofilled FiltekTM Supreme XT composite resins; and (2) the influence of types of light guide tips (fiber optic and polymer) used in a photo-activation based on LED (Ultrablue IS - DMC) on the compressive strength of one microhybrid FiltekTM Z250 and one nanofilled FiltekTM Supreme XT composite resins. In the first study, to test the degree of conversion (GC) and hardness, five samples 4 mm in diameter and 2 mm in thickness (ISO 4049) were made for each group evaluated. The degree of conversion was evaluated by Fourier transform infrared spectroscopy (FT-IR). For the Vickers hardness test, the samples were brought to the durometer Micromet 2100 (Buehler, USA) where was used a load of 50 gram force (gf) and time of 30 seconds. For each sample test measurements were performed eigth measures on the surfaces of top and bottom. The data obtained for the GC and hardness test were statistically analyzed by Analysis of Variance (ANOVA) and Tukey's test. In the second study to test the compressive strength eight samples (4 mm in diameter and 8 mm in thickness) were made for each group evaluated, and the test was conducted in a universal testing machine EMIC with load cell 5 kN and speed of 0,5 mm/min. The data were statistically analyzed by ANOVA test and Tamhane's test. The results showed that the GC and hardness were influenced by the light guide tip, and the hardness also influenced by the type of resin used. The microhybrid composite resin photo-activated with the fiber optic light tip had higher values of GC and hardness. The lowest values of GC and hardness were observed with nanofilled composite resin photoactivated... (Complete abstract click electronic access below) / Orientador: Marcelo Ferrarezi de Andrade / Coorientador: Alessandro Nara de Souza Rastelli / Banca: Silmara Aparecida Milori Corona / Banca: José Roberto Cury Saad / Mestre

Made available in DSpace on 2014-10-09T12:42:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:29Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Os materiais reativos orgânicos, como turfas e compostos, apresentam um considerável potencial efetivo de utilização na remediação de áreas contaminadas por metais potencialmente tóxicos, haja vista sua elevada capacidade de adsorção, comumente associada a altos teores de matéria orgânica. O emprego do composto orgânico se torna vantajoso por ser uma possibilidade de destinação final correta dos resíduos sólidos urbanos compostáveis, conforme as políticas públicas, podendo agregar valor econômico e ambiental ao resíduo. Nessa perspectiva, na seleção dos materiais reativos mais viáveis para serem empregados na retenção de metais é imprescindível sua caracterização (geológica e geotécnica) e o estudo de sua real capacidade adsortiva, através de ensaios de adsorção. Assim, o objetivo desta pesquisa foi a caracterização geológica e geotécnica de uma turfa (proveniente da bacia hidrográfica do rio Mogi Guaçu, município de Cravinhos) e de quatro compostos (compostos total, indiano, estático e alambrado, advindos de composteiras localizadas na Universidade de São Paulo - São Carlos), bem como ensaios de adsorção (equilíbrio em lote) com chumbo (Pb), zinco (Zn) e cádmio (Cd). Para tanto foram realizados os seguintes ensaios de caracterização: granulometria, massa específica dos sólidos, densidade, teor de umidade, parâmetros físico-químicos (potencial hidrogeniônico (pH), &Delta;pH, potencial de oxi-redução (Eh) e condutividade elétrica (CE), ponto de efeito salino nulo (PESN), matéria orgânica (MO), teor de cinzas (Cz), capacidade de troca catiônica (CTC), capacidade de retenção de água (CRA), composição elementar (C, H e N), carbono orgânico, Difratometria de Raios-X (DRX), Fluorescência de Raios-X (FRX), Microscopia Eletrônica de Varredura/Espectroscopia de Energia Dispersiva por Raios-X (MEV/EDS) e Análise Térmica Diferencial (ATD). A partir do conhecimento minucioso dos parâmetros físicos e químicos dos materiais foi possível proceder o ensaio de equilíbrio em lote com soluções monoelementares de Pb, Zn e Cd com oito concentrações distintas e inferiores a 220 mg L-1 e razão material reativo/solução de 1/50 (conforme definido em etapa preliminar). Quanto aos resultados de caracterização, turfa e compostos apresentaram características promissoras para a adsorção. A turfa revelou um pH moderadamente ácido (5,1), um &Delta;pH negativo (-1,0) atestando para a presença majoritária de cargas negativas na superfície das partículas, o que foi confirmado pelo PESN (3,6) < pH (5,1), um considerável teor de MO (520,43 mg kg-1) e uma CTC elevada (91,00 cmolc kg-1). Já os compostos exibiram valores de pH ligeiramente ácidos a ligeiramente básicos (6,4 a 7,7), &Delta;pH negativo (-0,4 a -1,0), MO promissora (193,92 a 418,70 mg kg-1) e CTC variável (29,00 a 75,00 cmolc kg-1). Em termos gerais, os compostos total e indiano apresentaram características mais favoráveis para a retenção metálica o que foi confirmado por etapa preliminar do ensaio de adsorção. Como o composto indiano sobressaiu levemente na imobilização de Cd e Zn e por ele apresentar maior controle no processo de compostagem ele foi o escolhido para a realização do ensaio de equilíbrio em lote com variadas concentrações de Pb, Zn e Cd, assim como a turfa. Os resultados finais de adsorção atestaram que a turfa e o composto indiano apresentaram a mesma ordem de afinidade metálica: Pb > Cd > Zn, sendo que o composto revelou uma tendência superior de adsorção. A turfa revelou uma porcentagem de remoção metálica (A%) superior a 90% para concentrações de Pb de até 137 mg L-1, enquanto o composto adsorveu mais de 98% do Pb em todas as concentrações estudadas (26 a 214 mg L-1), não atingindo o estado de saturação. Dessa forma, turfa e compostos, caracterizados por um baixo custo e uma significativa disponibilidade, podem ser enquadrados como potenciais materiais reativos orgânicos para a imobilização de cátions metálicos, principalmente Pb2+ e Cd2+. / Organic reactive materials, such as peat and compounds, have a considerable potential for use in the remediation of contaminated areas by potentially toxic metals, due to their high adsorption capacity, commonly associated with high organic matter content. The use of organic compound becomes advantageous because it is a possibility of final destination for the compostable municipal solid waste, according to the public policies, being able to add economic and environmental value to the waste. In this perspective, the selection of the most viable reactive materials to be used in the retention of metals is needful, its characterization (geological and geotechnical) and the study of its real adsorptive capacity through adsorption tests are essential. Thus, the objective of this research was to characterize the geological and geotechnical characteristics of a peat (from Mogi Guaçu\'s basin in the city Cravinhos) and four compounds (total, indian, static and wired, from composters located at the University of São Paulo), besides batch tests with lead (Pb), zinc (Zn) and cadmium (Cd). To achieve the objectives, the following tests were done: particle size analysis, solids specific mass\' determination, density, moisture content, physico-chemical parameters (potential hydrogenion - pH, &Delta;pH, oxy-reduction potential - Eh and electrical conductivity - EC), point of zero salt effect (PZSE), organic matter (OM), ash content, cation exchange capacity (CEC), water retention capacity (WRC), elemental composition (C, H and N), organic carbon, X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscopy/X-Ray Dispersive Energy Spectroscopy (SEM/DES) and Differential Thermal Analysis (DTA). From the detailed knowledge of the physical and chemical parameters of the materials was possible to perform the batch equilibrium test with monoelemental solutions of Pb, Zn and Cd with different concentrations below 220 mg L-1 and reactive material/solution ratio of 1/50 (as defined in the preliminary stage). Regarding the characterization results, peat and compounds presented promising characteristics for adsorption. The peat showed moderately acidic pH (5.1), negative &Delta;pH (-1.0) attesting to a majority presence of negative charges on the surface of the particles, which was confirmed by the PZSE (3.6) < pH (5.1), a considerably high OM content (520.43 mg kg-1) and a high CEC (91.00 cmolc kg-1). The compounds exhibited from slightly acidic to slightly basic pH values (6.4 to 7.7), negative &Delta;pH (-0.4 to -1.0), promising OM (193.92 to 418.70 mg kg-1) and variable CEC (29.00 to 75.00 cmolc kg-1). In general, terms, the total and indian compounds presented more favorable characteristics for metal retention, what was confirmed by the preliminary step of the adsorption test. As the Indian compound had a small enhancement on the immobilization of Cd and Zn and due, it showed greater control in the composition process, it was chosen for a batch equilibrium test with varying concentrations of Pb, Zn and Cd, as well as a peat. The final adsorption results showed that the peat and the indian compound had the same order of metal affinity: Pb > Cd > Zn, whereby the compound showed a higher adsorption tendency. The peat showed a metal removal percentage (A%) higher than 90% for Pb concentrations up to 137 mg L-1, while the compound adsorbed more than 98% at all concentrations studied (26 to 214 mg L-1) not reaching the saturation state. Thus, peat and organic compounds, characterized by a low cost and a significant availability, can be classified as potential organic low-cost reactive materials for metal cations immobilization, mainly Pb2+ and Cd2+.