Dissertações em Geologia e Geoquímica (Mestrado) - PPGG/IG

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2604

O Mestrado Acadêmico pertence ao Programa de Pós-Graduação em Geologia e Geoquímica (PPGG) do Instituto de Geociências (IG) da Universidade Federal do Pará (UFPA).

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Adsorção de cromato em materiais sintetizados a partir de rejeito de caulim do rio Capim
(Universidade Federal do Pará, 2008-05-13) MORAES, Milena Carvalho de; LEMOS, Vanda Porpino; http://lattes.cnpq.br/1829861620854008
Industrial and domestic waste cause serious problems for the environment. Industries treatment of kaolin have been deposited reject in large lakes of sedimentation and this has caused accidents as occurred in august/2007 and February/2008. The large volume of kaolin in the lakes sedimentation invaded lakes and rivers from Rio Capim, Para region. This fact resulted in the pollution of waters and death of fish. This problem can be minimized with the use of kaolin reject (KR) in the synthesis of new materials. In this work was used KR treated with organic acid (glycine at concentrations of 5%, 10% and 15% , being obtained the adsorbents: KR-gly-5, KRgly-10 and KL-gly-15, respectively) and mixture NaClO4:HClO4 (proportions 1:50 and 1:75, being obtained the adsorbents KR-NaClO4:HClO4-1:50 and KR- NaClO4:HClO4- 1:75, respectively) and KR as source of Si and Al in the synthesis of zeolites. The materials were characterized by chemical composition and XRD, FTIR, DTA-TG and SEM data. These materials were studied in adsorption process for CrO4 2- from aqueous solutions. The results obtained indicate that the CrO4 2- is adsorbed by kaolin reject and other materials from KR followed this order: KR-gly-10> KR-gly-5>KR-gly-15>KG> KR- NaClO4:HClO4- 1:75> zeolites.
Acesso aberto (Open Access)
Adsorção de Pb por caulinita tratada com ácidos acético e cítrico
(Universidade Federal do Pará, 2005) SENA, Luciana Freitas de; LEMOS, Vanda Porpino; http://lattes.cnpq.br/1829861620854008
Acesso aberto (Open Access)
Beneficiamento de uma argila tipo palygorskita da Bacia de São Luis-Grajaú, região de Alcântara (MA) e sua utilização como adsorvente de fósforo.
(Universidade Federal do Pará, 2012-09-04) ARRUDA, Gabriela Monice; NEVES, Roberto de Freitas; http://lattes.cnpq.br/9559386620588673
The estimated contribution of the industry minerals in Brazil is about 70% of National Mineral Production Value. These minerals are important because of its diverse applications. Among them, in clay minerals group, there is palygorskite, which presents the requirements to join special clays group, once their occurrence is restricted. Thus, this new mineral occurrences deserve attention and further study. Adding to this, there is the fact in the Amazon region, as well as in most areas of tropical and temperate zones, the acidity is an important factor in land degradation and represent one of the major problems faced by agriculture. Acid soils have several limitations, which hinders the use of nutrients, requiring the addition of fertilizers, always aiming maximum efficiency. In this context, this study used a sample from the Bacia de São-Luis-Grajaú, Maranhão State, consisting of a mixture which is predominantly palygorskite and dolomite, approaching the existence of this new occurrence, suggesting a processing method and its application as phosphorus adsorbent, once dolomite is a pH soil corrector, while palygorskite has the function of nutrients carrier. First, chemical and mineralogical characterizations were performed, by XRD, XRF, SEM and separation of sand, silt and clay fractions. Sedimentation and phosphorus adsorption experiments were also performed, with determination of kinetic curve. After the analysis of XRD, results shown that the sample consists mainly of palygorskite and dolomite. Illite, chlorite and quartz are also presented. It was also possible to see that the different types of disaggregation used showed no significant differences in the diffractograms of the samples. The sand-silt-clay separation, although only based on the size of the material, showed a reasonable efficiency for material separation, as the sedimentation tests, where it was noticed that after a 24 hours period, dolomite had disappeared from the supernatant. Determination of kinetic curve revealed that the adsorption period of 2 hours is not sufficient for phosphorus adsorption, requiring 24 hours to reach the reaction equilibrium. Sorption tests showed efficiency higher than 91% of the initial phosphorus present in solution, and the maximum quantity adsorbed per gram of sample was 0.607 mg. The correlation with the adsorption isotherm models studied, showed better results for Langmuir-Freundlich isotherm, with correlation coefficient of 0.9993, which can be attributed to the fact that adsorption occurs in more than one layer.
Acesso aberto (Open Access)
Caracterização química, mineralógica e aplicações potenciais da bentonita associada a basaltos intemperizados da Formação Mosquito, Bacia do Parnaíba, Sul do Maranhão
(Universidade Federal do Pará, 2010-03-01) PAZ, Simone Patrícia Aranha da; NEVES, Roberto de Freitas; http://lattes.cnpq.br/9559386620588673; ANGÉLICA, Rômulo Simões; http://lattes.cnpq.br/7501959623721607; https://orcid.org/0000-0002-3026-5523
In the city of Formosa da Serra Negra (Maranhão state, northern Brazil), extensive outcrops of weathered basalts are found, which show enough clay contents to be a potential bentonitic material. The basalts are related to the Jurassic Mosquito Formation (Parnaíba Sedimentary Paleozoic Basin). In this work these saprolites were referred as Formosa bentonite, and the main purpose was to characterize their mineralogical and chemical composition for further potential applications. X-ray diffraction results show that montmorillonite is the main mineral present along with minor amounts of hematite, K-feldspar, magnetite and kaolinite. The Formosa Bentonite was compared with four reference bentonites: Chocolate and Bofe (from the famous Paraiba state deposits), SWy-2 and SAz-1 (from the Clay Mineral Society). Although these bentonites have showed a wide chemical, mineralogy and texture variation, common for such material, the similarities were convincing to increase the expectations of a new Brazilian bentonite. The present montmorillonite was successfully pillared with aluminium polyhydroxications. Results showed that the pillarization process increased the basal spacing of the natural clay from 15.3 to 18.7 Å and the surface area from 55.9 to 180.3 m2/g, proper for catalytic and adsorption applications. Adsorption tests were also carried out for Cu2+ in aqueous solution using the natural and pillared Formosa Bentonite. Surprisingly, in the three evaluated process variables (pH, contact time and adsorption equilibrium) the natural bentonite exhibited a better adsorptive capacity in comparison with the pillarized one. This is of special value if one intends to use these bentonites in natura, for instance, for wastewater treatment. They are environmentally correct, economically viable and assure low cost.
Acesso aberto (Open Access)
Potencialidade adsorvente da zeólita A derivada de rejeito de caulim na remoção de corantes
(Universidade Federal do Pará, 2017-10-18) ARAÚJO, Leiliane Cristina Cardoso; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568
In the States of Pará and Amapá are the largest Brazilian reserves of kaolin. The process of beneficiation of this material generates a significant volume of waste, this is kaolin that is out of the specifications for paper coverage and ends up becoming an environmental liability, since large areas are required to be deposited. This reject consists mainly of the kaolinite clay that presents Si and Al in a ratio of 1: 1, ideal to be used as raw material in the synthesis of zeolites. Zeolite A is a microporous synthetic aluminosilicate, easily synthesized from kaolin waste, making it a low cost and effective material to remove contaminants present in the effluents, such as dyes, besides having a high degree of selectivity and other characteristics that make it an excellent adsorbent. Among the most used processes in the dye removal is the adsorption, because it has several advantages such as: low cost, high removal rates and the possibility of adsorbent recovery. The work methodology was carried out in four stages: 1) Zeolite A synthesis: the Tube Press kaolin was used as starting material from the company located in the Capim-PA River, which was subsequently calcined at 700 ° C for 2h, solution of NaOH (5 mols L-1) and distilled water. They were kept in a reactor for 2 h at 95 ° C under stirring. After the synthesis the material was washed to pH = 7 and dried. Both the starting material and the products were identified and characterized by DRX, MEV, DTA-TGA and granulometric analysis. 2) The adsorption study was performed with AM and VC dye solution at concentrations of 2-26mg L-1. The equilibrium, adsorption kinetics and thermodynamics were obtained. The tests were done in a batch system and the solutions after adsorption were analyzed in UV-Visible spectrophotometer, using λ = 585nm for AM and λ = 665nm for VC. 3) Zeolite A regeneration was performed with 50 ml of the dye solution in the concentration 10 mg L -1 and 150 mg zeolite A. After 24 h the suspension was centrifuged, the supernatant analyzed and the solid dried and then calcined at 650 °C for 2 h to a five-fold cycle. 4) Desorption study: 50 ml of AM and VC dye solution at 10 mg L-1 and 150 mg zeolite A, after adsorption of 24 h the solid was separated by centrifugation and the water and methanol solvents were subsequently added in five proportions to give the initial volume of 50 ml and kept under stirring for 24 hours and after analysis of the supernatant in UV-Visible spectrophotometer. In the results of the adsorption equilibrium, the percentage of adsorption decreases with increasing concentration, as more dye molecules are incorporated into the adsorbent, reducing the area and the available active sites. The maximum adsorption capacity at equilibrium for MA was 5.1 mg g-1 and for the CV of 14.09 mg g-1, in this way the equilibrium adsorption capacity was higher for the CV as compared to the MA. The mathematical model that best fit the experimental data of AM equilibrium was the Sips isotherm that combines characteristics of the Langmuir and Freudlich isotherms, whereas for the VC dye the best model is that of Freudlich suggesting that adsorption occurs in multilayers. The adsorption kinetics of AM and VC were adjusted to the pseudo second order model. The thermodynamics of adsorption of AM at temperatures of 30 °C to 70 °C is a spontaneous process, favored at higher temperatures. The thermal regeneration of zeolite A after 5 cycles of regeneration had a loss in the efficiency of the AM adsorption in 7% and 3% for the CV, indicating the possibility of reuse of the adsorbent. Desorption with the 50% mixture of each solvent showed the best results.
Acesso aberto (Open Access)
Síntese de zeólitas A e 5A a partir de caulim: uma comparação dos métodos de síntese estático e dinâmico
(Universidade Federal do Pará, 2011-05-11) SANTOS, Suzianny Cristina Arimatéa; NEVES, Roberto de Freitas; http://lattes.cnpq.br/9559386620588673
Greater awareness of environmental issues and policies on conservation have been doing that arise with new proposals for waste recycling. One of those ways is to reuse the employment of the tailing of the beneficiation of kaolin in zeolite synthesis from kaolin tailing, because zeolites have a wide applicability. Zeolite 5A was synthesized by cation exchange using as starting material zeolite A and calcium solution. We have developed a process for synthesis of zeolite A and zeolite 5A, and the kinetic monitoring of obtaining these crystalline phases and scaling of zeolites A and 5A. The following methods were used: XRD, XRF, SEM, DTA-TG and sieve analysis. It was found that using the two methods of synthesis were obtained zeolites A and 5A, but with only variations in the intensities of their peaks, where the synthesized zeolites in dynamic method showed greater intensity and a greater possibility of scaling up production to 400g. The products were used in zeolite adsorption system, the adsorption tests of moisture in the air the same show promise, arriving adsorb up to 20% on the mass of zeolite. It was found that the new dynamic methodology developed for production of zeolite A in this work proved to be much higher than the previous static approach, because it allowed a greater increase in scale beyond the reduction of synthesis time.
Acesso aberto (Open Access)
Síntese e caracterização da piroaurita a partir de resíduo de mina de cobre e sua aplicação na adsorção do corante vermelho do Congo
(Universidade Federal do Pará, 2023-03-24) FERREIRA, Rafaela da Silva; RODRIGUES, Elizabeth Maria S.; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568
In this study, the copper flotation tailings extracted from the Sequeirinho pit of the Sossego mine, Carajás region, Southeast of the State of Pará (Brazil), has been used as raw material for the synthesis of Pyroaurite, a potential absorbent of organic dyes. Initially, tailings characterization was performed through X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) techniques. Next, a sample of this characterized material was leached (HCl 1:1 H2O), the obtained solution was filtered and used in the procedures of Pyroaurite synthesis. This solution was kept in the coprecipitation method at constant pH (14) with Mg/Fe molar ratio equal to 6:1, a dripping time of 4 hours, hydrothermal bath of 24 hours at high agitation rate. After, the synthesized Pyroaurite was submitted to characterization by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), Specific Surface Area (ASE) and total pore volume (Wo) techniques. Then, the synthesized Pyroaurite was evaluated for the adsorption process of Congo Red (CR) dye, where 0.025 mg of Pyroaurite were added to 10 mL of CR samples at concentrations of 5, 10, 20, 30, 40, 50 and 80 mg·L-1, respectively. The adsorption results fitted to the Langmuir model (R2 = 0.9614), while the kinetics suggested the pseudo-second order model (R2 = 0.9977). In addition, the temperature of 40ºC showed to be the most pleasant for the adsorption of the CR dye. Finally, the thermodynamic parameters of entropy (ΔSº= 0.0886 kJ·mol-1·K-1) and enthalpy (ΔHº= 8.2999 kJ·mol-1) show that the adsorption process was found to be naturally spontaneous and endothermic.
Acesso aberto (Open Access)
Síntese, caracterização físico-química e aplicação de alumínossilicatos como adsorventes
(Universidade Federal do Pará, 2003-05) CASTRO, Elton Anderson Santos de; LEMOS, Vanda Porpino; http://lattes.cnpq.br/1829861620854008
In this work three differente aluminosilicates were used for evaluation of the index of recovery of the coloring monovalent metilene blue. The no-porous clay mineral, Kaolinite, from Capim river area in Pará, Brazil, was treated with hydrochloric acid 5N in order to increase the specific area. The microporous molecular sieve, zeolite NaP, was synthesized through the hidrotermal method, with the kaolinite of Capim river area being used as source of Si and Al. The hidrotermal method was also used for the synthesis of the mesoporous molecular sieve Al-MCM-48, wich received thermal treatment (calcination) at 540ºC under flow of N2 and air for 7h to removal of the agent director (surfactant). The porous and no-porous materials were characterized by X-ray diffraction, infrared spectrophotometry, thermodifferential and termogravimetric analyses and adsorption and desorption methods with N2. Chemical analysis for the clay mineral has been performed and scanning electronic microscopy was used for the microporous aluminosilicate. These materials were tested as adsorbents in the recovery of the metilene blue at concentration of 6ppm, in different times (20, 40, 60 and 120min) with the contact method being used. The concentration, separation method of phases and the more appropriate wave length were studied. The determination of the recovery index for the organic coloring, using the three materials, was performed through visible spectrophotometry. XRD and chemical analysis results revealed the high purity of the clay mineral kaolinite. The specific surface area increased by 31,23% after acid activation. The specific area obtained for Al-MCM-48, was of 1219m2g-1, which is a characteristic value for this kind of materials. The results of XRD indicate that the zeolita NaP was formed, but traces of the feldspatoid hidroxysodalite are also present, what could be confirmed by the SEM images. The values of the recovery index for the metilene blue demonstrated that the kaolinite under acid activation was the most effective (100% of recovery), followed by the zeolite NaP (97,89% of recovery) and Al-MCM-48 (97,35% of recovery). The results indicate the viability of use of these materials as agents for pre-concentration in cromatographic analyses.
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Sorção de Ni e azul de metileno em esmectita do Rio Branco-Acre sob tratamento com cátion orgânico
(Universidade Federal do Pará, 2008-03-19) SILVA, Tatiani da Luz; LEMOS, Vanda Porpino; http://lattes.cnpq.br/1829861620854008
The interaction among organic cations, as the methylene blue (AM), benzyltrimethylammonium (BTMA) and clay minerals of the group of the smectites they result in the formation of applied materials in the adsorption of organic pollutant presents in waters, soils and you cultivate. In this work they were prepared the adsorbents (organic–clays) smectite - AM and smectite–BTMA, with the following objectives: the use of the clay minerals covering observed at several places of the municipal district of Rio Branco – Acre, as organic-clay precursor, with applicability of absorption of heavy metals and organic substances; the principal chemical and mineralogical attributes of the precursory clay determination, that are necessary requirements the interpretation of the mechanisms of interaction organic clay/cation and metallic organic-clay/cation; the study of the processes of adsorption of the organic-clays; the evaluation of the efficiency of the organic - clays in the nickel adsorption. The precursory sample of smectite was collected in Rio Branco–Acre, being used in the tests of adsorption and in the treatment with the organic cations the fraction clay mineral (F-Esmec) and the total fraction (FT-IR) of the sample. They were also used an smectite sample collected in Sena Madureira (SM)–Acre already characterized in previous work and a sample of standard smectite Swy-2-Na-Montmorillonite (SWy-2) of Wymong - USA. The mineralogical analysis was accomplished with base in the data of difraction of DRX, to FT-IR, MEV and ATD-ATG. The organic agents selected for this study they were: Methylene Blue, denominated AM and Benzyltrimethylammonium, denominated BTMA. The interaction processes between clay and organic cations were investigated through data obtained by molecular spectroscopy in the area of IV, ATD-ATG, MEV and DRX. The adsorbents were applied in the adsorption of AM and Ni in aqueous head offices (concentrations varying from 1 to 10 ppm). The concentrations of AM and Ni before and after the adsorption they were certain for spectrophotometry in the area UV for AM (λ= 670 nm) and for atomic absorption for determination of the concentration of Ni (λ = 232 nm). The clay sample collected in Rio Branco–Acre is constituted mainly by quartz, the most abundant, smectite, illita and caulinita, and of the clay minerals the smectites are the predominant ones in the clay sample. The basal spacings of the samples didn't change significantly with the adsorption of AM and of BTMA, as observed in works found in the literature. They were appraised the capacities adsorptive of the treated samples with BTMA being used AM as adsorvate. The results of these evaluations detected that ran total adsorption of AM (concentrations varying from 1 to 10 ppm) for the treated samples with BTMA, being also this behavior verified in experiences accomplished for: Gersti and Mingelgrin (1979), Mortland (1979), Boyd et al (1988), Margulies et al (1988), that in your studies evidence the organophilic interactions. Like this being, the samples presented plausible results as the adsorption of Ni and AM, being the clays of precursory of the organic-clays good Acre: smectite–AM and smectite–BTMA. In the tests of adsorption accomplished with solutions Ni2+ the amount adsorved (mg.g-1) it happened in the following order: F-Esmec-BTMA > F-Esmec. The organic cation, BTMA, interacting with the surfaces of the natural clay was more efficient in the adsorption of AM than the clay without the previous treatment with this salt. To evaluate the time that the sample F-Esmec should be in contact under agitation with the solution of Ni, three isotherms of adsorption were accomplished, where the time of agitation of the solution of Ni in contact with the clay varied in 1h, 12hs and 24 hs. The experiments showed that 1h are the enough time that the sample should be under agitation with the solution of Ni to obtain good results of adsorption because the value of Q, in mg/g, of Ni adsorbed after 24 h of agitation of the solution was practically the same obtained under agitation by 1h. The treatment of the clay with BTMA increased an amount adsorbed of the present nickel in aqueous solutions, as well as happened him in the tests of adsorption with AM. This is due the existent specific interactions between adsorbent and adsorvate, as foreseen by Gersti and Mingelgrin (1979). In all the tests of adsorption, the fraction F-Esmec was the one that it presented better result of adsorption.

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