JULIANA DE CARVALHO IZIDORO

JULIANA DE CARVALHO IZIDORO

Página do item completo

Resultados de Busca

Agora exibindo 1 - 10 de 41

Zeolites synthesized from agro-industrial residues applied in agriculture: A review and future prospects
2023 - IZIDORO, JULIANA de C.; FUNGARO, DENISE A.; CATALDO, ELEONORA
Zeolites have been widely applied as catalysts, wastewater treatment agents, gas adsorbents and fertilizers, among others. However, the use of natural zeolites or those synthesized from oversaturated commercial solutions are more explored commercially than the zeolites synthesized from residues. Therefore, the aim of this review is to highlight the importance of zeolites synthesized from agroindustrial residues and their use in agriculture. This review has been divided into three different sections, that is, zeolites, agriculture applications, synthesis of zeolites from residues and their application in plant growth. In the first section, the definition, types and the critical properties of zeolites are explained. The second section gives a brief review of the application of zeolites in agriculture. Finally, the synthesis of zeolites from residues, such as coal ash, rice husk ash and sugarcane ash, with special attention to renewable sources is presented. The optimization of the synthesis of zeolites from residues with the incorporation of specific nutrients necessary for the cultivation of soybeans, corn and sugarcane (considered the most significant crops in Brazilian agriculture in terms of the planted area) can significantly contribute to the concept of circular economy at the industries and the fulfilment of sustainable development objectives, especially, the number 12 (SDO—12—Responsible consumption and production).
Trace elements in coal, coal combustion products and soil from coal-fired power plant area evaluated by neutron activation analysis
2021 - FUNGARO, D.A.; SILVA, P.S.C.; IZIDORO, J.C.; HOWER, J.C.
The concentrations of trace elements were determined in coal, fly ashes from baghouse and cyclone filter, and bottom ash from the Figueira thermal power plant (FPP) by a neutron activation analysis technique. Study of the enrichment factor indicated that coal ashes were moderately enriched for all elements, except for Zn that exhibits significant to very-high enrichment. The mobilization of elements was observed in the zeolite products obtained from the three coal ashes. With regards to the amount present in each type of ash, most of the elements were present at same level in zeolites, with the exception of As which exhibited much lower concentration. The trace element concentrations of two soil samples collected in the vicinity of the FPP was also investigated. The results indicate that the FPP contributes mainly to the Zr and Ba pollution in nearby soils, particularly Zr pollution.
A avaliação da eficiência da zeólita na remoção do íon amônio numa solução sintética
2015 - STELLATO, THAMIRIS B.; SILVA, TATIANE B.S.C. da; VILLA, SABRINA M.; MARQUES, JOYCE R.; FAUSTINO, MAINARA G.; SILVA, DOUGLAS B. da; MONTEIRO, LUCILENA R.; IZIDORO, JULIANA C.; COTRIM, MARYCEL E.B.; PIRES, MARIA A.F.
A proposta deste estudo é avaliar a eficiência da zeólita na remoção do íon amônio numa solução sintética, para sua posterior aplicação em sistemas de tratamentos de efluentes.
Application of high-purity zeolite a synthesized from different coal combustion by-products in carbon dioxide capture
2019 - IZIDORO, JULIANA; CASTANHO, DAVI; ROSSATI, CARLOS; FUNGARO, DENISE; GUILHEN, SABINE; NOGUEIRA, THIAGO; ANDRADE, MARIA de F.
High-purity zeolites A were synthesized from different coal combustion by-products (baghouse filter fly ash, cyclone filter ash, and bottom ash) and characterized in terms of morphology, chemical, and mineralogical composition. The products were tested for carbon dioxide capture by using a continuous CO2 flow system passing through a column packed with the adsorbent material, which was connected to an analyser that directly measures the concentration of CO2. The values of CO2 adsorption capacities calculated for the unmodified Na-A zeolites (ZABF, ZACF, and ZABA) were 556.48, 494.29 and 654.82 mg g–1, respectively. These values were higher than those achieved by the calcium-modified zeolite samples. ZABA adsorbent presented the best performance in CO2 capture when compared to the other adsorbent material and achieved an adsorption capacity 32% higher than a 4A commercial zeolite. In the adsorption cycles study, the percentage of CO2 desorption by ZABA at the second and third cycles reached 93%, showing that zeolite A can be regenerated by heating at 150 ºC. The use of coal ashes to obtain zeolites and the application of these products for the CO2 adsorption can be an important strategy to mitigate both the problem of waste management and the greenhouse gases emission in coal-fired power plants.
Synthesis of nanocrystalline zeolite Na-A from coal fly ash and different aluminum sources
2018 - FUNGARO, DENISE A.; IZIDORO, JULIANA C.; GUILHEN, SABINE N.; SILVA, KATIA C.; WANG, SHAOBIN
This chapter describes the synthesis process to obtain zeolite Na-A from coal fly ash via fusion with NaOH followed by hydrothermal reaction. Coal fly ash is a low cost source of both silica and alumina. The molar ratio of SiO2/Al2O3 for zeolite 4A formation was achieved by the addition of sodium aluminate solution or aluminum waste from tertiary industry as aluminum sources. The effects of temperature and time at the fusion step and the hydrothermal reaction time on crystalline products were investigated. The synthesized products were studied for their purity and yield as well as were characterized by different techniques such as Xray powder diffraction (XRD), scanning electron microscopy (SEM) and cation exchange capacity (CEC), among others. Analysis of the properties of the raw materials and the products demonstrates that the by-products can be used to produce a high purity zeolite A. The optimum conditions related to the synthesis was set and the samples were pure, highly crystalline and white. The synthesized zeolites were used for both the removal of Cd (II) and Zn (II) from aqueous solution. The results showed that coal fly ash and aluminum source can be transformed into zeolite A, which is considered as value-added material with adsorption properties.
Evaluation of radionuclide contamination of soil, coal ash and zeolitic materials from Figueira Thermoelectric Power Plant
2019 - FUNGARO, D.A.; SILVA, P.S.C.; CAMPELLO, F.A.; MIRANDA, C.S.; IZIDORO, J.C.
The feed pulverized coal used at Figueira thermoelectric power plant (FTPP) presents a significant amount of uranium concentration and the potential radiological impact pathways into the surrounding environments should be monitored frequently. Neutron activation analysis was used to determine 238U and 232Th, and gamma-ray spectrometry was used to determine 226Ra, 228Ra, 210Pb and 40K contents present in coal, different types of coal ashes, their synthesized zeolites and two different soil samples collected in the vicinity of FTPP as well as, radiological indices to determine possible health effects due to radiation exposition. The natural radionuclide concentrations in pulverized coal were 216 Bq kg–1 for 238U, 180 Bq kg–1 for 226Ra, 27 Bq kg–1 for 228Ra, 28 Bq kg–1 for 232Th and 192 Bq kg–1 for 40K. The ashes fraction presented concentrations ranging from 683.5 to 1479 Bq kg–1 for 238U, from 484 to 1086 Bq kg–1 for 226Ra, from 291 to 1891 Bq kg–1 for 210Pb, from 67 to 111 Bq kg–1for 228Ra, from 80 to 87 Bq kg–1 for 232Th and from 489 to 718 Bq kg–1 for 40K. Similar ranges were observed for the different zeolitic products. The activity concentration of 238U was higher than worldwide average concentration for all samples. The concentration of the uranium series found in the ashes was lower than the values observed in similar studies carried out 10 years ago and under the limit adopted by the Brazilian guideline (CNEN-NN-4.01). The radiological indices indicated that the environmental disposal of fly ashes may represent a risk for public health, therefore, the resulting data can be used for systematic studies on radiological implication due to the release of TENORM caused by coal-fired power plant.
Treatment of coal ash landfill leachate using zeolitic materials from coal combustion by-products
2018 - IZIDORO, JULIANA de C.; MIRANDA, CAIO da S.; GUILHEN, SABINE N.; FUNGARO, DENISE A.; WANG, SHAOBIN
Three different zeolitic materials derived from coal combustion by-products (CCBs) were used to treat local coal ash landfill leachate at the same power plant. The zeolitic materials properties were characterized in terms of mineralogical composition (XRD), chemical composition (XRF), total carbon content, morphological analysis (SEM), specific surface area (BET method), cation exchange capacity (CEC), loss of ignition, pH, conductivity and bulk density. XRD indicated that sodalite zeolite was formed in all the samples after hydrothermal activation of CCBs. One zeolitic product from baghouse fly ash (ZFB) presented the lowest SiO2/Al2O3 ratio, highest CEC and specific surface area, thus having a high capacity in removal of heavy metal pollutants. The zeolitic products were efficient to reduce arsenic concentration to a value below the legislation. All zeolitic materials also showed a significant removal of Ni, Cd, Zn and Co except of Cr at a dose of 10 g L-1. Thus, this work provides a sustainable strategy to resolution of solid waste from power plants.
Evaluation of radionuclide contamination of soil, coal ash and zeolitic materials from figueira thermoelectric power plant
2017 - FUNGARO, DENISE A.; SILVA, PAULO S.C. da; CAMPELLO, FELIPE A.; MIRANDA, CAIO da S.; IZIDORO, JULIANA de C.
Neutron activation analysis and gamma-ray spectrometry was used to determine 238U, 226Ra, 228Ra, 210Pb, 232Th and 40K contents in feed pulverized coal, bottom ash, fly ash from cyclone and baghouse filters, zeolites synthesized from the ashes and two different soil samples. All the samples used in the study was collected at Figueira thermoelectric power plant, located in the city of Figueira, Paraná State, which coal presents a significant amount of uranium concentration. The natural radionuclide concentrations in pulverized coal were 4216 Bq kg–1 for 238U, 180 Bq kg–1 for 226Ra, 27 Bq kg–1 for 228Ra, 28 Bq kg–1 for 232Th and 192 Bq kg–1 for 40K. The ashes fraction presented concentrations ranging from 683.5 to 1479 Bq kg–1 for 238U, from 484 to 1086 Bq kg–1 for 226Ra, from 291 to 1891 Bq kg–1 for 210Pb, from 67 to 111 Bq kg–1for 228Ra, from 80 to 87 Bq kg–1 for 232Th and from 489 to 718 Bq kg–1 for 40K. Similar ranges were observed for zeolites. The activity concentration of 238U was higher than worldwide average concentration for all samples. The concentration of the uranium series found in the ashes were lower than the values observed in similar studies carried out 10 years ago and under the limit adopted by the Brazilian guideline (CNEN-NN-4.01). Nevertheless, the concentrations of this specific area are higher than others coal mines and thermoelectric power plants in and out of Brazil, so it is advisable to evaluate the environmental impact of the installation.
Otimização da síntese de zeólita na-a de elevada pureza obtida a partir de cinzas volantes de carvão
2017 - ROSSATTI, CARLOS; CASTANHO, DAVI; IZIDORO, JULIANA de C.; FUNGARO, DENISE A.
A queima do carvão mineral para a produção de energia elétrica gera diversos tipos de resíduos. Entre os resíduos gerados, encontram-se os seguintes tipos de cinzas: leves e pesadas. No Brasil, as cinzas volantes e leves correspondem a 85% do total de cinzas produzidas, enquanto que as cinzas pesadas correspondem a somente 15%. Uma das formas de mitigar o impacto ambiental proveniente da disposição inadequada das cinzas é o desenvolvimento de metodologia para a produção de material de valor agregado, como por exemplo, zeólita de elevada pureza, o qual possibilita inúmeras aplicações em diversos ramos de atividade. O objetivo deste trabalho foi otimizar a síntese de zeólita de elevada pureza do tipo Na-A a partir das cinzas volantes de carvão por meio da redução do tempo total do processo. A síntese foi realizada em duas etapas: a primeira consistiu na fusão alcalina das cinzas volantes e a segunda no tratamento hidrotérmico. Diferentes tempos de tratamento hidrotérmico foram testados até a obtenção de zeólita com elevado grau de pureza com uma redução de 4 h na segunda etapa da síntese. Os materiais sintetizados foram caracterizados pelas técnicas de difratometria de raios X e microscopia eletrônica de varredura. Os resultados de difração de raios X indicaram que os materiais sintetizados apresentaram fases cristalinas idênticas para a zeólita do tipo Na- A quando comparadas ao banco de dados. As microfotografias dos nanomateriais sintetizados apresentaram estruturas na forma cúbica, típicas desse tipo de material. Concluiu-se por meio do presente estudo que é possível reduzir o tempo total da síntese de duas etapas, enquanto é mantido o alto grau de pureza da zeólita Na-A produzida a partir das cinzas, sendo que dessa forma a obtenção desse material alternativo possa ser mais vantajosa do ponto de vista de economia de recursos.
Avaliação da remoção de elementos metálicos tóxicos presentes no efluente do aterro de cinzas de carvão mineral usando zeólita sintética
2017 - MIRANDA, CAIO da S.; IZIDORO, JULIANA de C.; GUILHEN, SABINE N.; FUNGARO, DENISE A.
A produção de energia elétrica usando carvão mineral gera diferentes tipos de resíduos que precisam ser dispostos adequadamente para não causar impactos ambientais significativos. Diversas técnicas têm sido adotadas para que haja a redução da lixiviação dos elementos metálicos tóxicos presentes nas cinzas. O preparo do aterro de cinzas usando camadas de calcário e argila foi usado como alternativa por uma usina termelétrica a carvão localizada na região sul do Brasil. A utilização das cinzas leves para a síntese de materiais de valor agregado, por outro lado, também pode amenizar esse problema pelo fato de reduzir a quantidade de resíduo a ser disposto. O objetivo do presente trabalho foi avaliar a remoção de elementos tóxicos presentes no efluente de um aterro de cinzas usando zeólitas sintetizadas a partir dos próprios resíduos de combustão do carvão. Os ensaios foram realizados em batelada empregando-se 10 g de zeólita/L e 20 g de zeólita/L. A comparação entre as concentrações dos elementos do efluente antes e após o contato com a zeólita, bem como as análises de pH e condutividade foram realizadas. Os resultados indicaram que cromo e arsênio foram os principais elementos tóxicos presentes no efluente do aterro de cinzas que apresentavam concentração acima do permitido pela legislação ambiental. Após o tratamento com a zeólita, a concentração de arsênio no efluente reduziu de 1,09 mg/L para 0,275 mg/L na dose de 10 g/L e ficou abaixo do limite de detecção do equipamento (< 0,01) na dose de 20 g/L. Para o cromo, não houve alteração da concentração, enquanto uma elevação dos valores de pH e condutividade do efluente foi observada. O presente estudo sugere que a zeólita de cinzas leves de carvão podem ser usadas como forma de tratamento de efluentes contendo elevados níveis de arsênio.