JULIANA DE CARVALHO IZIDORO

JULIANA DE CARVALHO IZIDORO

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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).
The flue gas desulfurization gypsum applications in production of eco-friendly cementitious matrices
2023 - BIBIANO, R.H.N.; IZIDORO, JULIANA de C.; FUNGARO, DENISE A.
Portland cement is one of the most manufactured materials in the world. The worldwide cement industry accounts for at least 5-8% of the anthropogenic CO2 emissions and therefore is an important sector for CO2-emission mitigation strategies to limit global warming. One of the strategies for reducing the carbon footprint of the cement industry is replace traditional Portland cement with other solid wastes. In the present study, the influence of the application of flue gas desulfurization gypsum (FGD gypsum) generated from coal-fired power plant in construction mortar was investigated. Cylindrical specimens were molded with Portland cement type CPII-F 32, sand and 0%, 25%, 50% and 75% amounts of FGD gypsum. After curing time of 1, 3, 7, 28 and 91 days, the cementitious materials were characterized mechanically by axial compressive strength, setting time and slump. The pastes in the age of 28 days were further characterized by X-ray diffraction with Rietveld analysis. Results showed that FGD gypsum can be used as a substitute for cement as a setting retarder in an amount of up to 25%, and as an accelerator in an amount of 75%, being necessary dosage of the specific traces of the materials depending on the purpose of its use.
Remoção de césio-137 em efluentes por adsorção em zeólita A sintetizadas a partir das cinzas do bagaço de cana-de-açúcar
2023 - ARAUJO, M.S.; COSTA E SILVA, D.L.; IZIDORO, J.; MELLO-CASTANHO, S.; FUNGARO, D.A.
Em decorrência do uso crescente de tecnologias com atividade nuclear, está a geração de rejeitos contaminados, em particular, os efluentes os quais representam grandes volumes de água contendo radionuclídeos ainda ativos em dispersão. Dentre os radionuclídeos gerados, o césio-137 (137Cs) está entre os mais preocupantes pelo fato de ser um emissor de raios gama e, ser também, um dos isótopos mais abundantes nos rejeitos radioativos da atividade nuclear e possuir meia-vida relativamente longa (30,4 anos). Atualmente, a adsorção é um dos métodos mais atraentes para a retenção de 137Cs em termos do bom desempenho de remoção de maneira segura. Vários materiais adsorventes inorgânicos têm sido amplamente utilizados, tendo destaque as zeólitas, que devido ao seu alto grau de cristalinidade, garantem maior seletividade e eficiência na adsorção em comparação a outros materiais como alumina, sílica gel e carvão ativo. Ainda, a possibilidade de ser sintetizada a partir de resíduos como as cinzas de bagaço de cana-de-açúcar, a torna um material de baixo custo. Desta forma, a presente pesquisa foi conduzida por meio do estudo da adsorção de uma solução de cloreto de césio por zeólita A sintetizada a partir das cinzas do bagaço de cana-de-açúcar e do impacto dos íons de Cs+ adsorvidos em sua estrutura cristalina. As amostras foram caracterizadas por diferentes técnicas a fim de avaliar sua composição química, tamanho de partícula, estrutura cristalina e comportamento térmico. Os resultados indicam a obtenção de zeólita tipo NaA de alta pureza e com elevada capacidade de adsorção. Ainda, o teor de sódio presente na zeólita foi completamente substituído pela troca iônica de íons de Na+ por íons de Cs+. Portanto, o material sintetizado é uma solução promissora para o tratamento e remoção de césio-137 em efluentes gerados contaminados.
Circular economy in the sugarcane agroindustry
2022 - FUNGARO, DENISE A.; IZIDORO, JULIANA de C.
The sugarcane industry in the process of producing sugar and ethanol generates bagasse in large amounts. The burning of bagasse used for steam and electricity generation produces 3 million tonnes of bagasse fly ash (BFA) annually. Handling and improper disposal of BFA cause pollution in soils, air, and water, which results in environmental challenges and human health problems. The valorization of BFA is a convenient and sustainable means to reduce solid waste generation and decrease the environmental pollution load. The purpose of this research is to investigate the application of BFA for the synthesis of zeolite. Because of three-dimensional structure and unique porous properties, zeolite is a value-added product with many applications such as adsorbent material and industrial catalysis. After separation of the coarser particles containing mainly unburned carbon, fine particles of BFA were used to synthesize zeolite by alkali fusion (550 oC; 1 h; BFA: NaOH= 1:1.2 w/w) followed by hydrothermal treatment at 100 °C for 3 h. Si/Al molar ratio of 1.0 was adjusted with an external alumina source. BFA and synthesized zeolite were characterized using XFR, XRD, and MEV. The results showed that BFA may be used effectively for the synthesis of zeolite NaA with high purity comparable with the commercial product. Zeolite NaA is employed in sugarcane mills in the dehydration processes for the removal of water from the hydrated ethanol. Thus, the application of BFA in zeolitization process strategy provides not only environmental and economic benefits for the sugarcane agroindustry but also contributes to a circular economy and towards the achievement of Sustainable Development Goal 12.
Avaliação dos níveis de radioatividade natural produzidos na atividade carbonífera e em amostra de clínker
2022 - FUNGARO, DENISE A.; SILVA, PAULO S.C.; IZIDORO, JULIANA C.; GROSCHE, LUCAS C.; BIBIANO, RAMIRO H.N.
Os Produtos de Combustão de Carvão são materiais produzidos em usinas termelétricas que contêm radionuclídeos de ocorrência natural derivados da matriz de carvão, enriquecidos em até uma ordem de magnitude em relação aos níveis originais. A avaliação do impacto radiológico dos ambientes circundantes das usinas termelétricas é de fundamental importância para monitorar os níveis de radiação, a qual as pessoas estão expostas direta ou indiretamente, visto que níveis aceitáveis podem ser ultrapassados com essas atividades. A análise de ativação de nêutrons foi usada para determinar 238U e 232Th e a espectrometria de raios gama para determinar os conteúdos de 226Ra, 228Ra, 210Pb e 40K presentes no carvão, nas cinzas sílico-aluminosas, nos materiais zeolíticos sintetizados a partir de cinzas e em amostras de solo coletadas nas proximidades de Usina termelétrica de Figueira, localizada no Paraná. As concentrações de atividade foram comparadas com a média mundial das diferentes amostras. A análise de ativação de nêutrons também foi utilizada para avaliar os riscos radiológicos decorrentes da presença de cinzas sulfatadas e clínquer em materiais de construção. As cinzas sulfatadas podem substituir o gesso natural em matrizes cimentícias.
Brine sludge waste from a Chlor-alkali industry: characterization and its application for non-structural and structural construction materials
2021 - IZIDORO, JULIANA de C.; FUNGARO, DENISE A.; VIVIANI, LUCIANA C.; SILVA, ROGERIO da C.
Brine sludge (BS) is an industrial waste generated in large amounts by the Chlor-alkali industry and, usually disposed into industrial landfills. Because BS contains several chemical compounds, also presents a potential environmental impact. The feasibility of the utilization of brine sludge wastes for the preparation of value-added materials was investigated. The characterization of two brine sludge samples was performed in terms of chemical and physical composition, particle size distribution, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and thermal analysis (DTA/TG). Elements like Ca, Si, Na, Mg, Al, Cl, and Fe were identified in the samples. The XRD results confirmed the crystalline nature of compounds and indicated that the main compounds in brine sludge samples were calcium carbonate, sodium chloride, magnesium hydroxide, and quartz. FTIR showed the presence of varying functional groups like carbonate, siloxane, and hydroxide. The two brine sludge samples can be considered as a fine powder with the mean diameter (d50) of 4.984 µm and 24.574 µm, for the BS from Santo André and Cubatão, respectively. The results indicated that the brine sludge samples presented favorable characteristics to use limestone ?ller and binder alternative to Portland cement in the nonstructural construction materials. The incorporation of brine sludge in geopolymeric materials is another possible use in sustainable construction material products. The production of value-added products from brine sludge will be an important contribution towards sustainable development adopted by the Chlor-alkali industry.
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.
Column leaching test for the evaluation of immobilization of toxic elements in modified coal fly ash
2019 - IZIDORO, JULIANA; FUNGARO, DENISE; CAMPELLO, FELIPE; GUILHEN, SABINE
Gestão de resíduos sólidos agroindustriais e obtenção de produtos de valor agregado
2020 - IZIDORO, JULIANA de C.; BIBIANO, RAMIRO H. das N.; LIMA, DANIELE de A.V.; FUNGARO, DENISE A.
As atividades da agroindústria estão gerando grandes quantidades de resíduos devido aos processos produtivos e alto padrão de consumo da sociedade. A maioria desses resíduos é descartada por queima, despejo ou aterramento causando impactos ambientais e na saúde humana. O conceito de aproveitamento de resíduos como componente da economia circular é uma alternativa para a disposição inadequada. A valorização de resíduos envolve a determinação das características físico-químicas por diferentes técnicas (FRX, DRX, MEV, etc). A etapa posterior consiste na aplicação de processos que transformam o resíduo em material de valor agregado. As cinzas provenientes da queima do bagaço da cana-de-açúcar são um dos principais resíduos gerados no Brasil. O alto teor de sílica possibilita a obtenção de silicato de sódio, nanosílica e zeólita. Esses produtos foram aplicados como material adsorvente e na produção de filmes biodegradáveis de amido. Resíduos lignocelulósicos (serragem, endocarpo de Macaúba) foram convertidos em biocarvão. As suas principais aplicações são como adsorvente e precursor de carvão ativado, além de apresentar potencial para o melhoramento das características ambientais de telhado verde. Dentre os resíduos inorgânicos, os produtos da combustão de carvão, compostos por sílica e alumina, são matéria-prima para obtenção de nanomateriais adsorventes como zeólita de alta pureza e tobermorita. Da mesma forma, o resíduo da reciclagem de alumínio pode ser usado na síntese de zeólita. A composição das cinzas sulfatadas geradas no processo úmido de dessulfurização indica seu potencial como aditivo no cimento e na formação de geopolímeros. Nessa abordagem, a adoção da economia circular na gestão de resíduos contribui significativamente para o cumprimento dos Objetivos de Desenvolvimento Sustentável (ODSs), especificamente, ODS 12: “Até 2030, reduzir substancialmente a geração de resíduos por meio da prevenção, redução, reciclagem e reuso”.
Synthesis of calcium silicate hydrate compounds from wet flue gas desulfurization (FGD) waste
2020 - FUNGARO, DENISE A.; GROSCHE, LUCAS; IZIDORO, JULIANA de C.
In this study Calcium silicate hydrate based products (CSHP) were synthesized from wet flue gas desulfurization waste (FGD) by alkali fusion followed by hydrothermal treatment. The effect of various factors on the formation of products, such as mineralizing agent, fusion temperature and time, crystallization time and addition of Ca and Si were studied as well as the conditions optimized. The FGD and synthesized materials were characterized by using X-Ray (XRD), Scanning Electron Microscope (SEM), X-ray fluorescence (XFR), among other methods. A fusion temperature of 600 °C with NaOH, fusion duration of 1 h, and a subsequent hydrothermal temperature of 100 °C for a reaction of 24 h were found to be the optimal conditions. In these synthesis conditions, CSHP containing tobermorite and Al-tobermorite was the major phases. The synthesized CSHP revealed high selective uptake for Cs+ in water. The maximum adsorption capacity of Cs+ onto the synthesized material, as calculated from the Langmuir model, was 1949 µmol g-1. The performance on the Cs+ removal in the presence of high Na+ contents was also evaluated. The adsorbent material showed a high Cs+ adsorption capacity in deionized water and a decrease of 56% and 62% in saturated media with the Na+ ions and seawater, respectively. Therefore, CSHP as a higher value-added product can be obtained from a by-product of a coal-fired power plant, which has wide range applications, including for Cs+ removal from wastewater.