http://www.bdtd.uerj.br/handle/1/3709 2026-10-12T11:52:29Z 2026-10-12T11:52:29Z Cruz, Monick Alves da http://www.bdtd.uerj.br/handle/1/26027 2026-08-21T12:57:46Z 2016-03-08T00:00:00Z

Título: Avaliação da biodegradabilidade de polímeros comerciais pelo método do ambiente marinho simulado Autor: Cruz, Monick Alves da Primeiro orientador: Leite, Márcia Christina Amorim Moreira Abstract: The use of biodegradable polymers is an alternative form to decrease the deposited amount of polymer materials in landfills and body of water, by minimizing the impact of these materials on the environment. Different methods to estimate biodegradation rate of a polymer have been used, such as: simulated soil and CO2 dosage. In this work, a methodology for analyze commercial polymers biodegradation mechanism in the marine environment will be developed. This methodology purposes immersing the polymers in two different systems: two aquariums containing natural and synthetic seawaters and the third. It was possible to consolidate a methodology for polymers biodegradability investigation in marine environment and to create a degradation profile of the polymers used. Instituição: Universidade do Estado do Rio de Janeiro Tipo do documento: Dissertação

2016-03-08T00:00:00Z Pereira, Carolina Acioli http://www.bdtd.uerj.br/handle/1/26021 2026-08-20T16:59:11Z 2007-06-06T00:00:00Z

Título: Remediação de latossolos brasileiros contaminados com óleo diesel via oxidação química por reagente de Fenton Autor: Pereira, Carolina Acioli Primeiro orientador: Calderari, Mônica Regina da Costa Marques Abstract: The natural presence of iron in Brazilian latosoils was studied to evaluation the remediation efficiency of soils contaminated with hydrocarbons by the advanced oxidative process using the Fenton reagent. It was developed a study in different soils types (yellow latosoils-LA and red latosoils-LV) with different iron contents, contaminated with diesel oil. For the remediation tests it was used a soil previously contaminated with 500 mg.g-1 of diesel oil. In order to evaluate the limits conditions of the system, the following parameters were tested: hydrogen peroxide concentration, of iron (II) salt concentration and contact time. All the hexanic extracts were analyzed quanti and qualitatively by high resolution gas chromatography after the Soxhlet extraction. The results indicated a high remediation (greater than 80%) despite the soil used, but the yellow latosoils kinetic (low iron content) was superior than the real one (high iron content). Instituição: Universidade do Estado do Rio de Janeiro Tipo do documento: Dissertação

2007-06-06T00:00:00Z Souza, Franciele Pereira de http://www.bdtd.uerj.br/handle/1/25781 2026-07-27T12:58:42Z 2026-03-27T00:00:00Z

Título: Desenvolvimento de metodologia para isolamento e caracterização de microplásticos em iogurtes Autor: Souza, Franciele Pereira de Primeiro orientador: Costa, Marcos Antônio da Silva Abstract: Microplastics (MPs) are polymeric particles smaller than 5 mm that, due to their high production and small size, are easily dispersed in the environment. As a consequence, they are found in foods such as honey and milk, and in the human body, such as in blood and even breast milk. This study aimed to develop a method to investigate the presence of microplastics in yogurts. The samples were obtained from commercially available yogurts of different brands and flavors, including strawberry, natural, natural skimmed, and Greek yogurt, with polypropylene and polystyrene packaging. The standard samples underwent a digestion test to find the best methodology for digesting and isolating the microplastics. Optimization of the sample isolation process with 10% (w/v) KOH indicated optimal conditions of 1.0 g of sample, with a KOH volume of 100 mL, and a digestion time of 24 h, resulting in efficiencies consistently above 99%. Recovery tests validated the methodology, showing high rates for PS1 (93.00±2.20%), PS2 (97.00±2.01%), PP1 (93.20±4.03%), and PP2 (97.06±4.20%). The best methodology found was applied to the samples and analyzed with optical microscopy to visualize the particles in the filter, and then analyzed by Fourier transform infrared microspectrometry (μ-FTIR). The method developed in this research was able to detect and identify the microplastics present in commercial yogurt samples and contribute to other studies in the area, providing more information about a new problem and potentially contributing to future research. Instituição: Universidade do Estado do Rio de Janeiro Tipo do documento: Dissertação

2026-03-27T00:00:00Z Silva, João Victor Viana da http://www.bdtd.uerj.br/handle/1/25757 2026-07-15T13:18:37Z 2025-02-19T00:00:00Z

Título: Síntese e caracterização de compósitos de redes metalorgânicas de Cério com TiO2 para remediação de águas por fotocatálise Autor: Silva, João Victor Viana da Primeiro orientador: Gonçalves, Marcos Vinicius Colaço Abstract: Metal-organic frameworks (MOFs) are a relevant class of materials which gained prominence during the last 20 years. The flexible design of their electronic, molecular and crystalline properties branched in heterogeneous photocatalysis, one of the most sustainable methods for water remediation. Heterogeneous photocatalysis is considered one of the most sustainable and efficient alternatives for the degradation of organic micropollutants on aqueous media. Among the different archetypes, UiO-66 possesses interesting properties such as chemical stability and high surface area. Ce-UiO-66 is able to utilize a wider range of solar radiation spectrum and favorable electronic properties for photooxidation, spontaneous redox pair and besides structural matters into the Ce-MOFs synthesis. A typical material, TiO2 presents high oxidative potential but known limitations such as necessity of ultraviolet solar radiation and low specific surface area. The combination of both materials enhances the capability of removing pollutants by the design of composites in a heterojunction. This work proposes the synthesis of new materials based on Ce-UiO-66 and TiO2 for the photocatalysis of the model pollutant methylene blue. MOFs obtained in longer synthesis duration presented more pronounced adsorption and photocatalytic removal, mainly the 4-hour MOF which presented a second Ce(III) phase. Composites with lower TiO2 loading exhibited enhanced pollutant removal altogether with interesting features: 21 nm particle diameter revealed by Transmission Electron Microscopy, the presence of Ce(III)/Ce(IV) pair is suggested by X-Ray Absorption Spectroscopy. Instituição: Universidade do Estado do Rio de Janeiro Tipo do documento: Dissertação

2025-02-19T00:00:00Z