https://repositorio.ufba.br/handle/ri/2617 2026-05-04T04:53:25Z https://repositorio.ufba.br/handle/ri/43753 Título: Estratégia sequencial de remediação de areia contaminada por petróleo usando microemulsões bio-baseadas Autor(es): Santos, Adriana Vieira dos Primeiro Orientador: Santos, Luiz Carlos Lobato dos Abstract: Oil spills in coastal zones cause persistent environmental impacts due to the deposition of hydrocarbons in soils and sediments, and the scientific literature still lacks remediation formulations that combine high efficiency with low environmental impact. Previous studies have demonstrated the effectiveness of anionic and nonionic surfactants in microemulsion systems; however, most of these formulations are based on petrochemical inputs, which are highly toxic and poorly biodegradable. To address this gap, this doctoral research aimed to develop, characterize, and apply environmentally friendly microemulsions formulated with plant-based components as sustainable cleaning agents for the ex situ remediation of beach sand contaminated with crude oil. The investigated system consisted of pine essential oil (oil phase), saponified coconut oil soap (anionic surfactant), isopropanol (cosurfactant), and water (aqueous phase). Pseudoternary phase diagrams were constructed to determine stability regions, and a full 2^3 factorial design was employed to evaluate the effects of the microemulsion volume-to- sand mass ratio, contact time, and sediment mass. Removal efficiency was quantified by UV– Vis spectroscopy and gas chromatography. The formulated cleaning agent exhibited physicochemical stability, low toxicity, and high biodegradability, as confirmed by the chemical safety data sheets of its components. Experimental results indicated oil removal efficiencies of up to 90% in batch tests, with superior performance for formulations containing 30–60% of the oil phase. An additional conceptual contribution was the proposal of a sequential remediation strategy based on micellar regeneration, in which the initial washing step with the microemulsion is followed by an aqueous rinse capable of remobilizing adsorbed surfactant molecules, promoting new in situ micellar self-assembly within the sediment. This approach achieved up to 96.5% oil removal in fixed-bed column experiments, with 96% volumetric recovery of the microemulsion and a favorable environmental profile according to green chemistry metrics. Overall, the results demonstrate that bio-based microemulsions are effective and sustainable alternatives for the remediation of petroleum-contaminated coastal environments, contributing to advances in green chemistry and emerging environmental applications. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Tese 2025-10-27T00:00:00Z https://repositorio.ufba.br/handle/ri/43196 Título: Congresso de geoquímica dos países de língua portuguesa Abstract: The 16th Congress of Geochemistry of Portuguese-speaking Countries (XVI CGPLP) will be held at the University of Aveiro from July 28 to August 2, 2024. This event is organized by the Department of Geosciences of the University of Aveiro, the Geochemistry Group of the Geological Society of Portugal, and the Brazilian Society of Geochemistry, with the support of the GeoBioTec Research Unit - Geobiosciences, Geotechnologies, and Geoengineering. With the theme "Contributions of Geochemistry for a Sustainable Future," the congress highlights the role of Geochemistry in achieving the UN Sustainable Development Goals, promoting interdisciplinarity and encompassing all areas of scientific knowledge. The congress brings together scientists from Portuguese-speaking countries to promote scientific exchange among geochemistry professionals. Researchers from Portugal, Brazil, Mozambique, Angola, the USA, Morocco, and Algeria will participate in this event. The activities of the XVI CGPLP include 6 plenary conferences scientific sessions with presentations of communications and posters, workshops, and field trips, in addition to a sociocultural program. The scientific program is organized into the following thematic areas: T1: Geochemistry of magmatic, metamorphic, sedimentary, and hydrothermal processes; T2: Mineral and energy resources and innovative applications for a sustainable future; T3: Geochemistry: society, environment, and health; T4: (Bio)geochemical processes and cycles in the terrestrial critical zone; T5: Geochemical processes in the oceans, atmosphere, and climate change; T6: Analytical, geostatistical, and geochronological methods. Aveiro, known as the “Venice of Portugal,” is this year the Portuguese Capital of Culture. Under the motto “The year as a stage. An infinite scenery,” Aveiro 2024 aims to affirm the city as a cultural and artistic center, offering an intense schedule of activities that will also enrich the congress program. Editora / Evento / Instituição: Universidade de Aveiro Tipo: Livro 2024-01-01T00:00:00Z https://repositorio.ufba.br/handle/ri/43146 Título: Fotodegradação de microplásticos em sedimentos de manguezais e praias na Baía de Todos os Santos, Bahia – Brasil. Autor(es): Souza, Claudineia de Souza Primeiro Orientador: Celino, Joil José Abstract: The growing concern with microplastic (MP) pollution in coastal and estuarine ecosystems has driven advances in environmental geosciences, particularly in understanding their transport, accumulation, and degradation dynamics. Within this context, the thesis entitled “Photodegradation of Microplastics in Mangrove and Beach Sediments in Todos os Santos Bay, Bahia – Brazil”, developed by Claudinéia de Souza Souza in the Graduate Program in Geochemistry: Petroleum and Environment (POSPETRO/UFBA), under the supervision of Prof. Dr. Joil José Celino and co-supervision of Prof. Dr. Márcio de Jesus Silva, investigates the mechanisms of MP degradation in contrasting sedimentary environments of Todos os Santos Bay (TSB), one of the largest tropical estuaries in Brazil and subject to intense anthropogenic pressures. The research is structured into three complementary chapters. The first analyzes the spatial distribution and potential sources of MPs in beach and mangrove sediments of TSB, considering abundance, morphology, color, and elemental composition. The results reveal significant differences between the ecosystems, associated with factors such as grain size, organic matter content, and hydrodynamics. In the second chapter, a multivariate statistical analysis integrates physicochemical sediment parameters (pH, total organic carbon, and total nitrogen) with MP behavior, allowing for discussion of their environmental persistence, interactions with the sediment matrix, and potential ecotoxicological implications. The third chapter constitutes the innovative axis of the thesis: the experimental assessment of photodegradation processes (photolysis and heterogeneous photocatalysis with TiO₂) applied to cosmetic plastic microspheres. Through gravimetric, spectroscopic (FTIR), and morphological (SEM/EDS) analyses, the feasibility and limitations of these degradation strategies are demonstrated, as well as their possible applications in remediation technologies. By integrating field data, geochemical analyses, and laboratory experiments, this work makes a substantive contribution to advancing environmental geochemistry in the study of plastic pollution, providing scientific support for public policies, technological development, and conservation of tropical coastal ecosystems. In addition to providing unprecedented data on TSB, the research expands the understanding of MP degradation processes, establishing itself as a reference for future investigations in Brazil and other tropical estuaries. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Tese 2025-05-20T00:00:00Z https://repositorio.ufba.br/handle/ri/42870 Título: Hidrocarbonetos policíclicos aromáticos, metais e foraminíferos em um estuário tropical: o caso do rio Serinhaém após um derrame de petróleo. Autor(es): Carneiro, Luanna Maia Primeiro Orientador: Hadlich, Gisele Mara Abstract: Monitoring of areas impacted by various activities can be carried out through the analysis of chemical elements and hydrocarbons in sediments, given the capacity of this matrix to preserve continuous records of environmental changes. In addition, biomonitors are used to assess the environment. In 2019, the Brazilian coast was hit by an oil spill that resulted in significant environmental and socioeconomic impacts. The oil reached the estuary of the Serinhaém River, located in the Baixo Sul region of the State of Bahia. This tropical environment is part of the Pratigi Environmental Protection Area (APA) and is an area that is a little influenced by anthropogenic activities. The present research aimed to investigate the environmental condition of the Serinhaém River estuary after the oil spill that hit the Brazilian coast in 2019. Sediments were collected at 14 sampling points, of which five were sediment cores, and nine were surface sediments. Polycyclic aromatic hydrocarbons (PAHs) and metals (Al, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn; semi-metallic As) were determined in the sediments. Granulometry, pH, total organic carbon (TOC), and total nitrogen (TN) analyses were also performed. Foraminifera were used as biomonitors because changes in the shells record environmental changes. For the 16 PAHs considered priority control pollutants, the maximum values in the surface sediments of ΣBHPAs (low molecular weight PAHs), ΣAHPAs (high molecular weight PAHs), and Σ16HPAs (sum of the 16 PAHs) were, respectively, 120.92, 152.56 and 273.48 ng g-1. Diagnostic ratios indicated the petrogenic origin of PAHs at points in the downstream part of the estuary. When comparing the PAH values, only the phenanthrene concentration (89.47 ng g-1) is above the TEL (Threshold Effect Level) at a point located in the middle estuary. Regarding the sedimentary cores, T3 (middle estuary) was the one that presented the highest Ω16PAHs (1508 ng g-1). A more significant presence of high molecular mass PAHs was observed, which was associated with a pyrogenic origin. The analyses of the diagnostic ratios showed that in T1, located near the city of Ituberá, no source of petrogenic origin was found. In T5, located downstream of the estuary, the BMM/AMM ratio indicates a petrogenic origin. For foraminifera, data from samples from 2022 were compared with samples collected in 2013, and an association was found between diversity and distribution along the estuary with physicochemical variables. In 2013 and 2022, the distribution of foraminifera was unrelated to the presence of chemical elements in the estuary. The concentrations of chemical elements did not differ between 2013 and 2022. Therefore, the area of the Serinhaém River estuary in the Pratigi APA, even after the 2019 oil spill, is preserved in terms of the concentrations of the analyzed chemical elements. As for the PAHs, there is an indication of petrogenic origin both in the core further downstream of the estuary and in the surface sediments of the downstream and middle estuary, indicating oil contamination from the downstream part of the estuary, which may be related to the 2019 spill. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Tese 2024-12-20T00:00:00Z