Engenharia Química

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http://repositorio.ufes.br/handle/10/17472
Programa de Pós-Graduação em Engenharia Química

Centro: CCAE
Telefone: (28) 3552 8719
URL do programa: http://www.engenhariaquimica.alegre.ufes.br/pos-graduacao/PPEQ

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Navegando Engenharia Química por Autor "Altoé, Mario Alberto Simonato"

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    Síntese do biodiesel de óleo de soja utilizando óxido de cálcio oriundo da concha de sururu impregnado com íon itérbio (3+)
    (Universidade Federal do Espírito Santo, 2024-07-25) Gomes, Mirian Alves; Guimarães, Damaris; https://orcid.org/0000-0002-4932-3252; http://lattes.cnpq.br/6576377621734943; Barañano, Audrei Giménez; https://orcid.org/0000-0002-0174-5202; http://lattes.cnpq.br/6155024776819193; https://orcid.org/0009-0004-4358-8673; http://lattes.cnpq.br/7254607078386975 ; Altoé, Mario Alberto Simonato; https://orcid.org/0009-0004-6226-7912; http://lattes.cnpq.br/8481776828705621 ; Souza, Murilo de Oliveira; https://orcid.org/0000-0002-5299-564X; http://lattes.cnpq.br/1832643912229312
    The synthesis of biodiesel is carried out through transesterification reaction, using vegetable oils or animal fats, short-chain alcohols, in the presence of basic/acid catalysts, whether heterogeneous or homogeneous. Among heterogeneous catalysts, calcium oxide (CaO) shows promising results. In this study, calcium oxide obtained from sururu shell was impregnated with Yb3+ ions, via coprecipitation method. The catalysts were thermally activated by calcination at 900°C for 4 hours and evaluated for their catalytic potential in methyl biodiesel synthesis using soybean oil. Thermogravimetric analysis (TGA), X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) were conducted to obtain catalyst characteristics and properties. Biodiesel yield was determined by proton nuclear magnetic resonance (1H NMR) and thin-layer chromatography (TLC). Central composite rotational design (CCRD) was employed to optimize reaction conditions. Results revealed that maximum efficiency was achieved at 80°C, with 5% catalyst and alcohol:oil ratio of 15:1, resulting in 87% conversion for CaO without Yb3+ and 85% for CaO with Yb3+, within just 1 hour. Modified CaO allowed for five cycles of biodiesel synthesis, with a 2.78% reduction in yield in the first catalytic cycle. Conversely, CaO without Yb3+ showed a significantly greater yield reduction, totaling 30.48%. The feasibility of reuse across multiple cycles was attributed to the robustness promoted by oxide impregnation, due to the low solubility of calcium oxide.
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    Síntese, caracterização e aplicação de um compósito de quitosana e HDL (Mg/Al/CO3) na adsorção de fosfato
    (Universidade Federal do Espírito Santo, 2021-08-27) Ribeiro, Nathália Isidoro; Guimarães, Damaris; https://orcid.org/0000000249323252; http://lattes.cnpq.br/6576377621734943; https://orcid.org/0000-0002-4672-2346; http://lattes.cnpq.br/4390218602944365; Altoé, Mario Alberto Simonato; https://orcid.org/0009-0004-6226-7912; http://lattes.cnpq.br/8481776828705621; Oliveira, Michel Picanço; https://orcid.org/0000000192410194; http://lattes.cnpq.br/6383844066460475
    In the present work, the phosphate adsorption was studied using a composite formed by Layered Double Hydroxide (LDH) type Mg6Al2(CO3)(OH)16.4H2O and chitosan. For this, the composite was synthesized by the co-precipitation method of its constituents and applied in the phosphate adsorption, and its performance was compared to the adsorption performance of the same anion of chitosan and LDH individually. All adsorbents were characterized before and after adsorption tests by Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy (SEM-EDS), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Adsorption of nitrogen (BET). According to the characterization, the adsorbents were successfully synthesized and their structure did not change after being used in phosphate adsorption. It suggests that the anion adsorption occurred by electrostatic interaction with the surface of the studied materials. According to the adsorption kinetic study, it was observed that the removal (57.2%, starting from the initial concentration of 63.3 mg/L, at 25°C±1) and the loading (120.8 mg/g) presented by the composite were greater than twice those presented by LDH (21.6% and 54.9 mg/g) and chitosan (20.7% and 45.2 mg/g) individually, under similar experimental conditions. The Pseudo-first Order, Pseudo-second Order, Elovich and Intraparticle Diffusion models were fitted to the data and the best fits were obtained by the Pseudo-second Order model for LDH (R2 = 0.98) and the composite LDH/Chitosan (R2 = 0.98) and PseudoFirst Order for chitosan (R2 = 0.96). For the equilibrium study, the Langmuir, Freundlich and Temkin models were used, with the Freundlich model being the one that best fit the experimental data (R2 = 0.98). These results show that there was an interaction between the constituents of the LDH/Chitosan composite that enhanced its phosphate adsorption capacity, allowing it to be effectively applied for this purpose. Keywords: hydrotalcite, phosphate removal, wastewater treatment.