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Marys Lene Braga Almeidahttp://lattes.cnpq.br/6095221702693578Carmen Couto RibeiroEduardo Henrique Martins NunesEliane AyresMarcelo Libâniohttp://lattes.cnpq.br/4468896024083307Marcos Vinicius Vieira Pereira2023-10-18T17:28:47Z2023-10-18T17:28:47Z2023-06-27http://hdl.handle.net/1843/59616A pesquisa consistiu em produzir um material inovador por meio do uso da incorporação de cinza da casca de arroz (CCA) em uma matriz polimérica de poliuretano (PU) à base de reagentes de origem vegetal para verificar a remoção de óleo diesel por sorção e na resistência de propagação de chamas. O resíduo calcinado possui baixa área superficial específica 5,58 m2/g obtida por sorção de N2, 93,64% de sílica evidenciada pela fluorescência de raios X, com estrutura predominantemente amorfa mostrada por meio de difratometria de raios X, e registrou vibrações inerentes aos grupos funcionais siloxanos observadas por meio da espectroscopia de infravermelho por transformada de Fourier. A espuma de PU sintetizada e usada como matriz para receber as incorporações de resíduo de CCA apresentou um ângulo de contato de 119,35°, com morfologia evidenciada pela microtomografia de raios X apresentando diâmetros de poros entre 500-700 m, porosidade aberta maior que 96%, fator importante para a disponibilidade de sítios ativos nos compósitos. Foram sintetizados 3 tipos de compósitos com teores de 2%, 8% e 20% de CCA incorporadas ao PU. Os materiais apresentaram partículas do resíduo rico em sílica presentes na morfologia do polímero evidenciadas na miscroscopia eletrônica de varredura, aumento da espessura média das paredes da matriz de PU sem mudanças na porosidade aberta do complexo poroso constatada na microtomografia de raios X, melhora na hidrofobicidade do PU com ângulo de contato de 128,32°, além de aumento da estabilidade térmica de até 13% frente a perda de massa analisada na termogravimetria. Quanto à sorção em sistema monofásico de óleo diesel, os compósitos com os maiores teores de incorporação de CCA (8% e 20%) aumentaram significativamente a capacidade de remoção do hidrocarboneto em relação à espuma de PU, obtendo ganhos de até 43,4% na capacidade de sorção, os quais removeram 5348 mg.g−1 com o compósito de 8% de CCA e 5518 mg.g−1 com a espuma com 20% de CCA. Em sistemas bifásicos de água e óleo diesel variando a concentração de 10 até 150 g/L, há perspectiva de que o ângulo de contato dos compósitos tenha interferido nos desempenhos de sorção, sendo o compósito com 2% o que mais sorveu o hidrocarboneto. A cinética de sorção mostrou elevada taxa em tempos de contato inferiores a 8 minutos. Os modelos não-lineares de pseudossegunda ordem se ajustaram satisfatoriamente ao fenômeno de sorção observado com R2 de 0,90. Foi avaliado o potencial de retardância de chama constantando-se melhor resistência à propagação para o compósito com teor de 8% de CCA incorporada ao PU.The research consisted of producing an innovative material through the use of the incorporation of rice husk ash (RCA) in a polyurethane foam (PUF) polymeric matrix based on reagents of plant origin to verify the removal of diesel oil by sorption and in the flame propagation resistance. The calcined residue has a low specific surface area of 5.58 m2 /g obtained by adsorption of N2, 93.64% of silica evidenced by X-ray fluorescence, with a predominantly amorphous structure shown using X-ray diffraction, and recorded vibrations inherent to the siloxane functional groups observed by Fourier transform infrared spectroscopy. The PUF synthesized and used as a matrix to receive the incorporation of RHA residue showed a contact angle of 119.35°, with morphology evidenced by X ray microtomography showing pore diameters between 500-700 m, open porosity greater than 96%, an essential factor for the availability of active sites in composites. Three types of composites were synthesized with contents of 2%, 8%, and 20% of RHA incorporated into the PUF. The materials showed particles of residue rich in silica present in the polymer morphology evidenced in scanning electron microscopy, an increase in the average thickness of the walls of the PUF matrix without changes in the open porosity of the porous complex verified in the X-ray microtomography, improvement in the hydrophobicity of the PUF with a contact angle of 128.32°, in addition to an increase in thermal stability of up to 13% compared to the mass loss analyzed in thermogravimetry. As for the sorption in a single-phase diesel oil system, the composites with the highest levels of RHA incorporation (8% and 20%) significantly increased the hydrocarbon removal capacity to the PUF, obtaining gains of up to 43, 4% in sorption capacity, which removed 5348 mg.g−1 with the 8% RHA composite and 5518 mg.g−1 with the foam with 20% RHA. In biphasic systems of water and diesel oil varying the concentration from 10 to 150 g/L, there is a perspective that the contact angle of the composites has interfered with the sorption performances, being the composite with 2% the one that most absorbed the hydrocarbon. The sorption kinetics showed a high rate of contact times of less than 8 minutes. The pseudo-second-order non-linear models fit the observed sorption phenomenon satisfactorily with R2 of 0.90. The flame retardancy potential between one of the composites and the PUF was evaluated by establishing a better propagation resistance potential for the composite with an RHA content of 8%.porUniversidade Federal de Minas GeraisPrograma de Pós-Graduação em Construção CivilUFMGBrasilENG - DEPARTAMENTO DE ENGENHARIA MATERIAIS E DA CONSTRUÇÃO CIVILhttp://creativecommons.org/licenses/by-nc-nd/3.0/pt/info:eu-repo/semantics/openAccessConstrução civilMateriais de construçãoCompósitosCombustíveis dieselCalorArrozPolímerosCompósitos de poliuretanoCinza da casca de arrozSorçãoÓleo dieselResistência térmicaEspumas de poliuretano com cinzas de casca de arroz : análise da utilização na sorção de óleo diesel e como retardante de chamaPolyurethane foams with rice husk ash: analysis of their use in diesel oil sorption and as a flame retardantinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisreponame:Repositório Institucional da UFMGinstname:Universidade Federal de Minas Gerais (UFMG)instacron:UFMGCC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8811https://repositorio.ufmg.br/bitstream/1843/59616/2/license_rdfcfd6801dba008cb6adbd9838b81582abMD52ORIGINALMarcos Vinicius Vieira Pereira 2023.pdfMarcos Vinicius Vieira Pereira 2023.pdfapplication/pdf4955426https://repositorio.ufmg.br/bitstream/1843/59616/4/Marcos%20Vinicius%20Vieira%20Pereira%202023.pdfa610f3f0ac104bc6cb32d87227a06ddcMD54LICENSElicense.txtlicense.txttext/plain; charset=utf-82118https://repositorio.ufmg.br/bitstream/1843/59616/5/license.txtcda590c95a0b51b4d15f60c9642ca272MD551843/596162023-10-18 14:28:47.933oai:repositorio.ufmg.br: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ório InstitucionalPUBhttps://repositorio.ufmg.br/oaiopendoar:2023-10-18T17:28:47Repositório Institucional da UFMG - Universidade Federal de Minas Gerais (UFMG)false
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