Engenharia de Materiais (UACSA)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/2913
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APP - Artigo Publicado em Periódico
TAE - Trabalho Apresentado em Evento
TCC - Trabalho de Conclusão de Curso
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9 resultados
Resultados da Pesquisa
Item Aplicação de nanomateriais advindos de biomassa para tratamento de águas residuárias da indústria têxtil(2019-01-25) Nascimento, Rizia Keila do; Araújo, Ana Cláudia Vaz de; http://lattes.cnpq.br/6861890992609511; http://lattes.cnpq.br/8972131109377770The inadequate disposal of industrial effluents has caused serious problems of environmental contamination worldwide. In the textile pole of Pernambuco some cases of river pollution were reported due to the process of dyeing and washing of fabrics. In this work, the feasibility of the use of nanostructured carbonaceous materials (CN) in the adsorption of textile dyes is studied. To obtain the carbonaceous material sugarcane leaves were used, these were washed, dried, crushed and submitted to hydrothermal synthesis. The samples were characterized by X-ray diffractometry (XRD), infrared (IR) spectroscopy, thermogravimetric analysis (TGA) and porosimetric analysis. The synthesized materials were presented as finely divided dark powders. In adsorption analyzes of the indigo carmine and red congo dyes the nanomaterials showed to be promising adsorbents. It was possible to observe a favorable behavior in relation to the adsorption of the dyes in liquid medium. The Langmuir, Freundlich and Redlich- Peterson isotherm models were suitable for the studied materials. The kinetic adsorption analysis suggests a pseudo second order behavior. The adsorptive mechanism of the nanomaterials could be characterized as heterogeneous, with adsorbate / adsorbent interactions of a chemical nature, where adsorption in monolayers is carried out at low concentrations and in multilayers at high concentrations of dye.Item Análise do processo adsortivo de corantes industriais por nanopartículas magnéticas de magnetita (Fe3O4)(2019-07-08) Cabral, Ariane Nathália de Siqueira Souza; Araújo, Ana Cláudia Vaz de; http://lattes.cnpq.br/6861890992609511; http://lattes.cnpq.br/3246406733304902Environmental degradation is an inevitable factor that accompanies the development of the population and unfortunately this has reached water systems, rivers and water sources. Among the agents that contribute to the contamination and degradation are the dyes from the textile and food industries that are discarded throughout the production processes. There are several methods being developed to eliminate the effluent dyes in rivers and springs, among which is the adsorption process. The magnetic nanoparticles of magnetite (Fe3O4) have been previously tested in the adsorption of dye residues from the textile and food industries. In this context, the objective of this work was to study the efficiency of magnetic nanoparticles of magnetite (NPs) in the adsorption process of some dyes present in industrial textile effluents, such as dyes, methyl orange (MEL) and methylene blue (AM) . A factorial design 2³ was established obtaining as factors studied time, pH and temperature, and for these factors its levels were analyzed. Analyzes were made for systems under ultrasound and under magnetic stirring, and for this, significant results were obtained for the two dyes. According to the results obtained for the ALM / NPs, factors such as time and pH with greater significance. It was observed that the most successful tests for adsorption were the tests 02 (11,362) and 06 (10,057), for the systems under ultrasound and under magnetic stirring, respectively. For the AM / NPs it was significant only the factor, time. The most favorable tests for the dye adsorption system were 04 (19,144) and 06 (21,457), for systems under ultrasound and under magnetic stirring, respectively.Item Produção de nanopartículas magnéticas aplicada ao processo de tratamento de efluentes oriundos das indústrias têxteis(2018-08-27) Damasceno, Bárbara Souza; Araújo, Ana Cláudia Vaz de; http://lattes.cnpq.br/6861890992609511; http://lattes.cnpq.br/6533105269743189Iron oxide magnetic nanoparticles (NPs) were synthetized by chemical coprecipitation method under ultrasound. Synthetized NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, porosimetry and magnetometry. The crystalline phase of the obtained NPs was identified as maghemite and the crystallite average size was estimated by Scherrer equation around 31.5 nm. The FTIR spectra presented distinct absorptions bands at corresponding to intrinsic stretching vibrations of Fe–O bond at the iron oxides. Langmuir and BET surface areas of as-formed samples is 220,15 ± 19,81 m2 g-1 and 127,19 ± 4,94 m2 g-1 respectively. NPs samples present ferromagnetic behavior and saturation magnetization (SM) value of 46 emu g-1. Adsorption performances on synthetized and commercial nanoparticles were investigated and compared. The influences of parameters including pH, dye concentration, and agitation time have been investigated in order to find the optimum adsorption conditions. Parameters as pH 4.0, with 150 min of contact time and dye concentration of 20 mg L-1 were chosen. Adsorption results indicate that the isotherm and kinetics for dye adsorption on NPs obey Freundlich isotherm and pseudo-second-order kinetic, respectively. The maximum dye (20 mg·L-1) removal efficiency to maghemite NPs was found to be 43% and to commercial magnetite NPs was 33%. For the same experimental conditions, maghemite also had better application of the available area for adsorption than the magnetite NPs, presenting values of 8.80 mg g-1 and 6.12 mg g-1, respectively.Item Síntese e caracterização de um nanocompósito de grafite magnético para adsorção dos corantes Reactive Black 5 (RB5) e Azul de Metileno (AM)(2019-12-13) Damasceno, Bárbara Souza; Araújo, Ana Cláudia Vaz de; http://lattes.cnpq.br/6861890992609511; http://lattes.cnpq.br/6533105269743189Magnetic graphite nanocomposite (NGM) based on magnetic nanoparticles (NPs) and graphite nanoplatelets has been synthesized by a novel hydrothermal synthesis route. NGM and its precursors were characterized by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). The nanomaterial discoloration efficiency (%Ads) using reactive black 5 (RB5) and methylene blue (AM) textile dyes in aqueous solution as target pollutant were evaluated. The influence of adsorptive parameters on effluent discoloration efficiency responses was evaluated from a 23 factorial design and the response surface analysis of central rotational composite design. Adsorption parameters evaluated include: adsorbent mass, adsorbate concentration and agitation speed. It was observed that the parameters agitation speed (rpm) and concentration of adsorbate (mg L-1) are the factors more significant than any other combination and it is highly indicated that they should be parameterized in combination. NGM statistical results showed %Ads ~98% in the RB5 removal, extremely high adsorption velocity, since it reached the adsorption equilibrium within 10 minutes of contact with the adsorbate and it presented 99% adjustment for pseudo first and second order kinetics, besides it presented a maximum adsorptive capacity of ~93 mg g-1 for the adjustment of Langmuir model, predominant in this system. The %Ads of AM onto NPs and graphite was ~59% and 100%, respectively. The study shows that NGM can be magnetically separated from the aqueous solution without introduce any byproduct during adsorption and presented favorable adsorptive properties, which makes evident its applicability of use as environmental remediator. The application of this synthetic rout becomes of technological interest when, besides being unprecedented and low cost, NGM adsorptive properties are attractive to effectively discolor wastewater.Item Caracterização de matérias-primas cerâmicas utilizadas na produção de placas de revestimento em indústria do Cabo de Santo Agostinho(2019-12-10) Silva, Renata Arcelino da; Diniz, Verônica Cristhina de Souza; http://lattes.cnpq.br/9239037374332331; http://lattes.cnpq.br/4639841941851252Properties of ceramic products are related to initial characteristics of raw materials, so it is important to study them to obtain a quality product. In this study, aimed to evaluate clay composition and study physical-mechanical behavior of different raw materials used in production of ceramic tiles, allowing their analysis and processing in a simple, controlled and standard. Six unidentified raw materials donated by a ceramic coating industry from Cabo de Santo Agostinho were used. The samples were benefited and characterized per X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDX) and sedimentary particle size. After, raw materials were uniaxial pressing and subjected to controlled burning at 1000 ºC/ 1h with rate of 5ºC / min. Then, properties were evaluated per of linear shrinkage, water absorption, apparent porosity and flexural strength. The samples presented crystalline phases of kaolinite, quartz, mica and smectite, besides of alkaline oxides. The mechanical properties of samples showed the highest plasticity index (18%) and maximum strength went MP1 and MP6, 18% and 20.45 MPa, respectively. Thus, the raw materials presented physical properties for use in various applications in ceramic tile, such as ceramic.Item Resistência mecânica e térmica de compósitos reticulados de PVA/óxido de grafeno(2019-12-19) Silva, Felipe de Andrade Oliveira; Ghislandi, Marcos Gomes; http://lattes.cnpq.br/3409757365313853; http://lattes.cnpq.br/0379100954556428PVA composite films with citric acid and graphene oxide were synthesized via drop casting and crosslinked by heat treatment at 140° C for two hours. The influence of loads on mechanical, thermal and optical properties were characterized by tensile tests, thermogravimetry. and UV / VIS spectroscopy. The combined use of citric acid and graphene oxide proved to be very effective in promoting an increase in mechanical strength from 11.3 ± 1.4 MPa (pure PVA) to 37.1 ± 2.1 MPa (heat treated sample and 5% citric acid and 0.5% graphene oxide). However, there was a reduction in the maximum deformation from 333.0 ± 80.8% (pure PVA) to 84 ± 14%. The highest values obtained represent a 228% increase in mechanical strength and a 56% reduction in maximum deformation. The thermal stability of the films was analyzed by thermogravimetry; The addition of the fillers together with the heat treatment resulted in an increase in the degradation temperature from 269 ° C (pure PVA) to 325 ° C for the sample with 5% citric acid and 0.5 % graphene oxide. Optical properties were investigated by UV / VIS spectroscopy where yellowing due to heat treatment represented by a reduction in transmittance of 300-450 nm was observed. Keywords: Composites. Graphene. Cross-linkingItem Influência da corrente e taxa de alimentação na resistência à corrosão de revestimento à base da liga INCONEL 625 depositada por PTA-P(2019-12-10) Soares, Breno Luiz Santos; Santos, Aureliano Xavier dos; http://lattes.cnpq.br/0810494477757052Nowadays, the oil exploration process is still greatly affected by pipeline failures, which delay the production schedule, creates high maintenance costs, and creates risks to the environment and health. Thus, the search for less costly alternatives to minimize these impacts is constant, especially against failures due to corrosion. One of these is the use of materials that have high mechanical and anticorrosive properties in the form of coatings, which could be deposited by welding. The objective of this study was to evaluate the effects of the welding current and feed rate on the corrosion resistance of coatings based on the Inconel 625 alloy, deposited by PTAP process in API 5L X70 steel. The parameters were optimized using the factorial experimental design and the results analyzed by the Response Surface Methodology (RSM). Three deposits with ½ overlap were performed by PTA-P welding process, followed by an analysis of the dilution, iron content and corrosion resistance by electrochemical measurements. The coatings obtained with lower welding current and feed rate values showed better anti-corrosion properties.Item Síntese de nanomateriais de grafeno para utilização em nanocompósitos poliméricos(2019-07-11) Nogueira, Nathália Maria Barbosa; Ghislandi, Marcos Gomes; http://lattes.cnpq.br/3409757365313853; http://lattes.cnpq.br/3264027755950807Because of its unprecedented physical and chemical properties, graphene has attracted the attention of researchers searching to produce composite materials with unique properties. In this way, it has been studied the incorporation of graphene oxide loads into polymers and analyzed their influence on the mechanical, electrical and thermal behavior of the resulting composites. In this work, we present the preparation and the influence of the incorporation of graphene oxide (GO) on polyvinyl alcohol (PVOH). The mechanical reinforcement, by the incorporation of 0.5 wt%, 0.1 wt% and 1 wt% of graphene oxide into the polymer matrix, was estimated. The strategy involved the production of graphite oxide from graphite, using the modified Hummers method. The method was carried out by the addition of sulfuric acid (H2SO4), potassium permanganate (KMnO4) and hydrogen peroxide (H2O2), followed by the exfoliation of graphite oxide into sheets of graphene oxide by the use of ultrasound, and finally the preparation of the GO / PVOH nanocomposites by a simple solution mixing method. The synthesized materials were characterized by X-ray diffraction, Raman spectroscopy, and gravimetry. The analysis of the GO / PVOH films were carried out via tensile and UV-vis tests. Gravimetry showed that the solution of graphite oxide synthesized had a homogeneous concentration. X-ray diffraction (XRD) showed that the oxidative process of graphite precursor into graphite oxide was efficient. The stress-strain analysis confirmed the increase in mechanical strength of the polymeric film with the incorporation of graphene oxide load, while for the strain it was not possible to obtain conclusive data. The optical analysis showed a whitening of the film during the tensile test, indicating an alignment of the polymer chains and crystallization of the films. The UV-vis spectra showed that the pure PVOH film exhibited a high transparency, however, for the films with 0.1wt%, 0.5wt% and 1.0wt% GO this transparency decreased considerably.Item Influência da tensão, velocidade de alimentação e DBCP na resistência à corrosão de revestimentos à base da liga inconel 625 depositada por MIG(2019-07-09) Lima, Igor Jaloto de; Santos, Aureliano Xavier dos; http://lattes.cnpq.br/0810494477757052Annually, high investments are made in the maintenance of pipelines used in the oil industry around the globe. Thus, solutions are sought that combine low cost, reproducibility and properties that are consistent, mainly against corrosion. One of these is the use of materials that have high mechanical and anticorrosive properties in the form of coatings, which could be deposited by welding. The objective of this study was to evaluate the effects of different welding parameters on the corrosion resistance of coatings based on the Inconel 625 alloy, deposited by MIG process in API 5L X70 steel. The parameters were optimized using the factorial experimental design and the results analyzed by the Response Surface Methodology (RSM). Three deposits with ½ overlap were performed by MIG welding process, followed by a cross section cut in the samples for analysis of the dilution, iron content and corrosion resistance by linear potentiodynamic polarization (PPL) through corrosion potential (Ecorr), corrosion current (Icorr) and polarization resistance (Rp). The coatings obtained presented values of the dilution ranging from 5.8% to 15.01%. The coating that presented lower dilution value, also was the one with lower Icorr and Fe, besides higher Rp and Ecorr, thus, greater corrosion resistance.