CORROSÃO E BIOCORROSÃO EM BIODIESEL E DIESEL S10 DO COBRE ELETRODEPOSITADO SOBRE AÇO CARBONO

• Autor(a) principal: Johann, Julian
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações do UNICENTRO
• Texto Completo: http://tede.unicentro.br:8080/jspui/handle/jspui/1075
• topic: biocombustível; ensaios eletroquímicos; aço carbono SAE 1045; biofuel; electrochemical tests; carbon steel SAE 1045; CIENCIAS EXATAS E DA TERRA::QUIMICA; ENGENHARIAS; CIENCIAS BIOLOGICAS; CIENCIAS SOCIAIS APLICADAS::ADMINISTRACAO

Among the metal most used in industry and the automotive industry is the carbon steel, and sometimes with a coating of other metals or materials. Also they employ zinc alloys with iron, nickel or aluminum, and aluminum, metallic copper and tin. Similarly stainless steel and galvanized carbon steel has been widely used because they have a good value for money. However, it is known that metallic materials suffer corrosive processes, which are characterized by the degradation of a function of the metal through its reaction with other metals and it is in contact. When the metal part is damaged, it must be replaced, resulting in high maintenance cost of the equipment where you are. In addition to the costs for replacement of corroded parts, there are the indirect losses to loss of product, process efficiency loss and contamination by corrosion products. more paying attention to this process when it occurs in the middle of fuels, it is noted that the determination of corrosion is possible by means of electrochemical techniques, however, such as fuels having low conductivity, this measurement becomes difficult. There are also standards like ABNT 14359 and standards such as ASTM D130 establishing methods for determining the corrosion of fuel, however, corrosion is assessed qualitatively by visual comparison with standards, which can lead to results of uncertainty. In this context, the indirect determination of corrosion in fuel is an alternative, since it is based on the fuel and subsequent immersion metal immersion in a strong electrolyte, enabling the quantification of corrosion occurring by electrochemical data. In this study, we applied an indirect method for determination of corrosion and metal substrates biocorrosion carbon steel, copper and carbon steel coated with copper. Initially, the metal substrates were immersed in B100 biodiesel or diesel S10 and thereafter in a NaCl solution 0.5 mol l-¹ for potential open circuit measurements, electrochemical impedance spectroscopy and anodic potentiodynamic polarization measurements. Also vi employed the weight loss methods, evaluating the corrosion rate by varying the mass of the sample, and scanning electron microscopy (SEM) which consists of a morphological analysis of the sample to the evaluation of corrosive processes occurring in it. The methodology is showed as an efficient alternative and easily performed to evaluate the corrosion of metal samples. The open circuit potential measurements (PCA) showed that the copper coating changed the base metal PCA when immersed in biodiesel by shifting it to more negative values, indicating less resistance to corrosion. The samples immersed in diesel fuel showed higher impedance values, suggesting that biodiesel is more corrosive. Higher current densities were measured in the polarization of the samples coated with copper, indicating a lower corrosion resistance. In microbiological corrosion tests the highest impedance values were obtained for the sample that had the copper coating, demonstrating that this condition has lower corrosion resistance.