EXTRATO DE HIBISCO-COLIBRI COMO INIBIDOR VERDE DE CORROSÃO DO AÇO-CARBONO EM ÁCIDO SULFÚRICO

• Autor(a) principal: Valbon,Arthur
• Data de Publicação: 2019
• Outros Autores: Ribeiro,Bruno F., Soares,Maria Augusta F., Oliveira,Márcia C. C. de, Neves,Marcelo A., Echevarria,Aurea
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Química Nova (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422019004700797
• topic: Malvaviscus arboreus; corrosion inhibitor; ecofriendly inhibitor

For this work, a hydroalcoholic extract was prepared from the aerial parts of the Malvaviscus arboreus (Malvaceae) species, popularly known as hibisco-colibri in Brazil; and then, investigated by infrared and NMR spectroscopy. A class of special metabolites containing a porphyrin skeleton and pyrrole units was determined by typical absorption spectra, mainly 1H and 13C NMR, thus indicating the capability of showing anti-corrosion effect. Therefore, the M. arboreus extract was examined as a corrosion inhibitor for AISI 1020 carbon steel in H2SO4 1 mol L-1, using a mass loss (gravimetric) technique. Results showed good corrosion inhibition efficiency, at both time and temperature variation. The maximum efficiency observed at 500 ppm was 97.5%, at 3 h, 24 h and 48 h. The surface morphology was analyzed by scanning electron microscopy (SEM), through which a higher homogeneity was observed in the presence of the M. arboreus extract. The hydroalcoholic extract of hibisco-colibri can be considered an efficient green agent for preventing corrosion.