APRESENTAÇÃO - História Antiga: Diferentes Perspectivas

AUTOR(ES)

Faversani, Fábio; Santos, Dominique Vieira Coelho dos; Rosillo-López, Cristina

FONTE

Rev. Bras. Hist.

DATA DE PUBLICAÇÃO

2020-08

RESUMO

Biodiesel is a suitable alternative to replace the petro-diesel. The biodiesel is formed by unsaturated esters easily degraded by interferences of oxygen, temperature, contact with metals or contaminants. The aim of this research was to investigate the biodiesel degradation process via 1H nuclear magnetic resonance (NMR) spectroscopy, observing the olefinic, bis-allylic and allylic protons signals of the chemical bonds, and by the induction period of the Rancimat. Biodiesel samples with metallic ions (Fe and Cu) and with rosemary natural extract were analyzed. The metal compounds showed a catalytic effect in the samples and the rosemary natural extract showed to be efficient by retarding the degradation process. The extract was ineffective in the presence of iron. Through the 1H NMR spectra was possible to observe changes in the signal intensities of the olefinic, bis-allylic and allylic protons as well as the formation of oxidation products in the biodiesel in the degradation process.

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