Processo de ozonólise aplicado ao aproveitamento tecnológico de resísuos de coco verde

Abstract

The chemical analysis and structural analyzes of tropical biomass products has become a potential interest for the production of biofuels. Residues from coconut is promising because it doesn`t compete with the food industry and it can be transformed into a higher product added value due the lignocellulosic origin. Green coconuts had been separated between fiber and parenchyma following by anatomical characterization which it could better be understood and visualized the effect of pretreatment delignification; ozonolysis, with the chemical and compositional changes in the cell wall. To access the carbohydrates, lignin must be removed, thus it had been explored the changes induced by ozone under pH conditions; with addition of acetic acid and sodium hydroxide, and treatment time in milli-Q water. The ozonolysis was carried out at pH 3, 5 and 8 for 2; 4 and 6 hours at 25 ° C. Analyses were performed before and after the ozonolysis reaction to investigate the change of polysaccharides and lignin with the following techniques: SEM, Py-GC/MS, HPLC, FT-IR and TGA. With Scanning electron microscope and infrared spectroscopy, it was possible to observe the degradation of structural components of the fibers, in the form of "spring", from 4 hours of oxidation and changes in the intensities of the bands. According to the Py-GC/MS results, compounds resulting from lignin had been identified and stablished S/G ratio as 0,73. With a lignin Klason content of 26.28% from green coconut fiber and 25.45% from parenchyma. The best conditions of ozone treatment were determined to be the fiber with no addition of reagents for 4 hours under oxidation as determined by the increase of glucose content in the hydrolysate to 45.96 % after acid hydrolysis of ozone treated fibers.