Thermal decomposition of Nephelium lappaceum L. peel

Abstract

Influence of chemical pretreatment in thermal behavior of Nephelium lappaceum L. peels was studied through thermogravimetric analysis, SEM, X-ray diffraction, FTIR and EDXRF. Results of derivate thermogravimetry were deconvoluted with Fraser–Suzuki function, demonstrating that the distribution of pseudo-components is affected by chemical pretreatment, where sulfuric acid pretreated sample (Ras) has not indicated the cellulose pseudo-component peak and the phosphoric acid pretreated sample (Rap) also did not demonstrate the lignin peak, indicating itself to be an effective tool in the prediction of pseudo-components of lignocellulosic samples. This result corroborates with FTIR spectra and XRD. The sample Rna (sodium hydroxide treated) has indicated modifications in cellulose crystalline structure, conversion of cellulose I/II, revealed by XRD. An EDXRF analysis demonstrated that the chemical pretreatment also influenced the distribution of minerals, constituted essentially of Na, Mg, Fe, K, Al and Cl. This change is evidenced when carrying out statistical analysis of the samples, and principal component analysis applied in EDXRF data revealed statistical differences between samples, separating in distinct quadrants.