Physicochemical Characteristics of Mauritia arabica Shell with High Temperature Calcination

Abstract

Mauritia arabica shell (MAS), is widely applied as a Chinese tradition medicine after thermal decomposition. However, it is still uncertain how the thermal decomposition process affects the physicochemical properties of MAS. Moreover, the influences of these properties on the bioavailability have not been well understood. In this investigation, a temperature-programmed pyrolysis process is applied to calcine MAS to achieve the desired MAS with different physicochemical properties. The results showed that a weight loss of 43.27% - 44.73% was detected after MAS was calcined at 900°C, which was mainly attributed to the decomposition of protein, the phase transition of calcium carbonate from aragonite to calcite, and the decomposition of calcium carbonate. The activation energy in the heating duration was calculated by applying the Kissinger-Akahira-Sunose model (KAS), which was 58.13 kJ/mol for crystalline transformation and 181.27 kJ/mol for decomposition. Besides,according to the analyses from Fourier transform infrared (FTIR) and X-ray powder diffraction (XRD) tests, the crystalline of calcium carbonate in MAS was aragonite. These results provide beneficial temperature parameters for the pretreatments of MAS for pharmaceutical usages.