The non-isothermal combustion process of hydrogen peroxide treated animal bones. Kinetic analysis

Abstract

The non-isothermal combustion process of hydrogen peroxide (H(2)O(2)) treated animal bones was investigated by TG-DTA techniques. The kinetic triplet for the investigated combustion process was established, using different calculation methods. The investigated process occurs through three reaction stages. It was established that the first stage can be described by the reaction model, which contains two competing reactions with different values of the apparent activation energy, whereas the second reaction stage can be described by the third order reaction model, f(alpha)=(1 - alpha)(3). The hydrogen peroxide treatment reduced the kinetic complexity of organic phase degradation, compared to the same process in untreated bones. From interpretation of TG-DTA results, the third reaction stage can be attributed to the combustion of organic components, which arises from degradation of residual organic material. The appearance of the compensation effect for the investigated process, clearly shows the existence of three characteristic branches attributed to the different reaction stages. It was concluded that the degradation and combustion processes do not happen as a single thermal transformation. (C) 2011 Elsevier B.V. All rights reserved.