Pozzolanic characterization of Cuban bamboo leaf ash: Calcining temperature and kinetic parameters

Abstract

The paper presents a study of the pozzolanic activity of Cuban bamboo leaf ash. To evaluate the pozzolanic activity a conductometric method was used, which is based on the measurement of variation in electrical conductivity of a bamboo leaf ash (BLAsh)/lime solution with reaction time. Later, the kinetic parameters (in particular, the reaction rate constant and free energy of activation) are quantified by applying a kinetic-diffusive model. The pozzolanic activity is quantitatively evaluated according to the values obtained of the kinetic parameters. Other experimental techniques, such as X-ray diffraction and scanning electron microscopy, which complement the results coming from the conductometric method, were applied. Also, the paper reports on the influence of calcining temperature (500, 600 and 700 C) on the pozzolanic activation of the bamboo leaves. The results show good pozzolanic properties of bamboo leaf ashes for temperatures between 500 and 700 C, and only a little difference on the activation of bamboo leaf ash as a function of the calcining temperature applied. The BLAsh calcined at 500 C showed the highest pozzolanic activity.