Abstract

In this research work a synthetic review of the quantitative characterization of various materials (sugar cane waste ashes, bamboo leaf ash, calcined paper sludge, loessic soils, zeolite, fly ash and silica fume) based on the computing of the kinetic parameters of the pozzolanic reaction in pozzolan/calcium hydroxide(CH) systems is offered. The paper presents of more relevant results in the quantitative characterization (computing of the kinetic parameters) of the pozzolanic reaction of different materials originated from agriculture, mining or industry activities carried out by the authors.Two pozzolanic activity tests (conductometric method and accelerated chemical method) are employed. A kinetic-diffusive model (published by the authors in previous works) is used to describe the pozzolanic reaction. The kinetic parameters that characterize the process (in particular, the reaction rate constant and free energy of activation) are determined with relative accuracy in the fitting process of the model. The pozzolanic activity is quantitatively evaluated according to the results obtained for the kinetic parameters. This allows the comparison in a direct way of the pozzolanic reactivity of the materials, which is very useful for the employment of these materials for envisaged applications. The values of the reaction rate constant jointly with the free energy of activation give a precise index of the reactivity or pozzolanic activity of the materials. Complementary experimental techniques, such as X-ray diffraction (XRD) and scanning electron microscope (SEM), were also employed, but not shown in the paper for space reason since that would necessitate a much larger paper.

Keywords: Quantitative characterization; Pozzolanic activity; Kinetic parameters; Kinetic-diffusive model

Abbreviations: SCBA: Sugar Cane Bagasse Ash; SCSA: Sugar Cane Straw Ash; BLA: Bamboo Leaf Ash; CPS: Calcined Paper Sludge; LS:Loessic Soils;FA: Fly Ash; SF: Silica Fume