Characterization of Rice Husk and the Crystallization Process of Amorphous Silica from Rice Husk Ash

Published in: Engineering Innovations for Global Sustainability: Proceedings of the 14th Latin American and Caribbean Conference for Engineering and Technology
Date of Conference: July 20-22, 2016
Location of Conference: San Jose, Costa Rica
Authors: Ana Rivas
Grace Vera
Víctor Palacios
Andrés Rigail
Mauricio H. Cornejo Martínez
Refereed Paper: #93

Abstract:

Rice husk (RH) is a rich silica by-product of rice production with great potential for industrial applications. After combustion, a rice husk ash rich in silica is obtained, with some amount of other inorganic components constituted mainly of alkaline elements. The study was conducted to characterize both the rice husk and rice husk ash (RHA) in order to evaluate their constitution and the form in which mentioned impurities are present. The amorphous silica crystallized when heated under certain conditions. In this way, the examination of the crystallization process of rice husk ash with different impurity levels was also carried out by varying the temperature, time and heating conditions. The study reveals a preferential distribution of silica at the cell tip of the outer RH surface cells. The impurities form compounds with combinations of different elements such as Ca and Mg, P and K, and are mainly localized below the inner surface in the form of spherical and cuboidal shapes, as well as irregular morphologies.