Valorization of Rice Husk Ash as Secondary Raw Material in the Ceramic Industry

摘要

In this work the screening results of the scientific activity conducted on the possibility to use rice husk ash as silica precursor in ceramic materials, such as ceramic pigments and brick, were reported. The selected pigment, the yellow (Zr,Pr)SiO_4 was synthesized by solid state reactions and the colour developed in a suitable ceramic glaze was investigated in comparison with the colour developed by the pigments prepared from pure SiO_2. Besides, laboratory bricks were obtained by extrusion, adding rice husk ash (5-20 wt%) to clayed materials, and characterized following the technical rules after drying and firing.