SUBSTITUTION OF RICE HUSK ASH FOR QUARTZ IN CERAMIC WALL TILES FORMULATION

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Author

Presented To

Department of Medicine

ABSTRACT
The processing of rice has been cited as a source of waste that contaminates and pollutes the environment. Waste addition into production cycles represents an alternative form of restoration, which is interesting from both environmental and economic standpoints. Technological development trends towards utilization of waste as a means of cost reduction in industrial processing has attracted the use of rice husk ash (RHA) as a value added material. Rice husk which is an agricultural waste was investigated for its SiO2 content and was utilized as a replacement for quartz for the formulation of wall tile bodies. In this study, the development of ceramic wall tile formulations containing silica from rice husk ash as a replacement for quartz was investigated. Six formulations using the raw materials, kaolin, ball clay, whiting, and quartz/rice husk ash were selected and used in the mixture design. The elemental analysis of the RHA generated from the open air burning of rice husk and the other materials used for the study was carried out using X-ray Fluorescence Spectrophotometer (XRF) and the result indicated that the RHA had a high concentration of SiO2 (82.1%) with a very low impurity content. A process was developed to utilize the RHA in ceramic wall tile formulation. The experimental samples were fired in an electric kiln at the sintering temperature ranges of 1100oC, 1140oC and 1160oC and characterized. The drying and firing shrinkage values were measured according to ASTM C 326 – 82, water absorption, apparent porosity and apparent specific gravity were determined by ASTM C 373 – 88 and flexural strength was determined by ASTM C 648. The morphological characterization of the formulations was performed by scanning electron microscopy (SEM) on fracture surfaces of the samples. At the optimum temperature of 1160oC shows the typical sequence of enhanced densification. The sintering temperature of 1160oC was found suitable for the wall tile formulations containing RHA.