The proposed project is of a developmental research type. The project proposes the optimization of silica synthesis from Philippine rice hullfor advanced ceramic applications. The optimization synthesis of silica from Philippine rice hull will be done by controlled-heat treatment, leaching, and simple acid precipitation method. The characteristics of the synthesized silica from the different treatments applied will be analyzed using TG-DTA, XRD, and XRF techniques for its thermal behaviour, structure, and composition respectively. The obtained silica from the optimum synthesis method will be utilized for ceramic porcelain body and glaze formulation to determine its potential as silica material for advanced ceramic applications.

Significance:

The significance of this proposed project includes mainly the conversion of agricultural waste rice hull (a by-product of milling rice grains) to worthy and value-adding products such as high purity silica. Silica is one of the major raw materials for ceramics especially in whiteware body and glaze formulations. The common source of silica for ceramic industries is sand or flint which is mined from a source (Ryan and Radford, 1987). The advantages of rice hull among other silica source are: its richness in silica; its abundance as waste due to limited use or low-value uses; amorphous or crystalline form of silica can be extracted; and is renewable.

With the huge amount of silica-rich rice hull in the Philippines including Ilocos Region, its utilization as silica source can circumvent the waste disposal problem and can be an alternative renewable source of this compound. With the possible uses and applications of silica from rice hull for ceramic industry, it is very important then to study its characteristics and synthesizing the desired silica form for optimum utilization. Furthermore, this proposed project may alleviate pollution problem, may reduce production cost of silica for possible various industrial applications (Kayal and Singh, 2010) as well as may increase income of farmers and rice growers; may contribute to the country's mandate on "The Ecological Solid Waste Management of 2000" which states that "research and development programs for improved solid waste management ..." (RA No. 9003); and may benefit the Ceramic Engineering students with regards to advanced ceramic technologies and applications for possible global recognition on research and development.

Methodology:

The experimental processes performed in this project study consist of four (4) major stages which are as follows:

Stage 1 - Characterization of rice hull and rice hull silica by TG-DTG technique

Stage 2 - Extraction of bulk silica by controlled heat treatment

Stage 3 - Synthesis of amorphous nanosilica via acid precipitation method

Stage 4 - Synthesis of crystalline silica from rice hull ash as a by-product of burning

Stage 5 - Characterization of the synthesized silica by XRD, XRF, and PSA techniques

Stage 6 - Utilization of the synthesized silica from rice hull for ceramic body and glaze formulation.

Plan of Work:

Phase 1: Gathering of rice hull materials and acquisition of supplies (Expected Output: Rice hull and rice hull ash samples)

Phase 2: Pre-treatment and initial characterization of rice hull (Expected Output: Thermal behaviour and chemical composition of the rice hull)

Phase 3: Silica synthesis via acid precipitation method and thermal treatment (Expected Output: Silica for characterization)

Phase 4: Characterizations of the synthesized silica (Expected Output: High purity amorphous nanosilica and crystalline silica from rice hull and optimum synthesis method is achieved)

Phase 5: Ceramic body and glaze formulation study (Expected Output: Ceramic body and glaze were produced utilizing synthesized silica from rice hull as filler)

Phase 6: Testing and Evaluation (Expected Output: The ceramic body formulated is of porcelain type and the glaze is transparent)

Phase 7: Manuscript writing (Expected Output: Technical report)