Production of silica-based ceramics sintered under nitrogen atmosphere from rice husk and sugarcane bagasse ash

Abstract

Nitride silica-based ceramics were prepared by sintering under nitrogen atmosphere using rice husk ash and bagasse ash as raw materials. X-ray Fluorescence Spectrometry (XRF) and X-ray Diffractometor (XRD) studies revealed that the main phase of rice husk ash (after calcined at 600°C for 6 h.) was amorphous silica, whereas the sugarcane bagasse ash contained quartz and CaCO3. Thus, both ashes would be a good source for silica. Two batches of the 100 wt% rice husk ash (RHA100) and the mixture of 50 wt% rice husk ash and 50 wt% bagasse ash (RHA50BA50) were wet milled using planetary ball milling machine, and were then dried at 90°C. The powders were uniaxially pressed at the pressure of 150 MPa. The disk shape samples were sintered at 1300-1500°C in the nitrogen atmosphere with gas flow rate of 600 ml/min. The physical and mechanical properties of the sintered disk shape samples were determined. The phase structure and microstructure of the samples were investigated using XRD and SEM techniques, respectively. The main phases obtained after sintering were cristobalite, tridymite, α and β-silicon nitride and SiC. The RHA50BA50 sample sintered at 1450°C showed the optimum properties with low firing shrinkage, low water absorption and high strength.

Structure and Properties of Silver-Silica Composite Prepared From Rice Husk Silica and Silver Nitrate

“…In addition, the obtained rice husk silica is also known to have an amorphous phase [20][21] and has almost the same ortho silicate structure [22], which is found in transition metal alkoxides and silicon alkoxides, such as tetra ethyl ortho silicates (TEOS) and tetra methyl ortho silicates (TMOS), so that the silica from rice husks has the potential to be used as a substitute for TEOS and TMOS. Based on the physical properties of the silica, such as the large surface area, good heat resistance, high mechanical strength, and inertness, it is shown that the silica can be used as a catalyst [23][24], adsorbent [25], filler [26][27], silica gel [28][29], and composite [30][31].…”

Reduction of Methylene Blue Using Silica Nanoparticles Obtained from Waste ZrC

“…[14][15][16][17][18][19] In recent years, rice husk and wheat husk as silica precursors with high silica content and cheap raw material costs (agricultural wastes) have been employed to manufacture SiO 2 . [1,3,20,21] Also, the silica prepared for use in the aforementioned applications must be of high purity. As a result, many methods for removing silica impurities have been reported.…”

“…Furthermore, because silica nanoparticles (SiO 2 NPs) are widely used in a variety of applications such as textiles, food rheology modifiers, adsorbents, pharmaceuticals, and the chemical industry, the development of nano‐silica fabrication methods is essential [14–19] . In recent years, rice husk and wheat husk as silica precursors with high silica content and cheap raw material costs (agricultural wastes) have been employed to manufacture SiO 2 [1,3,20,21] . Also, the silica prepared for use in the aforementioned applications must be of high purity.…”