Preparation of forsterite refractory using highly abundant amorphous rice husk silica for thermal insulation

Abstract

The aim of the study was to investigate the effect of amorphous silica on the phase formation and study the physical characteristics of forsterite refractory prepared from quartz and MgO powder. Various samples were subjected to sintering temperature around 1100 • C and development of forsterite phase was characterized using Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The result indicate that the addition of rice husk ash (RHA) significantly affect the formation of forsterite phase. As the amount of RHA increased, it led to a better reaction between amorphous silica and periclase, later that will transform into forsterite phase at a temperature around 1100 • C. Formation of forsterite resulted in decrease of density, porosity, and thermal conductivity, while the opposite was observed for Cold Crushing Strength. Formation of forsterite phase was identified by XRD analysis of the sample. Based on the characteristics, the samples were considered as an insulator and of the potential use as refractory devices.

Bituminous Composite Comprising Amorphous Silica From Rice Husks

“…Rice husks were used to extract and obtain the silica by following the literature in previous studies [15]. The sol obtained is dripping with a 5 % HCl solution until the sol turns completely into a gel.…”

“…Based on several studies, the potential of rice husks was investigated in recognition of its high purity and reactive silica [1][2], and the solubility of the silica in an alkaline solution, thus enabling the production of rice husk silica in the form of sols. In addition, rice husk silica is known as a porous and high-grade amorphous material [3][4][5][6][7], which has the potential to become a suitable raw material for the production of various silica-based materials, such as the production of a nano-silica [1,[8][9], zeolite [10][11][12], mullite [13][14], forsterite [15][16], nepheline [17] and cordierite [18].…”

Effects of rice husk ash and wollastonite incorporation on the physical and thermal properties of refractory ceramic composites

“…This occurs because in this situation, where there is an excess of silica in relation to the stoichiometric proportion of the mullite, a part of the silica reacts with the alumina initiating the phase nucleation while another part becomes cristobalite and enters the existing pores decreasing the porosity of the material and the remainder remains in the form of quartz. However, when there is an excess of alumina a smaller amount of liquid phase is formed and consequently there is no excess of silica in the form of cristobalite to fill the material pores, therefore a greater porosity occurs [20,21,22]. For samples AS10W5, AS10W10 and AS10W20 the increasing in porosity compared to formulation A is associated with two factors.…”

“…As the temperature increases, the liquid is gradually enriched in aluminum ions until it reaches the stoichiometry of the mullite phase [19]. For this reason, some authors [20,21,22] that used clays that already had a higher silica/alumina ratio, report a reduction in porosity of the material after the introduction of another silica source. This occurs because in this situation, where there is an excess of silica in relation to the stoichiometric proportion of the mullite, a part of the silica reacts with the alumina initiating the phase nucleation while another part becomes cristobalite and enters the existing pores decreasing the porosity of the material and the remainder remains in the form of quartz.…”

Characteristic of Silica Level (SiO3) Resulted from the Extraction of Rice Husk Ash with KOH Solvent towards the Amount of Heating Time

“…When silica gel is used for coating materials like already performed using a fan, the materials will eventually have a high flash point [10,11], thus by adding silica gel on certain material can increase the material property. By using the extraction method, silica can be produced by rice husk ash [12]. In the study of Ya-Yu Hsieh [13], the rice husk ash can produce Si, Cl, Na and K elements, where the elements resulting from extraction can be utilized as needed.…”