Zirconia (ZrO2) nanoparticles with nonstabilized monoclinic and sodium‐stabilized cubic phase were produced from zircon sand using the ball mill‐aided precipitation route. Characterization and a comprehensive study of nanocrystalline ZrO2 particles were expressed by X‐ray diffraction, particle size distribution (PSD), Fourier transform infrared spectroscopy, thermal analysis, Brunauer–Emmett–Teller surface area and pore size analysis, X‐ray fluorescence spectrometry, scanning electron microscopy, and transmission electron microscopy. In this article, the influence of the processing parameters on the crystalline phase, particle size, PSD, aggregation, and morphology are reported. The experimental results prove that the precipitation leads to aggregated particles, which are disaggregated by the ball‐milling process. The ball‐milling process strongly influences the formation of uniform‐sized spherical particles with a high surface area. Fully crystalline monoclinic ZrO2 nanoparticles with an average particle size of 64 nm (d50) and the specific surface area of 126 m2/g were obtained. In addition, the sodium‐stabilized cubic ZrO2 nanoparticles with an average particle size of 39 nm (d50) and the specific surface area of 227 m2/g were obtained with the help of the ball‐milling process. In the present process, a simple reaction scheme is developed for the large‐scale production of stabilized and nonstabilized ZrO2 nanoparticles using inexpensive precursor obtained from zircon sand.

Nanosized TiO2 was obtained using a simple chemical route from natural ilmenite available in Tamilnadu, India. The nano‐TiO2 particles obtained were comprehensively characterized by X‐ray diffraction, FTIR, BET surface area, particles size, and transmission electron microscopic analysis. The results observed reveal that the nano‐TiO2 show a rutile crystal structure with an average particle size of 50 nm and a specific surface area of 112.64 m2/g with spherical morphology. Different proportions of nanotitania were added in silica brick composition to determine out the amount of tridymite phase transformation. It was observed that the addition of 0.5 wt% nano‐TiO2 leads to highest amount of tridymite phase formation. The effect of incorporation of nano‐TiO2 in silica refractory was explored in terms of refractory properties such as bulk density, apparent porosity, cold crushing strength, refractoriness under load, creep in compression, and reversible thermal expansion.

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The nano alumina have been synthesised employing a novel eco-friendly route from natural bauxite ore. The synthesis of alumina powder from natural bauxite is of great interest owing to the fact that it enables mass production without the use of expensive chemical resources and processing techniques. Employing the Bayer process, synthesis of nano alumina has been made from natural bauxite followed by sol-gel route. The ultra fine alumina powder with high surface area is obtained through the digestion of gel followed by sintering. The size of the particle and its morphology was controlled by calcination temperature and processing time. The crystallite size of the nano alumina powder has been measured using XRD pattern and the FTIR spectrum of nano powder after calcination at different temperatures (873 K and 1273 K) were measured. The results from the energy dispersive X-ray analysis (EDAX) and morphological studies reveal interesting informations. The observed results indicate that one can control the particle size by controlling the aging and calcination temperature. The obtained results indicate that the above process technique is an unique method for the preparation of nano alumina (Al2O3) from natural source such as bauxite.