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Calcination of Nickel Mud

References: 1. NASIRIAN, M. et al. 2017. Photocatalytic efficiency of Fe 2 O 3 /TiO 2 for degradation of typical dyes in textile industries: Effects of calcination temperature and UV-assisted thermal synthesis. Journal of Environmental Management [online]. Vol. 196 , pp. 487–498. [cit. 2017.03.27]. Available at: < http://www.sciencedirect.com/science/article/pii/S0301479717302451 >. 2. SOLDÁN, M. et al. 2013. Evaluation of the Structure of Industrial Wastes. Advanced Materials Research [online]. Vol. 664 , pp. 185–190. [cit. 2017

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Characterization of magnetic biochar amended with silicon dioxide prepared at high temperature calcination

1 Introduction Calcination process is considered to increase hardness of different composite materials and prevent their breakage [ 1 ]. Generally, high temperature selective environment-based calcination alters material textural and mineralogical characteristics, which for some composite materials improves surface properties and attracts their environmental applications [ 2 ]. However, Mahmood et al. [ 3 ] found reduction of pollutants removal in mixed oxides calcined at higher temperature. Numerous powdered materials have been utilized for toxic metals

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High Pressure Synthesis versus Calcination – Different Approaches to Crystallization of Zirconium Dioxide

.G. (1995). Characterization of zirconia-based catalysts prepared by precipitation, calcination and modified sol-gel methods, Ind. Eng. Chem. Res. 34, 78–82. DOI: 10.1021/ie00040a005. 23. Somiya, S. & Akiba, T. (1999). Hydrothermal zirconia powders: A bibliography, J. Eur. Ceram. Soc. 19, 81–87. DOI: 10.1016/S0955-2219(98)00110-1. 24. Amberg, M. & Gunter, J.R. (1996). Metastable cubic and tetragonal zirconium dioxide, prepared by thermal oxidation of the dichalcogenides, Solid State Ionics 84, 313–321. DOI: 10.1016/0167-2738(96)00020-3. 25. Kaddouri, A., Mazzocchia

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Production Method that Leads to TiO2 Nanofibrous Structure Usable in Food Packaging

References HE, F. – MA, F. – LI, J. – LI. T. – LI. G. 2014. Effect of calcination temperature on the structural properties and photocatalytic activities of solvothermal synthesized TiO 2 hollow nanoparticles. In Ceramics International, vol. 40, 2014, no. 5, pp. 6441–6446. ŠEVČÍK, L. – LEPŠÍK, P. – PETRŮ, M. – MAŠÍN, I. – MARTONKA, R. 2014. Modern method of construction design. In Book of Proceedings of 54 th International Conference of Machine Departments. Liberec : Technical University of Liberec, 2014. pp. 509–516. ISBN 978

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Effect of calcination temperature on the structural, optical and magnetic properties of pure and Fe-doped ZnO nanoparticles

-precipitation, hydrothermal reaction, and sol-gel synthesis. In the present work, we have synthesized ZnO nanoparticles using co-precipitation method. This is a simple and low cost method that gives good yield of the end product and takes less time to prepare the nanoparticles. In this research work we have studied the effect of calcination temperature on the structural and optical properties of ZnO nanoparticles. Further, we have also studied the effect of calcination temperature on the structural, optical and magnetic properties of Fe-doped ZnO nanoparticles. Organization of this

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FTIR study of hydrotalcite

Abstract

The aim of the research was the study of aluminium-magnesium hydrotalcite by FTIR analysis and detection of differences in structure due to calcination. Three types of samples were analysed. In the first two samples, cobalt was added into the structure and the third sample contained nickel and zinc. Hydrotalcite was prepared by one of the most common methods of hydrotalcite preparation, co-precipitation. After preparation, the samples were calcined at temperatures from 150 °C to 750 °C. Samples were compared in terms of calcination temperature; but in case of samples containing cobalt, two samples to each other. The most significant changes were noticed in the 500–700 cm−1 region, where a spinel structure was formed at higher calcination temperatures.

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Performance of dye-sensitized solar cell fabricated using titania nanoparticles calcined at different temperatures

Abstract

Synthesis of titania (TiO2) nanoparticles by sol-gel method and their calcination at different temperatures, viz 450 °C, 550 °C and 650 °C (defined as T450, T550 and T650) has been done. Structural analysis indicates that the T450 sample possesses anatase phase. The phase transformation to rutile starts occurring at T550, and, on increasing the calcination temperature, the crystallization and percentage of rutile phase increases. As the temperature increases from 450 to 650 °C, the crystallite size increases by about a factor of two from 11.5 to 20.2 nm. From SEM micrographs, T550 electrode has been found to have appropriate aggregation, which led to enhanced dye desorption, as compared to T450 and T650 based electrodes. TEM images of the synthesized nanoparticles reveal that the particle size increases from 7 to 28 nm on increasing the calcination temperature from 450 to 650 °C. From the photoluminescence and Fourier transform infrared studies, it has been concluded that the surface OH− groups are reduced on calcination, which affects the electron injection efficiency. The dye sensitized solar cell, fabricated using T550 sample, having a ratio of anatase/rutile 89:11, has been found to achieve the highest conversion efficiency.

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Synthesis of NiO nanoparticles by sol-gel technique

Abstract

NiO nanoparticles were fabricated by sol-gel route using ammonium hydroxide and nickel nitrate as precursors. The NiO nanoparticles were calcinated at 400 °C and 1000 °C. The nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), thermogravimetry analysis/differential thermal analysis (TGA/DTA). The structural properties were evaluated by X-ray diffraction (XRD). XRD confirmed the formation of well-crystallized and high purity NiO phase. The XRD showed that the peaks were sharpened and the crystallite size increased as the calcination temperature increased. The average crystallite size ranged from 12 nm to 20 nm, when calcined at temperatures 400 °C and 1000 °C, respectively. Fourier transform infrared spectroscopy (FT-IR) revealed the chemical composition and confirmed the formation of NiO nanoparticles. The nanoparticles showed paramagnetic behavior.

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Preparation and properties of calcium oxide from eggshells via calcination

Abstract

Duck eggs are one of the most versatile cooking ingredients in which residue eggshells are discarded. Raw duck eggshells were calcined at temperatures between 300 to 900 °C, for 1, 3, and 5 h. Both the raw and calcined duck eggshells were characterized by FTIR, STA, XRD, XRF, TEM, BET, a particle size analyzer, and an impedance analyzer. The proper calcination conditions are: 900 °C and 1 h, yielding calcium oxide with a purity of 99.06 % w/w. The calcium carbonate of the rhombohedral form (CaCO3) transforms completely into the calcium oxide or lime of the face centered cubic form (CaO) at 900 °C, as shown by XRD diffraction patterns. The transmission electron microscopy (TEM) images of the calcium oxide reveal a moderately good dispersion of nearly uniform particles. The calcium oxide has a white color, a spherical shape, high porosity, and narrow particles size distribution. The percentage of ceramic yield of the calcium oxide is 53.53, as measured by STA (TG-DTA-DTG). The calcium oxide has a N2 adsorption-desorption isotherm indicating the meso-porosity range. The dielectric constant and the electrical conductivity of the calcined calcium oxide are 35 and 1:0×10−6(Ω·m)−1, respectively, at the frequency of 500 Hz.

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The effect of calcination temperature on properties and activity of Cu/ZnO/Al2O3 catalysts

The effect of calcination temperature on properties and activity of Cu/ZnO/Al2O3 catalysts

The paper presents the results of the investigation on the influence of calcination temperature of Cu-Zn-Al catalyst precursor, on physicochemical properties and catalytic activity for water gas shift reaction. A model precursor of chemical composition corresponding with a typical commercial catalyst and prepared by coprecipitation method was studied. It has been shown that the temperature of calcination step determines the surface properties of the final catalyst, the active phase dispersion, and thus significantly affects the catalytic activity.

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