Kinetic mechanism of magnesium production by silicothermic reduction of CaO·MgO in vacuum
| Autor: | Jianxun Song, Shao-long Li, Ji-lin He, Geng-peng Mai, Yu-si Che, Jian-hong Yi |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Thermogravimetric analysis Materials science Magnesium Metals and Alloys Analytical chemistry Pellets chemistry.chemical_element 02 engineering and technology Activation energy 021001 nanoscience & nanotechnology Geotechnical Engineering and Engineering Geology Condensed Matter Physics Kinetic energy 01 natural sciences Chemical reaction law.invention Ferrosilicon chemistry law 0103 physical sciences Materials Chemistry Calcination 0210 nano-technology |
| Zdroj: | Transactions of Nonferrous Metals Society of China. 30:2812-2822 |
| ISSN: | 1003-6326 |
| DOI: | 10.1016/s1003-6326(20)65423-1 |
| Popis: | The investigation of silicothermic reduction of CaO·MgO was carried out using a self-developed thermogravimetric analysis (TGA) instrument under vacuum and high temperature conditions. The TG data of pellets prepared with calcined dolomite, ferrosilicon and fluorite were determined at the heating rates of 1.5, 2.0, 2.5 and 3.0 °C/min in 5 Pa vacuum at 300–1400 °C, respectively. Model-free analysis and model-based analysis were applied for simulating the kinetic mechanism. By analyzing the characteristics of the initial and final reaction temperatures of TG curve, ratio of half-width of derivative TG curve and kinetic parameters, a conclusion was made that the most probable mechanism function is the first order formal chemical reaction with activation energy of 233.42 kJ/mol and pre-exponential factor of 5.14×1010 s−1. This study provides the basic data of dynamics of silicothermic magnesium production under vacuum conditions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect