Preparation of Mullite Nanocomposites Powders by the Hydrothermal Crystallization Method from Coal Gangue
| Periodical | Key Engineering Materials (Volumes 512 - 515) |
|---|---|
| Main Theme | High-Performance Ceramics VII |
| Edited by | Wei Pan and Jianghong Gong |
| Pages | 49-53 |
| DOI | 10.4028/www.scientific.net/KEM.512-515.49 |
| Citation | Ling Xin Tong et al., 2012, Key Engineering Materials, 512-515, 49 |
| Online since | June, 2012 |
| Authors | Ling Xin Tong, Jin Hong Li, Fang Liu |
| Keywords | Coal Gangue, Hydrothermal Crystallization, Mullite Nanocomposite |
| Price | US$ 28,- |
Mullite nanocomposites powders have been successfully synthesized from pretreated coal gangue via hydrothermal crystallization process. The mullite nanocomposites powders are investigated and charactered by laser particle size analysis, X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM) analysis, selected area electron diffraction (SAED) analysis and energy-dispersive X-ray (EDX) analysis. Moreover, the reaction mechanism of this process is speculated according to MAS-NMR results. It is indicated that mullite nanocomposites powders can be prepared at 80-90 ◦C for 3 h with NaOH concentration of 2-4 mol/L and L/S ratio (liquid/solid ratio in mass) of 10 mL/g by using calcined coal gangue as precursor. The agglomerate powder size of D50 is about 3.83-4.71 mm. Furthermore, some imperfective puncheon-shaped crystals exist among a large number of whole puncheon-shaped crystals which are about 30-70 nm in length and about 10-20 nm in diameter. MAS-NMR analysis indicates that the nano-size mullite grow around the central atom-Al, Si of [AlSi]O4 tetrahedral and the growth unit Al[OH]4- exist in this process definitely.
