Cenosphere sometimes called microsphere, is a light weight, inert, hollow sphere made largely of silica and alumina and filled with air or inert gas, typically produced as a byproduct of coal combustion at thermal power plants. The color varies from gray to almost white and their density is about 0.6–0.9 g/cm³, all these property give it a widely application for insulation, refractory, oil drilling, coating, construction use.
Chemical Composition:
| Element | Content(%) |
| SiO2 | 50-55 |
| Al2O3 | 28-33 |
| MgO | 0.8-1.2 |
| CaO | 0.2-0.4 |
Physical Property:
| Item | Result |
| Color | Grey or light grey |
| Melting point | 1400℃ |
| Floating rate | 90 min |
| Moisture | 0.5% max |
| PH | 6 |
Specification: 20mesh, 30mesh, 40mesh, 60mesh, 100mesh.