Refractory Materials are usually non-metallic materials having those chemical and physical properties that make them applicable for structures, or as components of systems, that are exposed to environments above 1,000 °F (811 K; 538 °C)。

Sodium sulfate

Specs.:
Item | Super-fine | Standard |
Na2SO4 % min | 99 | 99 |
Non-soluble in water% max | 0.1 | 0.1 |
CaSO4 %max | 0.1 | |
NaC1 % max | 0.003 | 0.002 |
MgSO4 % max | 0.5 | |
Moisture % max | 0.1 | |
PH | 6-8 | 6-8 |
Size:1-60mesh | 90 |