1. Physical and chemical properties of synthetic cryolite:

  

The product is a white crystalline powder or a sandy-size granularity, and a pinkish crystalline powder or a sandy-size granularity as well. Sp.gr.2.95—3.05g/cm3, melting point about 1025°C, specific heat 1.056j/g°C at 18—100°C. It's slightly soluble in water, but insoluble in anhydrous hydrogen fluoride. The content of its crystal water will be decreased while the increasing of the molecular ratio, therefore its loss on ignition will be also decreased while the increasing of the molecular ratio. After the paste of synthetic cryolite with different molecular ratio dehydrates, the loss on ignition at 800°C will appear 10.34%, 6.22% and 2.56% when the molecular ratio reaches 1.74, 2.14 and 2.63 reactively.

 

   
2. Applications: 
Metal surface treatment: As component in pickling pastes for stainless steel. 
Production of abrasives: As active filler in resinbonded adrasives for metal treatment. 
Production of enamel, glazing frits and glass: As abrasives, opacifying agent. 
Production of soildering agent: Component for fluxing agent. 
Production of welding agent: Component of weilding rod coatings and welding powders. 
Aluminum-metallurgy: As component of fluxing agents, protective and refining salts

 

3. Specification :

 

Ingredient	Super	First grade	Second grade
F%≥	53	53	53
Na% ≥	32	32	32
Al≥	13	13	13
H2O%≤	0.4	0.5	0.8
SiO2≤	0.25	0.36	0.4
Fe2O3%≤	0.05	0.08	0.10
SO4%≤	0.7	1.20	1.30
P2O5%≤	0.02	0.03	0.03
Ignite on 550oC≤	2.5	3.00	3.00
CaO%≤	0.10	0.15	0.20

 

 

4.Safety

Cryolite is poorly soluble in water which mitigates problems. Upon ingestion, however, the acids in the stomach increases this solubility. The LD50 = 200 mg/kg, comparable to that for soluble fluoride salts.