Showing posts with label Hard Chrom Plating. Show all posts
Showing posts with label Hard Chrom Plating. Show all posts

Saturday, March 28, 2009

Chromic Acid

Chromic Acid (Chromium Trioxide)
CAS : 7738-94-5. CrO3
The true chromic acid name for H2CrO4, Chromium Trioxide in solution.
Properties : Dark puplish or red crystal flake. Soluble in water, alcohol, and mineral acid. Deliquescent.
Density : 1.67 - 2.82.
Melting point : 196 C.


Derivation :
- Added Sulfuric acid to a solution of Sodium dichromate and the the product is crystallized out.
- Chromite is fused with soda ash and limestone and then treated with sulfuric acid.
Grade : Technical, CP.
Hazard : Powerful oxidizing agent, may explode on contact with reducing agents, may ignite on contact with organic material. A poison. Corrosive to skin. TLV : 0.05 mg/m3 of air. A human carcinogen.
Use : Chromium Plating intermediate, medicine (caustic), process engraving, anodizing, ceramic glazes, colored glass, inks, Tanning, paints, textile mordant, etchant for plastics.

Function in Chrom Plating : Hexavalent Chromium base in Decorative Chrom Plating and Hard Chrom Plating.