Title: Ferric Sulfate
CAS Registry Number: 10028-22-5
Additional Names: Ferric persulfate; ferric sesquisulfate; ferric tersulfate
Molecular Formula: Fe2O12S3
Molecular Weight: 399.88
Percent Composition: Fe 27.93%, O 48.01%, S 24.06%
Line Formula: Fe2(SO4)3
Literature References: Prepn: Gmelins, Iron (8th ed.) 59, part B, 439-462 (1932).
Properties: Grayish-white powder, or rhombic or rhombohedral crystals. Very hygroscopic. Commercial product usually contains about 20% water and is yellowish in color. d18 3.097. Slowly sol in water, rapidly sol in the presence of a trace of FeSO4; sparingly sol in alcohol; practically insol in acetone, ethyl acetate. Hydrolyzed slowly in aq soln. Keep well closed and protected from light.
Density: d18 3.097
CAUTION: Potential symptoms of overexposure are irritation of eyes, skin, mucous membranes; abdominal pain, diarrhea, vomiting; liver damage. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 174.
Use: In preparation of iron alums, other iron salts and pigments; as coagulant in water purification and sewage treatment; in etching aluminum; in pickling stainless steel and copper; as mordant in textile dyeing and calico printing; in soil conditioners; as polymerization catalyst.