Aluminum Chloride
AlCl3·6H2O
241.43
241.43Aluminum chloride, hexahydrate.
Aluminum chloride hexahydrate
[7784-13-6].Anhydrous 133.34
[7446-70-0].» Aluminum Chloride contains not less than 95.0 percent and not more than 102.0 percent of AlCl3, calculated on the anhydrous basis.
Packaging and storage—
Preserve in tight containers.
Water, Method I 
921
:
between 42.0% and 48.0%.
921:
between 42.0% and 48.0%.
Sulfate—
The addition of 0.2 mL of barium chloride TS to 10 mL of a solution (1 in 100) produces no turbidity within 1 minute.
Limit of alkalies and alkaline earths—
To a boiling solution of 1.0 g in 150 mL of water add a few drops of methyl red TS, then add 6 N ammonium hydroxide until the color of the solution just changes to a distinct yellow. Add hot water to restore the volume to 150 mL, and filter while hot. Evaporate 75 mL of the filtrate to dryness, and ignite to constant weight: the weight of the residue does not exceed 2.5 mg (0.5%).
Heavy metals, Method I 231—
Dissolve 1 g in 1 mL of 1 N acetic acid and sufficient water to make 25 mL: the limit is 0.002%.
231—
Dissolve 1 g in 1 mL of 1 N acetic acid and sufficient water to make 25 mL: the limit is 0.002%.
Iron 241—
Dissolve 1.0 g in 45 mL of water, and add 2 mL of hydrochloric acid: the limit is 0.001%.
241—
Dissolve 1.0 g in 45 mL of water, and add 2 mL of hydrochloric acid: the limit is 0.001%.
Assay—
Procedure—
Transfer to a 250-mL volumetric flask about 5 g of Aluminum Chloride, accurately weighed, dissolve in and dilute with water to volume, and mix. Transfer 10.0 mL of the solution to a 250-mL beaker, and add, in the order named and with continuous stirring, 25.0 mL of Edetate disodium titrant, and 20 mL of acetic acid-ammonium acetate buffer TS, and boil gently for 5 minutes. Cool, and add 50 mL of alcohol and 2 mL of dithizone TS. Titrate with 0.05 M zinc sulfate VS to a bright rose-pink color. Perform a blank determination, substituting 10 mL of water for the assay preparation, and make any necessary correction. Each mL of 0.05 M Edetate disodium titrant is equivalent to 6.667 mg of AlCl3.
Auxiliary Information—
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| Topic/Question | Contact | Expert Committee |
| Monograph | Feiwen Mao, M.S.
Scientist 1-301-816-8320 |
(MDOOD05) Monograph Development-Ophthalmics Oncologics and Dermatologicals |
USP32–NF27 Page 1478