FCCV标准-Sodium Diacetate乙酸钠.pdf

Monographs/ Sodium Diacetate/411
TESTS
Lead Not more than 2 mg/kg.
Water Between 8.5% and 10.0%.
Assay Transfer about 350 mg of sample, accurately
weighed, into a 250-mL beaker. Add 100 mL of glacial acetic
acid, stir until completely dissolved, and titrate with 0.1 N TESTS
perchloric acid, using crystal violet TS as the indicator.
Assay Transfer about 500 mg of sample, accurately
Caution: Handle perchloric acid in an appropriate
weighed, into a 125-mL Erlenmeyer flask, dissolve it in 25
fume hood.
mL of glacial acetic acid containing drop of a 1: 100 p-
Each milliliter of 0.1 N perchloric acid is equivalent to 8.602 naphtholbenzene:glacial acetic acid solution that has been
mg of C6H5Na3O7
previously neutralized to a blue color, and titrate with.I N
perchloric acid to the original blue color. Each milliliter of
Alkalinity A solution of 1 of sample in 20 mL of water 0.1 N perchloric acid is equivalent to 19.01 mg of CgH-NaO4
is alkaline to litmus paper. Add 0.2 mL of 0. N sulfuric acid.
No pink color appears when 1 drop of phenolphthalein TS is Caution: Handle perchloric acid in an appropriate
added.
fume hood.
Lead Determine as directed in the Flame Alomic Absorption Lead Determine as directed in the Flame Atomic Absorption
Spectrophotometric Method under Lead Limit Test, Appendix Spectrophotometric Method under Lead Limit Test, Appendix
IlIB, using a 5-g sample.
IIIB, using
a 10-g sample.
Water Determine as directed under Water Determination, Water Determine as directed under Water Determination,
Appendix IIB.
Appendix IIB
Packaging and Storage Store in tight containers
Packaging and Storage Store in well-closed containers.
Sodium Dehydroacetate
Sodium Diacetate
Sodium 3-(1-Hydroxyethylidene)-6-methyl-1, 2-pyran-
Sodium Hydrogen Diacetate
2,4()-dione
H3C0O
H 3COONa3 CH3COOH-xH2O
C-CH H20
C4H7Na04xH2O
Formula wt, anhydrous 142.09
ONa
INS:262
CAS:126-96-51
C H,
Formula wt 208.15
DESCRIPTION
INS:266
cAS:[4418-26-2]
Sodium Diacetate occurs as a white, hygroscopic, crystalline
solid. It is a molecular compound of sodium acetate and acetic
DESCRIPTION
acid. One gram is soluble in about 1 mL of water. The pH
of a 1: 10 aqueous solution is between 4.5 and 5.0.
Sodium Dehydroacetate occurs as a white or nearly white
powder. One gram dissolves in about 3 mL of water, in 2 Function Sequestrant; preservative; antimicrobial agent;
mL of propylene glycol, and in 7 mL of glycerin.
mold inhibitor.
Function Preservative.
REQUIREMENTS
Identification A 1: 10 aqueous solution gives positive tests
REQUIREMENTS
for Acetate and for Sodium, Appendix IIIA.
Identification Dissolve about 1.5 g of sample in 10 mL of free acetic acid (CH3C00H), and not less than 58.0% an
d
water, add5 mL of2.7 Nhydrochloric acid, collect the crysials
not more than 60.0% of sodium acetate (CH3COONa),
with suction, wash with 10 mL of water, and dry between calculated on the anhydrous basis.
75 and 80 for 4 h. The crystals melt between 1090 and 111 Lead Nol more than 2 mg/kg.
(see Melting Range or Temperature, Appendix
IIB
Readily Oxidizable Substances (as form