Adipic acid or hexanedioic acid is the organic compound with the formula (CH2)4(COOH)2. Adipic acid otherwise rarely occurs in nature, but it is known as manufactured E number food additive E355. Adipic acid has been incorporated into controlled-release formulation matrix tablets to obtain pH-independent release for both weakly basic and weakly acidic drugs. significant amounts of adipic acid are used as a food ingredient as a flavorant and gelling aid.

Specifications of Adipic Acid Commercial Pure

Appearance : It occurs as a white crystalline powder.
Melting point : Not less than 151.5 C
Moisture: Not more than 0.2%
Ammonia solution color (PT-CO): Not more than 5
Iron (Fe): Not more than 0.4 mg/kg
Nitric acid (HNO3): Not more than 3 mg/kg
Ashes : Not more than 4 mg/kg
Assay : Not less than 99.7%.

Adipic Acid USP NF Grade

C6H10O4 --- 146.1
Hexanedioic acid.
1,4-Butanedicarboxylic acid [124-04-9].
Adipic Acid contains not less than 99.0 percent and not more than 101.0 percent of C6H10O4, calculated on the dried basis.
Packaging and storage: Preserve in a tight container. No storage requirements specified.
Identification: Infrared Absorption 197K .
Melting range: between 151C and 154C.
Loss on drying: Dry it at 105C to constant weight: it loses not more than 0.2% of its weight.
Residue on ignition: not more than 0.1%.
Limit of nitrates: To pass the tt
Chloride: A 5-mL portion of the Test solution from the Limit of nitrates test shows no more chloride than a corresponding 0.14-mL portion of 0.020 N hydrochloric acid: the limit is 0.02%.
Sulfate: A 5-mL portion of the Test solution from the Limit of nitrates test shows no more sulfate than a corresponding 0.26-mL portion of 0.020 N sulfuric acid: the limit is 0.05%.
Iron: Use a 10-mL portion of the Test solution from the Limit of nitrates test: the limit is 0.001%.
Heavy metals: 0.001%.
Assay: Dissolve 60 mg of Adipic Acid in 50 mL of water. Add 0.2 mL of PhPh, and titrate with 0.1 N sodium hydroxide VS to a permanent pale pink endpoint. Each mL of 0.1 N sodium hydroxide is equivalent to 7.31 mg of C6H10O4.

Adipic Acid BP Grade

Ph Eur
C6H10O4 --- 146.1 --- 124-04-9
Action and use: Excipient.

DEFINITION

Hexanedioic acid.
Content: 99.0 per cent to 101.0 per cent (dried substance).

CHARACTERS

Appearance: White or almost white, crystalline powder.
Solubility: Sparingly soluble in water, soluble in boiling water, freely soluble in alcohol and in methanol, soluble in acetone.

IDENTIFICATION

A. Melting point (2.2.14): 151 °C to 154 °C.
B. Infrared absorption spectrophotometry.

TESTS

Solution S: Dissolve 5.0 g with heating in distilled water and dilute to 50 ml with the same solvent. Allow to cool and to crystallise. Filter through a sintered-glass filter (40). Wash the filter with distilled water. Collect the filtrate and the washings until a volume of 50 ml is obtained.
Appearance of solution: The solution is clear and colourless.
Dissolve 1.0 g in methanol R and dilute to 20 ml with the same solvent.
Related substances: Liquid chromatography To pass the test.
Chlorides: Maximum 200 ppm.
Nitrates: Maximum 30 ppm.
Sulphates: Maximum 500 ppm.
Iron: Maximum 10 ppm.
Heavy metals: Maximum 10 ppm.
Loss on drying: Maximum 0.2 per cent, determined on 1.000 g by drying in an oven at 105C.
Sulphated ash: Maximum 0.1 per cent.

ASSAY
Dissolve 60.0 mg in 50 ml of water. Add 0.2 ml of PhPh solution and titrate with 0.1 M sodium hydroxide. 1 ml of 0.1 M sodium hydroxide is equivalent to 7.31 mg of C6H10O4.

IMPURITIES

HO2C-R
A. R = CH2-CO2H: pentanedioic acid (glutaric acid),
B. R = CO2H: butanedioic acid (succinic acid),
C. R = [CH2]3-CO2H: heptanedioic acid (pimelic acid).

Adipic Acid FCC Food Grade

Hexanedioic Acid; 1,4-Butanedicarboxylic Acid
HOOC(CH2)4COOH
C6H10O4 Formula wt 146.14
INS: 355 CAS: [124-04-9]

DESCRIPTION

Adipic Acid occurs as white crystals or a crystalline powder. It is not hygroscopic. It is freely soluble in alcohol, soluble in acetone, and slightly soluble in water.
Function: Buffer; neutralizing agent.

REQUIREMENTS

Assay: Not less than 99.6% and not more than 101.0% of C6H10O4, calculated on the anhydrous basis.
Lead: Not more than 2 mg/kg.
Melting Range: Between 151.5° and 154°.
Residue on Ignition: Not more than 0.002%.
Water: Not more than 0.2%.