Carnauba Wax
DEFINITION
Carnauba Wax is obtained from the leaves of Copernicia cerifera Mart. (Fam. Palmae).
IMPURITIES
• Residue on Ignition 281
Sample:
2 g
Analysis:
Heat the Sample in an open porcelain or platinum dish over a flame: it volatilizes without emitting an acrid odor. Ignite.
Acceptance criteria:
The weight of the residue is NMT 5 mg, corresponding to NMT 0.25%.
• Heavy Metals, Method II 231:
20 ppm
SPECIFIC TESTS
• Acid Value
Sample:
3 g
Analysis:
Weigh the Sample into a 250-mL flask attached to a reflux condenser. Add 50 mL of a mixture of isopropyl alcohol and toluene (5:4), and boil gently until the wax is completely dissolved. Remove the flask from the condenser, add 1 mL of phenolphthalein TS, and immediately titrate with 0.5 N alcoholic potassium hydroxide VS to a faint, reddish-yellow color. [NoteDo not allow the solution to cool. Titrate at warm temperature after refluxing. ]
Calculate the acid value as the number of mg of potassium hydroxide required to neutralize the free acids in 1 g of Carnauba Wax.
Acceptance criteria:
27
• Fats and Fixed Oils, Saponification Value 401
Sample:
Use the solution from the test for Acid Value.
Analysis:
To the Sample add 15.0 mL of 0.5 N alcoholic potassium hydroxide VS, reflux for 3 h, and titrate the excess alkali with 0.5 N hydrochloric acid VS to a yellow-amber color. Perform a blank determination (see Titrimetry 541, Residual Titrations).
Calculate the ester value. The saponification value is the sum of the ester value and the acid value.
Acceptance criteria:
7895
ADDITIONAL REQUIREMENTS
• Packaging and Storage:
Preserve in well-closed containers.
Auxiliary Information
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USP35NF30 Page 2015
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