Apricot Kernel Water
Apricot Kernel Water contains
not less than 0.09 w/vz and not more than 0.11 w/vz of hydrogen cyanide (HCN:
27.03).
Method of preparation:
Prepare by one of the following
methods.
(1) To Apricot Kernels, previously crushed and pressed to remove
fixed oils as much as possible, add a suitable amount of Water, Purified Water
or Purified Water in Containers, and carry out steam distillation. Determine
the amount of hydrogen cyanide in the distillate by the method as directed in
the Assay, and carry on the distillation until the content of hydrogen cyanide
in the distillate is about 0.14 w/vz. To the distillate add Ethanol in about
1/3 of the volume of the distillate, and dilute with a mixture of Purified
Water or Purified Water in
Containers and Ethanol (3:1) until the content of hydrogen cyanide meets the
specification.
(2) Dissolve 7.5 mL of freshly prepared mandelonitrile in 1000 mL
of a mixture of Purified Water or Purified Water in Containers and Ethanol (3:1),
mix well, and filter. Determine the amount of hydrogen cyanide in the solution
as directed in the Assay, and, if the amount is more than that specified above,
dilute the solution to the specified concentration by the addition of the
mixture of Purified Water or Purified Water in Containers and Ethanol (3:1).
Description:
Apricot Kernel Water is a
clear, colorless or pale yellow liquid. It has an odor of benzaldehyde and a characteristic
taste.
pH: 3.5 . 5.0
Identification:
To 2 mL of Apricot Kernel Water
add 1 mL of ammonia TS, and allow to stand for 10 minutes: a slight turbidity
is produced. Allow to stand for 20 minutes: the turbidity is intensified.
Specific gravity d2020:
0.968-0.978
Purity:
(1) Sulfate. Add a few drops of 0.1 mol/L sodium hydroxide VS to
5.0 mL of Apricot Kernel Water to make slightly alkaline, evaporate on a water
bath to dryness, and ignite between 4500C and 5500C.
Dissolve the residue in 1.0 mL of dilute hydrochloric acid, and add water to
make 50 mL. Perform the test using this solution as the test solution. Prepare
the control solution with 0.50 mL of 0.005 mol/L sulfuric acid VS (not more
than 0.005z).
(2) Heavy metals <1.07>.Evaporate 50 mL of
Apricot Kernel Water on a water bath to dryness, ignite between 4500C
and 5500C, dissolve the residue in 5 mL of dilute acetic acid with
warming, add water to make exactly 50 mL, and filter. Remove the first 10 mL of
the filtrate, dilute the subsequent 20 mL to 50 mL with water, and perform the
test using this solution as the test solution. Prepare the control solution as
follows: to 2.0 mL of Standard Lead Solution add 2 mL of dilute acetic acid and
water to make 50 mL (not more than 1 ppm).
(3) Free hydrogen cyanide.To 10 mL of Apricot Kernel Water add 0.8
mL of 0.1 mol/L silver nitrate VS and 2 to 3 drops of nitric acid at 159C,
filter, and add 0.1 mol/L silver nitrate VS to the filtrate: no change occurs.
(4) Residue on evaporation.Evaporate 5.0 mL of Apricot Kernel Water
to dryness, and dry the residue at
1050C for 1 hour:
the mass of the residue is not more than 1.0 mg.
Assay:
Measure exactly 25 mL of
Apricot Kernel Water, add 100 mL of water, 2 mL of potassium iodide TS and 1 mL
of ammonia TS, and titrate with
0.1 mol/L silver nitrate VS until a yellow turbidity persists.
Each mL of 0.1 mol/L silver
nitrate VS ＝ 5.405 mg of HCN
Containers and storage:
Containers. Tight containers.
Storage.Light-resistant.
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