ASTM D1342-92(1996)
(Test Method)Standard Test Method for Paraffin-Type Hydrocarbons in Carnauba Wax
Standard Test Method for Paraffin-Type Hydrocarbons in Carnauba Wax
SCOPE
1.1 This test method covers the determination, by chromatography, of paraffin-type hydrocarbons in carnauba wax.
1.2 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. >
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Standards Content (Sample)
Designation: D 1342 – 92 (Reapproved 1996)
Standard Test Method for
Paraffin-Type Hydrocarbons in Carnauba Wax
This standard is issued under the fixed designation D 1342; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 6. Procedure
1.1 This test method covers the determination, by chroma- 6.1 Place a wad of glass wool in the bottom of the
tography, of paraffin-type hydrocarbons in carnauba wax. separatory funnel and pour 220 to 225 g of alumina on top of
1.2 This standard does not purport to address all of the this plug. Tap the side of the funnel sharply several times with
safety concerns, if any, associated with its use. It is the the palm of the hand in order to pack the alumina evenly, and
responsibility of the user of this standard to establish appro- then cover the adsorbent with a thin layer of glass wool.
priate safety and health practices and determine the applica- Immediately warm the column by pouring 400 mL of heptane
bility of regulatory limitations prior to use. at its boiling point through the adsorbent with the stopcock
adjusted to permit maximum flow of the solvent. Tap the
2. Referenced Documents
column to remove entrained air. Close the stopcock after the
2.1 ASTM Standards: last of the heptane has been added and while a layer about 10
D 94 Test Method for Saponification Number of Petroleum
mm deep still remains above the surface of the alumina.
Products 6.2 Dissolve 4.0 to 4.5 g of the sample, weighed to the
nearest 0.01 g, in 700 mL of boiling heptane in a 1-L, tallform
3. Significance and Use
beaker. Pour the solution quantitatively onto the warm column
3.1 This test method is used to determine the natural or
of alumina. Collect the percolate in a beaker placed under the
added hydrocarbon component of carnauba. It is used for
funnel with the stopcock in a position to permit maximum flow
quality control or to assess adulteration.
through the column. Maintain the temperature of the solution
being added and the column at approximately the boiling point
4. Apparatus
of heptane throughout the course of the addition. The tempera-
4.1 Cylindrical Separatory Funnel, 250-mL capacity, hav-
ture of the percolate issuing from the funnel stem shall be at 50
ing an open top.
to 55°C. After the last of the solution has been added, rinse the
4.2 Analytical Balance, having a sensitivity of 0.1 mg.
tall-form beaker with two successive 50-mL portions of fresh,
4.3 Electric Hot Plate.
boiling heptane and add the washings to the column. At this
4.4 Electric Oven, capable of maintaining a temperature of
stage a yellow band, which should not extend more than about
100 6 5°C.
40 mm down from the top of the alumina, will have developed.
A wider band than this probably indicates that the column was
5. Reagents
not packed properly. In such a case it may be difficult to effect
5.1 Alumina, having an activity of II according to the
a clean separation of the hydrocarbons in one pass through the
Brockmann classification. Since alumina of an activity of I
alumina.
according to the classification also has been found to be
6.3 Elute the column with additional heptane at within 5°C
satisfactory for the separation, any alumina falling in the
of its boiling point and, when about 1 L of percolate has been
activity range from I to II is suitable for use in this test method.
obtained, begin to test subsequent portions of the percolate for
The alumina must be kept free from moisture to retain its
complete elution of the hydrocarbons. To do this, collect
adsorptive properties.
50-mL portions of the percolate in separate 100-mL beakers,
5.2 Heptane, technical grade.
evaporate the solvent on the hot plate, and allow the beakers to
cool to room
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