PROCEDURE FOR THE IDENTIFICATION OF EXPANDED CUT TOBACCO FALLING WITHIN TARIFF SUBHEADING 24.02 E OF THE COMMON CUSTOMS TARIFF
1. Principle
Expanded cut tobacco differs from non-expanded cut tobacco in that it is less dense.
2. Equipment
2.1. Chemicals:
Benzyl acetate, d = 1,055,
Ethyl acetate, d = 0,898;
2.2. Apparatus:
tall beaker, 1000 ml, graduated, diameter approximately 95 mm,
magnetic stirrer,
glass funnels, 15 cm diameter,
round filter (coarse), diameter approximately 270 mm,
glass Erlenmeyer flask, 1000 ml, wide-mouth,
set of watch glasses, diameter approximately 10 cm,
analytical balance (indication in g, to two decimal places),
drying cabinet.
3. Method
Fill a beaker to the 600 ml mark with benzyl acetate and place it on a vibration-free surface (e.g. a rigid table).
Dry about two g of tobacco to constant weight (for about three hours) in a drying cabinet at 85 °C (weighed-in portion = A). Determine in g, to two decimal places, the weight of the dried weighed-in portion.
Scatter the dried weighed-in portion (A) evenly over the surface of the liquid in the beaker and stir for 30 seconds with a magnetic stirrer.
Allow to stand for two minutes, transfer the supernatant into a round filter, rinse twice with 50 ml of ethyl acetate and dry to constant weight (for about three hours) in a drying cabinet at 85 °C (supernatant after drying = B). Determine in g, to two decimal places, the weight of the dried supernatant.
4. Calculation
Expanded tobacco % =
B × 100A
where
A = weighed-in portion in g to two decimal places,
B = supernatant in g to two decimal places.
The average result of at least two determinations must be taken into account.
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