ASTM D2320 Test Method for Density (Relative Density) of Solid Pitch (Pycnometer Method)
6. Apparatus
6.1 Glass Pycnometer, capacity about 25 mL, with accurately fitting glass stopper with a capillary tube 1.0 mm to 2.0 mm in diameter.

6.2 Water Bath, maintained at 25.0 °C +/- 0.1 °C and provided with mechanical stirring.

6.3 Vacuum Pump or Aspirator, capable of producing a vacuum of 2.7 kPa (20 torr).

NOTE 1 - 20 torr = 20 mm Hg = 2.66 kPa.

6.4 Manometer, suitable for measuring the specified vacuum.

6.5 Vacuum Desiccator with Guard.

6.6 Sieves, U.S. Standard 2.36 mm (No. 8) and 600 µm (No. 30) conforming to Specification E11.

7. Reagents and Materials
7.1 Wetting Agent, 0.1 g/mL Aerosol OT.

7.2 Wetting Agent, 0.1 g/mL BRU 35 (Alyoxyethylene dodecyl ether, detergent.

8. Bulk Sampling
8.1 Samples from shipments shall be taken in accordance with Practice D4296 and shall be free of foreign substances. Thoroughly mix the sample immediately before removing a representative portion for the determination or for dehydration.

9. Dehydration
9.1 All bulk samples suspected of having free moisture shall be air-dried or oven-dried at 50 °C in a forced-air oven before analyzing.

10. Preparation of Test Sample
10.1 Crush a 50 g to 100 g representative portion of the dry pitch until all of it passes through the 2.36 mm (No. 8) sieve. Avoid grinding the pitch. Remove the fines by screening through the 600 µm (No. 30) sieve and use the pitch retained on this sieve as the test sample. If desired, small lumps of pitch may be used without crushing, provided the lumps pass the 2.36 mm sieve and are retained on the 600 µm sieve. In either case, follow the evacuation steps described in 12.2. In case of dispute use the crushing method.

11. Calibration of Pycnometer
11.1 Weigh the thoroughly clean, dry, and assembled pycnometer to the nearest 0.5 mg and record the mass.

11.2 Fill the pycnometer with freshly boiled distilled water that has been cooled to about 20 °C. Insert the stopper with a rotary motion to secure a firm seat, making sure that no air is entrapped, then completely immerse the pycnometer in the water bath at 25 °C for a minimum of 30 min. Remove and wipe the filled pycnometer as described in 12.4; then immediately weigh to the nearest 0.5 mg. Remove the stopper and repeat the operations until three successive weighings agree within 0.5 mg. Record the average mass of the pycnometer with water.