ASTM D4 Standard Test Method for Bitumen Content
3. Apparatus, Reagents, and Materials
3.1 Filtering Crucible, porcelain, high-form, 25 to 40-mL capacity, with fjine-porosity bottom, 7-µm maximum porosity.
3.2 Celite Analytical Filter Aid (CAFA), dried to constant mass at 105°C and stored in a tightly stoppered container.
3.3 Beakers - One 30-mL beaker, Griffin low-form, and one 150-mL beaker, Griffin low-form.
3.4 Carbon Disulfide, cp.
NOTE 1 - For filled asphaltic materials, trichloroethylene may be directly substituted for carbon disulfide if desired. However, carbon disulfide shall be used in referee testing.
3.5 Filtering Flask, with crucible adapter.
3.6 Drying Oven.
3.7 Bunsen Burner or Muffle Furnace.
3.8 Suction Pump.
3.9 Analytical Balance.
3.10 Desiccator.
3.11 Evaporating Dish.
3.12 Watch Glasses.
4. Safety Precautions
4.1 Carbon disulfide is extremely flammable. The vapor will often ignite spontaneously on contact with a hot surface such as a hot plate, oven, or radiator. When using this solvent, be sure that the filtration is conducted under a hood and well away from flame or other sources of heat. Before placing crucibles or other containers in the oven, all traces of carbon disulfide should be removed (as indicated by the disappearance of all odor). Otherwise, the vapors will ignite. Carbon disulfide is also very irritating to the skin and direct contact should be avoided.
5. Preparation of Sample
5.1 The sample shall be representative, and if it contains more than 2 % of water it shall be dehydrated in accordance with Test Method D370. If the material is hard and brittle, it may be ground and dried at a temperature below the temperature of volatilization of the material.
6. Crucible Preparation
6.1 If the crucible, after thorough cleaning (see 6.2), has been used for less than six determinations, clean it as follows: Remove the CAFA mat completely, wash the crucible with distilled water, dry, and ignite in a muffle furnace for 1 h at about 800°C. Cool the crucible slowly by placing it in a drying oven for 1 h after removal from the furnace to prevent cracking and place it in a desiccator while still warm.
6.2 After the crucible has been used for six determinations, remove any residual ash from pores in the filtering area by boiling in 1 + 1 hydrochloric acid. Then boil the crucible in distilled water, thoroughly back wash with distilled water, dry, and ignite as in 6.1.
