ASTM D4893 Standard Test Method for Determination of Pitch Volatility
5. Dehydration of Sample
5.1 Hard Pitch - If the solid bulk sample contains free water, air-dry a representative portion in a forced-draft oven at 50°C (122°F).
5.2 Soft Pitch (Softening Point <60°C (<140°F)) - If the presence of water is indicated by surface foam on heating, maintain a representative portion of the bulk sample at a temperature between 125 and 150°C (251 and 302°F) in an open container until the surface is free of foam. Take care not to overheat, and remove heat source immediately when foam subsides.
6. Preparation of Working Sample
6.1 Crush sample to pass No. 4 mesh (4760 µm).
7. Preparation of Apparatus
7.1 Assemble the apparatus so that the exit opening in the upper block is aligned with bottom nitrogen inlet fitting of the bottom block. Both top and bottom blocks are heated to the test temperature, 350°C (662°F), using the proportional temperature controllers. Avoid heating the upper block and lower block when separated from each other.
