ASTM D168 Standard Test Method for Coke Residue of Creosote
3. Summary of Test Method
3.1 After subjecting the creosote-coal tar solution (oil) under test to the distillation method (Standard A1, Section 2), the weighed residue at 355°C in the distillation flask is thoroughly mixed and a one-gram sample transferred to a special platinum crucible with vented cover. The crucible is then placed in a furnace maintained at 950 more or less 20°C for exactly 7 min. A final weighing gives the amount of coke of the distillation residue. The coke residue of the creosote-coal tar solution under test is calculated from (a) the percentage of distillation residue at 355°C, (b) the weight of the sample of distillation residue transferred to the platinum crucible, and (c) the weight of coke remaining in the platinum crucible after the coking operation.
4. Significance and Use
4.1 This test method is useful as an indicator of the preparation of coal tar in solution with coal tar distillate. The test method can also be used as one element in establishing uniformity of shipments and sources of supply.
