The crystallinity of petroleum coke, as reflected by the L_c value, is a general measure of quality affecting suitability for end use and is a function of the heat treatment.

The crystallite thickness is used to determine the extent of such heat treatment, for example, during calcination. The value of the L_c determined is not affected by coke microporosity or the presence of foreign, non-crystalline materials such as dedust oil.

1.1 This test method covers the determination of the mean crystallite thickness of a representative, pulverized sample of calcined petroleum coke by interpretation of a X-ray diffraction pattern produced through conventional X-ray scanning techniques.

1.2 Calcined petroleum coke contains crystallites of different thicknesses. This test method covers the determination of the average thickness of all crystallites in the sample by empirical interpretation of the X-ray diffraction pattern. The crystallite diameter (L_a) is not determined by this test method.

1.3 The values stated in SI (metric) units are to be regarded as the standard. The inch-pound units given in parentheses are provided for information purposes only.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.