---
title: "ASTM D5187"
url: "https://mat-cs.com/astm-d5187/"
description: "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."
---

ASTM Standard

# ASTM D5187

Standard Test Method for Determination of Crystallite Size (Lc) of Calcined Petroleum Coke by X-Ray Diffraction

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## Significance and Use

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

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

## Scope

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 (_La_) 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.