Analysis of carbon structure in cokes at molecular level

The quality of coke strongly depends on their carbon structure, but so far most of the researches for the microscopic analysis of cokes structure have been conducted at optical-microscopic level. It is essentially important to understand carbon structure in cokes from molecular point of view. In this study, several types of cokes have been analyzed with several means such as X-ray diffraction, transmission electron microscopic observation and temperature programmed desorption, all of which have been utilized to understand the molecular structure of the cokes. From the results thus obtained, it was found that the structural difference at molecular level between the cokes from caking and slightly caking coals is not so remarkable as one expected. However, there is a small but distinct difference between the two types of cokes. This study demonstrates that the use of several analysis techniques gives different views of coke structure and they are quite useful for the understanding of the carbon molecular structures.