Development of Ordered Structures in the High-Temperature (HT) Cokes from Binary and Ternary Coal Blends Studied by Means of X-ray Diffraction and Raman Spectroscopy

The aim of this work was to characterize ordered structures within cokes produced from single bituminous coals and from their blends. Three Polish coals of varying rank and caking ability were collected from the Krupinski, Szczyglowice, and Zofiowka mines, respectively. These coals were used for preparation of 19 blends: single (trivial blends), binary, and ternary ones. Cokes were manufactured in a laboratory scale using an apparatus with a Jenkner’s retort with a charge of 1000 g and heat-treatment temperature of 1000 °C. The X-ray diffraction (XRD) and Raman spectroscopy were used for the study. To determine the kind and size of ordered structures, the following parameters were discussed: interlayer spacing, d002, crystallite stack height, Lc, obtained from the XRD studies as well as the fractional contribution of ordered elements to all kinds of structures, and ratio of the amount of graphite structures (G type) to the amount of D2-type structures (less ordered than graphite), determined with Raman sp...