Study of coke by X-ray structural analysis and scanning electron microscopy

Abstract

In this work, a number of industrial samples of needle cokes from various manufacturers were studied. The study of the samples was carried out by methods of X-ray diffractometry and analytical scanning electron microscopy. The parameters of their crystal structure were determined, and the features of their microstructure were investigated. The differences found in the crystal structure and morphology of coke particles made it possible to divide the studied samples into 2 groups: isotropic, with equal longitudinal and transverse crystallite sizes, and anisotropic, in which the longitudinal crystallite sizes exceed the transverse ones by 3-4 times. Particles of isotropic cokes have a fracture texture characteristic of a glassy amorphous body, in contrast to which particles of anisotropic cokes have a lamellar texture. The consistency of the conclusions obtained from the results of two independent methods makes it possible to consider X-ray diffraction analysis in combination with analytical electron microscopy as the necessary complementary tools for evaluating cokes with the aim of their possible application in various technological processes.