Gasification reactivities of optical textures of metallurgical cokes

Optical textures of ten typical cokes before and after gasification in CO2 were quantified by point counting under a polarized microscope to quantify the reactivities of each type of optical texture. Although absolute values of gasification rate for each texture varied considerably from coke to coke, their relative values were constant regardless of the origin of the cokes. The relative reactivities of flow, mosaic, isotropic and inert textures were 1,1.8,2.8 and 3.0, respectively. The relative reactivity of a single coke calculated from a knowledge of optical textures, was monotonicly correlated with the mean maximum reflectance (R̄0) of the parent coal. This indicates that the high reactivity of coke from a high-rank coal (r̄0 = 1.8%) is due to factors other than its optical texture. The crystallite height, Lc(002)' of the coke correlated with R̄0 of the parent coal, although the values of Lc(002) varied only from 1.5 to 2.1 nm.