Carbonization properties of carbonaceous substances oxidized by air blowing-I. Carbonization behaviors and chemical structure of residual oils oxidized by air blowing

The carbonization process of oxidized oils was investigated by the successive observation of the cokes at several intermediate stages with particular attention to the cocarbonization compatibility of the components, in order to understand how the medium mosaic texture was developed from the oxidized oils. When the oxidized oil was carbonized, very small anisotropic spheres appeared in the matrix, but, being fixed into the mosaic texture, they formed clusters with limited growth of their diameters. The n-hexane insoluble (nHI) and the n-hexane soluble (nHS) components in the, oxidized oil produced isotropic and flow textures in the cokes, respectively. These components did not allow the smooth growth of the anisotropic spheres because of their poor compatibility. Cocarbonization with some proper additives was found effective both in developing a flow texture from the nHI of the oxidized oil and producing a high coke yield. Chemical analyses of the components were performed in order to explain the compatibility.