The present paper deals with the solvolysis reaction of coal with petroleum vacuum residue. Various kinds of coal samples (C: 66.3-90.1%) were examined, and Khafji vacuum residue was used as a solvent.
Coal powder was mixed with Khafji vacuum residue, and the mixture was heattreated (350-430°C) for several hours. During the heat-treatment, a considerable amount of gas and oil evolved, and pitch-like meterial (hereafter we call solvolysis pitch) was resided. After heat-treatment, the solvolysis pitch was extracted with ordinaly kinds of organic solvent, such as quinoline, pyridine. The following conclusions can be drawn by present study.
(1) Coal can be solubilized through the solvolysis reaction with the petroleum vacuum residue.
(2) In the case of Miike Coal (C: 82.9%), the amounts of quinoline insolble matter reach a minimum at 390°C for the solvolysis pitch obtained from a mixture of one part of coal and two parts of the petroleum residue. Miike coal can be almost solubilized when heat-treated with the equal weight of petroleum residue at 390°C.
(3) Pittsburg coal (C: 81.4%) and Miike coal were found to be most suitable ones among the coals examined for solvolysis.
(4) Micrographic textures of the solvolysis pitches are strongly dependent on the carbon content of coal used.
