10.水熱処理を行った低炭化度炭の表面変化と改質助剤の影響

抄録

Properties of low-rank coals when the coal was hydrothermally-treated at 150-350℃ were examined with particular emphasis on the surface properties. The analysis of coal properties includes, hygroscopicity, the contents of carboxyl group and phenolic hydroxyl group, specific surface area, atomic force microscope (AMF) imaging, and maceral composition. The content of carboxyl group greatly decreased as heat-treatment temperature (HTT) was raised; whereas decrease in the content of hydroxyl group was rather small. When the hydrothermal treatment was performed in the presence of an upgrading agent, such as tall oil, the hygroscopicity of 200℃ treated coal was comparable to that for a coal treated at 300℃ without the agent.