The role of donatable hydrogen and gaseous hydrogen in the NEDOL process was investigated with a 51 batch-autoclave.
The following conclusions are obtained.
(1) Both donatable hydrogen in the recycle solvent of lt/d Process Support Unit (PSU) and gaseous hydrogen contribute to the coal liquefaction reaction. The donatable hydrogen is superior because it largely promotes liquid-phase reaction.
(2) The hydrocracking reaction of the recycle solvent occures under coal liquefaction conditions, and gaseous hydrogen is transferred to the recycle solvent.
(3) Severe conditions in the solvent hydrogenation reaction are needed in order to make use of hydrogen effectively and obtain high oil yield.
