Nonsolvent coal hydrogenation at short contact time

Yields and properties of products on hydrogenation of Japanese and Australian coals have been studied using an autoclave equipped with a magnedrive device at temperatures of 500–600 °C and hydrogen pressure 4.9–14.7 MPa (gauge) in the absence of solvent. Optimum contact time, at which maximum extraction yield was observed, shifted from 15 s to a few seconds with increasing reaction temperature and hydrogen pressure. The extracts derived from both coals reveal similar structural parameters.