Liquefaction of bislig and Bicol coals using an autoclave.

Liquefaction is one of the latest ways of harnessing useful products from coal, and it is also widley considered as one of the best methods for converting coals into more useful liquid products. The liquefaction of Bislig and Bicol coals via hydrogenation was studied in an autoclave under relatively high temperatures and pressures. Solvents such as water and ethanol were used. Temperatures used range between 300 and 350 centigrade and operating pressures were between 1000 to 1500 psig. The effect of adding pure hydrogen gas with water as solvent and the effect of the amount of water solvent were also studied. The study showed that more coals were converted into products at higher temperatures and when larger amounts of solvents were used. Furthermore, water appears to give larger liquid yields compared with ethanol. The adding of pure hydrogen gas had greater effects on the liquefaction of Bicol coals, but an increase in hydrogen pressure did not show any appreciable change in the liquefaction process