Coal Liquefaction by Using Dielectric Barrier Discharge Plasma

An innovative method for coal liquefaction by using dielectric barrier discharge （DBD） plasma in a short reaction time was developed. Using tetralin as the reaction medium, DBD plasma as the energy source, and a reaction time of 10 min at 140 ℃, up to 10% of coal was converted to liquid material. The results showed the feasibility of coal＇s liquefaction by DBD plasma under relatively moderate conditions. Simultaneously, it was clarified that the effect of DBD plasma treatment was opposed to the thermal effect of heating. An acid plasma sheath could be formed on the coal powder surface in DBD conditions, liquefied reactions could be carried out in the absence of inorganic acid, and the products were nearly neutral and with low causticity.