Transformation Characteristics of HydrogenDonor Solvent .
WEBNov 1, 2019 · Introduction. Direct liquefaction of coal is an effective measure for clean utilization of coal, which converts solid coal (H/C ratio ≈ ) to liquid fuels (H/C ratio ≈ 2) by adding hydrogen (Ren et al., 2010; Vasireddy et al., 2011).It is vital to provide enough hydrogen in a timely manner to stabilize free radicals from coal pyrolysis for getting .