Energy & Fuels, Vol.21, No.3, 1425-1431, 2007
Low-pressure hydrocracking of coal-derived Fischer-Tropsch waxes to diesel
Coal-derived low-temperature Fischer-Tropsch (LTFT) wax was hydrocracked at pressures of 3.5-7.0 MPa using silica-alumina-supported sulfided NiW/NiMo and an unsulfided noble metal catalyst, modified with MoO3. A low-pressure operation at 3.5 MPa produced a highly isomerized diesel, having low cloud points (from -12 to -28 degrees C) combined with high cetane numbers (69-73). These properties together with the extremely low sulfur (< 5 ppm) and aromatic (< 0.5%) contents place coal/liquid (CTL) derived distillates as highly valuable blending components to achieve Eurograde diesel specifications. The upgrading of coal-based LTFT waxes through hydrocracking to high-quality diesel fuel blend components in combination with commercial-feasible coal-integrated gasification combined cycle (coal-IGCC) CO2 capture and storage schemes should make CTL technology more attractive.