Investigation of the production of high cetane number bio gas oil from pre-hydrogenated vegetable oils over Pt/HZSM-22/Al2O3

A new field of the catalytic application of Pt/HZSM-22/Al2O3 catalysts for the isomerization of pre-hydrogenated sunflower oils (PHSO) aiming the production of diesel fuel is presented. High cetane number blending components that are practically free of sulfur (<1 ppm) and of aromatic compounds are required for satisfying environmental and human health regulations as well as specifications of diesel fuels in the European Union (cetane number: min 51; CFPP: max −20 °C depending on the climate of the country). Experiments were carried out over catalysts containing 0.25–1.1% platinum on HZSM-22 at temperatures of 280–370 °C, total pressures of 35–80 bar; liquid hourly space velocities (LHSV) of 1.0–4.0 h−1, H2 to hydrocarbon ratios of 250–400 Nm3/m3. Results indicated that the yield of liquid products obtained under favorable process conditions was >90%, the ratio of i-/n-paraffins was in the range of 3.7:1–4.7:1, cetane numbers were 81–84 units and CFPP values were between −18 and −14 °C. These are excellent blend stocks of diesel fuels.