Jatropha Curcas seed oil and biofuels

Jatropha curcas is a potential source of hydrocarbons that have created interest all over the world for the use of its seed oil as a commercial source of fuel. The oil contains mainly oleic (37-63%) as principal fatty acid unlike other Jatropha species, which show predominance of linoleic acid. Jatropha can supply raw materials for biodiesel production and can chance marginal lands into valuable economic lands. Biohydrogenated diesel is called the second generation bio-diesel and it is produced by the hydrotreatment of triglycerides can convert vegetables oil to biofuels liquids products, such as green naphtha (C₅-C₁₀), green jet fuel (C₁₁-C₁₃), and green diesel (C₁₄-C₂₀). During hydroprocessing of triglycerides, the type of catalyst is one of the most important factors to determine the yield and composition for all unsaturated C = C double bonds have been hydrogenated and the oxygen atoms have been removed in the hydrotreatment process. Tree types of catalysts have been reported for the hydrotreatment process: noble metal catalysts (Pd, Pt, etc.), desulfurized catalysts (Ni-Mo, Co-Mo, Ni-W, Co-W, etc.) and solid acid catalysts (such as H-ZSM-5, SO₄/ZrO₂, etc.) Although C₁₈, C₁₇, C₁₆, and C₁₅ are the main products over all catalysts, the amount of light hydrocarbons (≤ C14) formed increased when the reaction temperature increased from 300 to 400°C. At these conditions, occur a cracking of normal paraffins caused the increase of light hydrocarbons (≤ C₁₄) at high reaction temperatures. Recently, the production of biohydrogenated diesel by the hydrotreatment of Jatropha curcas seed oil over Ni-Mo based catalysts in a high pressure fixed bed flow reactor system at 350°C under 4 MPa of hydrogen. Jatropha curcas L. oil was converted into paraffins by one-step hydrotreatment process. Ni-Mo/SiO₂ catalyst favored the production of C₁₈, to C₁₅. These long normal hydrocarbons have a high melting point and thus the liquid hydrocarbon product has poor cold properties. The use of Ni-Mo supported on zeolites, i.e., Ni-Mo/HY or Ni-Mo/H-ZSM₅, USY/Al₂O₃ resulted in the production of a large amount of gasoline hydrocarbons. Considering the problem of biofuels competing with food sources, non-edible plant oil as Jatropha curcas seed oil have the potential to be used as feedstock to produce green diesel for the transportation fuel.