Hydrocracking of Algae Oil and Model Alkane into Jet Fuel Using a Catalyst Containing Pt and Solid Acid

Aluminum polyoxocations were introduced into a lamellar zirconium phosphate (α-ZrP) via ion exchange. The Al polyoxocation pillars transformed into Al2O3 particles within the interlayer zone after calcination at 673 K. The resulting Al2O3-α-ZrP exhibited a large BET surface area and medium-strength acidity. Pt-supported Al2O3-α-ZrP was used as a catalyst for hydrocracking squalene and Botryococcus braunii oil in an autoclave batch system. In a one-step squalene hydrocracking process, the yield of jet-fuel-range hydrocarbons was 52.8% on 1 wt.% Pt/Al2O3-α-ZrP under 2 MPa H2 at 623 K for 3 h. A two-step process was designed with the first step at 523 K for 1 h and the second at 623 K for 3 h. During the first step, the squalene was hydrogenated to squalane without cracking, and in the second step, the squalane was hydrocracked. This two-step catalytic process increased the yield of jet-fuel-range hydrocarbons to 65% in squalene hydrocracking. For algae oil hydrocracking, the jet-fuel-range hydrocarbons occupied 66% of the total products in the two-step reaction. Impurities in algae oil, mainly fatty acids, did not affect the yield of jet-fuel-range hydrocarbons because they were deoxygenated into hydrocarbons during the reaction. The activity of Pt/Al2O3-α-ZrP remained unchanged after four reuses through simple filtration.