Catalytic hydrotreating of algae bio-crude oil from hydrothermal liquefaction (HTL) Nannochloropsis sp. was performed. Different Ni-based catalysts, including Ni/γ-Al2O3, Ni-Cu/γ-Al2O3, Ni-Re/γ-Al2O3, and Ni-Cu-Re/γ-Al2O3, (10%Ni, 5%Cu, 2.5%Re) were used in upgrading the oil. Most catalytic systems could effectively eliminate S decrease N O contents, enhance more than 20% improvement higher hea...