Catalytic liquefaction of human feces over Ni-Tm/TiO2 catalyst and the influence of operating conditions on products

•Catalytic liquefaction could convert 89.77% of human feces.•The highest biocrude yield was 53.16% with Ni-Tm/TiO2 catalyst.•Catalyst, temperautre and time significantly influenced the biocrude composition.•The distribution of gaseous products at different HTL conditions were analyzed. In this study, human feces were hydrothermal liquefied and converted into biocrude over Ni-Tm/TiO2 catalyst. The influence of catalysts, reaction temperature, and holding time on the distribution of products and element content of biocrude was assessed. The biocrude yield increased to 53.16% with a reaction temperature of 330 °C, a holding time of 30 min, and adding Ni-Tm/TiO2 catalyst while the liquefaction conversion peaked at 89.61%. The biocrude had an HHV of 36.64 MJ/kg and was similar to heavy crude oil. The biocrude is rich in fatty acid amides, esters, and oxygen-containing-only heteroatom-ring compounds as well as some nitrogen-containing heteroatom-ring compounds. The main gaseous products were CO2, CH4, and C2H6. Hydrothermal liquefaction over Ni-Tm/TiO2 catalyst could be a potential method to handle human excrement treatment and produce biofuel.