Kinetic Analysis and Products Characterization of Hydrothermal Liquefaction of Tetra Pak Waste for Bio-Oil Production.

Hydrothermal liquefaction (HTL) of Tetra Pak waste was investigated at 320-440 °C for 10-50 min to produce bio-crude oil. Bio-oil yield increased with temperature and time, reaching about 43 wt% at 40-50 min, while solid residue decreased and stabilized. Boiling point analysis indicated diesel- and kerosene-range fractions as dominant components. FT-IR results showed enhanced aromatic and carbonyl groups with reaction time, suggesting secondary condensation. A modified first-order kinetic model described the conversion of carbohydrates and polyethylene, with activation energies of 25.8-49.0 and 54.9-78.3 kJ mol-1, respectively. The intermediate aqueous/gaseous pathway exhibited a lower activation energy (30.1 kJ mol-1), highlighting its vital role in oil formation. This study advances understanding of Tetra Pak liquefaction and provides guidance for efficient composite waste valorization.