Solvothermal liquefaction of waste polyurethane using supercritical toluene in presence of noble metal catalysts
Vahab Ghalandari, Soudeh Banivaheb, Jessica Peterson, Hunter Smith, M. Toufiq Reza
Abstract
Abstract Solvothermal liquefaction (STL) is a thermochemical conversion method that uses sub‐or supercritical solvents to convert waste plastics like waste polyurethane (PU) into value‐added chemicals. This study aimed to evaluate catalytic STL utilizing toluene as a solvent for depolymerization of waste PU into valuable products. The effect of catalyst type (Pt/C, Pd/C, and Ru/C), catalyst loading (0–10 wt%), STL reaction temperature (330°C, 350°C, and 370°C), STL residence time (1, 3, and 5 h), and hydrogen loading (25, 50, and 75 bar) on STL conversion were studied. Results showed that Ru/C outperformed Pt/C and Pd/C and the STL conversion reached to as high as 87.2%. The concentrations of nitrogen‐containing components like aniline and p‐aminotoluene were increased with the increase of Ru/C loading and STL reaction temperature.