Co‐Pyrolytic Recycling of Bakelite and Polymethyl Methacrylate: Kinetic, Synergistic, and Thermodynamic Analysis

Abstract Bakelite, a thermosetting plastic, has limited feasibility for thermal recycling processes such as pyrolysis, unlike thermoplastics, due to its inherent tendency to get charred upon heating and difficulty in being converted into valuable fuel and chemical compounds. In this study, the co‐pyrolysis of bakelite and poly methyl methacrylate is explored to improve the thermal degradation and thus recycling feasibility of bakelite by pyrolysis. The kinetics and thermodynamics of the co‐pyrolysis of blended samples are analyzed using different kinetics models. The thermal degradation experiments of the sample are conducted from ambient to 1000 °C at five various heating rates of 5, 10, 20, 30, and 50 °C/min in an inert N 2 gas environment. The results showed that adding poly methyl methacrylate to bakelite changes the pyrolytic degradation temperature and weight loss trend. The kinetic analysis reveals that the thermal degradation at 220–345 °C follows an F 2.5 order‐based model with an average activation energy of 181 kJ/mol, while the degradation at 345–475 °C follows an F 2 order‐based model with an average activation energy of 318 kJ/mol. The enthalpy changes and free energy change associated with thermal degradation exhibit a positive trend while that of entropy change shows a negative trend. With blending the free energy change and entropy change decreased while enthalpy change increased. During batch pyrolysis at 450 °C, the PMMA‐Bakelite blend generates oil (49.17 %), wax (12.36 %), residue (15.36 %), and gas (23.11 %). According to FTIR and GC‐MS analyses, the pyrolytic oil produced by the co‐pyrolysis of the blended sample at 450 °C comprises 32.23 % saturated hydrocarbons (C 9–40 ), 20.97 % unsaturated hydrocarbons (C 6–24 ), and 46.80 % oxygenated material (C 5–19 ). These findings can assist in the optimization of pyrolysis reactor design for the recycling of thermosetting plastics.