Effect of Carbonization and NaOH Solution on Characterization PET Waste Activated Carbon

PET plastic waste threatens the environment and health because it is difficult to decompose and should not be burned carelessly. The accumulation of such waste requires a 3R solution (reduce, reuse, recycle). A new method is offered to recycle PET waste into activated carbon. This study aims to investigate the properties of carbon derived from the carbonization of PET waste at temperatures of 300 °C, 400 °C, and 500 °C. The resulting carbon was activated by a chemical activation method with NaOH as the activator at concentrations of 0.5 Mole, 1.5 Mole, and 3 Mole. The physicochemical properties of the activated carbon were analyzed using X-Ray Diffraction (XRD) and Fourier-Transform Infrared (FTIR) spectroscopy. The recycling process includes carbonization stage, chemical activation stage and ends with physical activation through heating. PET was successfully converted into carbon at 400 °C. The carbonization results showed an efficiency of up to 18%. XRD results showed two compounds detected at this highest peak, namely tetramethylammonium nitrate (C4H12N2O3) and urea (CH4N2O). In addition, the activation of carbon with NaOH solution was seen to form an amorphous structure characterized by a widened peak that increased with increasing NaOH solution. Interpretation of the FTIR spectrum of activated carbon with a concentration of 3 Mole shows a peak at 3246 cm-1 indicating the presence of hydroxyl groups (-OH) or N-H bonds, a peak at 2361 cm-1 associated with stretching C≡N (nitrile) or CO₂, a peak at 2092 cm-1 indicating the presence of C≡C bonds or higher carbon-carbon bonds. This method can be a reference for recycling PET waste into activated carbon materials.