Production of hydrogen and valuable fuels from polyethylene terephthalate waste dissolved in phenol reforming and cracking reactions via Ni-Co/CeO2 nano-catalyst

Abstract

This research investigates the preparation of Ni-Co/CeO2 catalysts based on impregnation and hydrothermal treatment methods for the hydrogen and valuable fuels generation from the steam reforming and cracking reactions of polyethylene terephthalate (PET) waste liquefied in phenol. PET plastic waste is environmentally harmful, mostly when it eliminated by burning or landfilling. Therefore, in this study, this waste has been dissolved in phenol for hydrogen and liquid fuel generation via catalytic steam reforming and cracking reactions. Complementary characterization techniques such as XRD, BET, FTIR, SEM, TEM, EDX, H2-TPR, CO2-TPD, NH3-TPD, ICP, CHNS and TGA were used to correlate surface structure and functionality to catalytic performance of the catalysts. The hydrothermal route leads to higher catalyst activity and stability against a by-product formation such as coke, which approved by time on stream process, TGA and CHNS analysis. For an instant, at 700 °C of the catalytic reaction, impregnation method cause to achieve 72.8 % of phenol conversion and 56 % of hydrogen yield, while these factors increased when conducting the hydrothermal treatment to 83.8 % and 76 %, respectively. Analysis of liquid products obtained from GCMS illustrated that valuable components such as dibenzofuran, 2-methyl phenol and benzene were produced from PET cracking and phenol steam reforming reactions. This phenomenon is a vital idea to solve plastic waste recycling issues.