Catalytic co-pyrolysis of epoxy-printed circuit board and plastics over HZSM-5 and HY

The catalytic co-pyrolysis of epoxy-printed circuit board (e-PCB) and thermoplastics, high density polyethylene (HDPE) and polypropylene (PP), over HZSM-5 and HY was performed using a thermogravimetric analyzer and pyrolyzer-gas chromatography/mass spectrometry. The catalytic pyrolysis of e-PCB over both HZSM-5 and HY eliminated the brominated compounds, mainly bromo-phenols and -bisphenol As, to some extent. The co-feeding of HDPE and PP on the catalytic pyrolysis of e-PCB over both HZSM-5 and HY revealed different debromination efficiencies due to the properties of the thermoplastics and catalysts. A comparison of HY(80) and HZSM-5(80) with the same SiO₂/Al₂O₃ ratio (80) revealed HY(80) had a better elimination efficiency of brominated compounds during the catalytic co-pyrolysis of e-PCB and HDPE or PP because of its larger pore size than HZSM-5(80). The lowest bromine content was achieved when HDPE and HY(30) were used as the co-feeding reactant and catalyst on the pyrolysis of e-PCB due to the large pore size and high acidity of HY(30), allowing the easier diffusion of large molecular brominated bisphenol A and HDPE molecules into the pores of the catalyst and efficient catalytic intermolecular reactions in the pores of the catalyst. The catalytic co-pyrolysis of e-PCB and HDPE over HY(30) also produced large amounts of mono-aromatic hydrocarbons and mono-phenol, which can be used as fuels or chemical feedstock.