Catalytic Co-Pyrolysis of Kraft Lignin with Refuse-Derived Fuels Using Ni-Loaded ZSM-5 Type Catalysts

The catalytic co-pyrolysis (CCP) of Kraft lignin (KL) with refuse-derived fuels (RDF) over HZSM-5, Ni/HZSM-5, and NiDHZSM-5 (Ni/desilicated HZSM-5) was carried out using pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) to determine the effects of the nickel loading, desilication of HZSM-5, and co-pyrolysis of KL with RDF. The catalysts were characterized by Brunauer⁻Emmett⁻Teller surface area, X-ray diffraction, and NH3-temperature programed desorption. The nickel-impregnated catalyst improved the catalytic upgrading efficiency and increased the aromatic hydrocarbon production. Compared to KL, the catalytic pyrolysis of RDF produced larger amounts of aromatic hydrocarbons due to the higher H/Ceff ratio. The CCP of KL with RDF enhanced the production of aromatic hydrocarbons by the synergistic effect of hydrogen rich feedstock co-feeding. In particular, Ni/DHZSM-5 showed higher aromatic hydrocarbon formation owing to its higher acidity and mesoporosity.