Upgrading Mixed Agricultural Plastic and Lignocellulosic Waste to Liquid Fuels by Catalytic Pyrolysis

Agriculture generates non-recyclable mixed waste streams, such as plastic (netting, twine, and film) and lignocellulosic residues (bluegrass straw/chaff), which are currently disposed of by burning or landfilling. Thermochemical conversion technologies of agricultural mixed waste (AMW) are an option to upcycle this waste into transportation fuel. In this work, AMW was homogenized by compounding in a twin-screw extruder and the material was characterized by chemical and thermal analyses. The homogenized AMW was thermally and catalytically pyrolyzed (500-600 degrees C) in a tube batch reactor, and the products, including gas, liquid, and char, were characterized using a combination of FTIR, GC-MS, and ESI-MS. Thermal pyrolysis wax products were mainly a mixture of straight-chain hydrocarbons C-7 to C-44 and oxygenated compounds. Catalytic pyrolysis using zeolite Y afforded liquid products comprised of short-chain hydrocarbons and aromatics C-6 to C-23. The results showed a high degree of similarity between the chemical profiles of catalytic pyrolysis products and gasoline.