Conversion of waste mask into hydrocarbon-rich fuels through catalytic pyrolysis with Zr-Mg bimetallic catalyst under N2/CO2 atmosphere

In this work, the Zr-Mg bimetallic catalyst is prepared and used to facilitate the conversion of the waste mask to hydrocarbon-rich fuels. The effects of the catalyst and the reaction atmosphere on pyrolysis behaviors of different layers of the mask are discussed, and the interactions between CO2 and the catalyst are analyzed. The results showed that the synthesized catalyst significantly promoted the conversion of long-chain hydrocarbons to short-chain hydrocarbons. Compared with pyrolysis alone under N2 atmosphere, the relative contents of hydrocarbon compounds obtained by catalytic pyrolysis in the inner layer and middle layer increased by 12.21% and 16.24%, respectively. Additionally, the relative content of olefins in the liquid product increased by 9.62%. When the pyrolysis atmosphere was changed from N2 to CO2, the selectivity of the cycloalkanes was significantly enhanced. Also, the interactions between CO2 and the catalyst improved the selectivity of C2H6. These works provide important support for the effective disposal of masks and an in-depth understanding of the CO2-assisted pyrolysis process.