Microwave catalytic co-pyrolysis of low-density polyethylene and spent bleaching clay for monocyclic aromatic hydrocarbons

Abstract

Combined with the fact that the poor heat transfer effect of low-density polyethylene (LDPE), the microwave absorption characteristics of spent bleaching clay (SBC) and the synergistic effect of co-pyrolysis, we conducted a study. In this study, microwave-assisted catalytic co-pyrolysis of SBC and LDPE was used to produce bio-oil rich in monocyclic aromatic hydrocarbons (MAHs). Then the conditions of co-pyrolysis, including pyrolysis temperature, catalytic temperature, the ratio of SBC/LDPE and catalytic mass were explored. The findings revealed that SBC and LDPE had a synergistic effect, SBC had microwave absorption characteristics, which could transfer heat to LDPE to improve heating rate. And the high H/Ceff of LDPE promoted the deoxidation of the SBC, which could optimize the quality of bio-oil. Compared with 43.69% for LDPE pyrolysis alone and 47.18% for SBC pyrolysis alone, the content of MAHs during co-pyrolysis was 54.92%. The optimum pyrolysis parameter was discovered at the pyrolysis temperature of 550 °C, 450 °C of catalytic temperature, 40:28.5 ratio of SBC to LDPE, 7 g of HZSM-5 mass, 69.89% of MAHs and 16.48% of Polycyclic aromatic hydrocarbons was obtained.