Preparation of highly selective olefins from pyrolyzed ground film plastics catalyzed by fishbone-based catalysts

Ground film plastic, widely used in large-scale agriculture, is a major source of persistent white pollution due to its poor degradability. This work investigates the pyrolysis process of agricultural plastic mulch using a modified fishbone-derived metal catalyst combined with microwave-assisted pyrolysis. Experimental data indicate that the 5Cu/HAP fishbone catalyst exhibits optimal catalytic performance. The ideal pyrolysis conditions are: pyrolysis temperature of 550°C, catalytic temperature of 350°C, and a catalyst-to-feedstock ratio of 1:2. Under these conditions, an 80.30 wt% liquid oil yield was achieved, with maximum olefin selectivity reaching 63.92 % and a 90.80 % selectivity of C6∼C12 olefins. These results demonstrate the significant potential of catalytic pyrolysis using modified fishbone-derived metal catalysts for converting agricultural plastic waste into C6∼C12 olefins. These olefins can be further processed into high-purity chemicals like naphtha and gasoline. As olefins are also essential plastic raw materials, this approach enables a potential closed-loop film-to-olefin-to-film recycling cycle, offering a promising new pathway for the chemical recycling of plastic waste.