A research team developed an acid–metal bifunctional catalyst made from discarded fish bones that efficiently converted waste agricultural film into olefin-rich bio-oil through microwave-assisted pyrolysis. Under optimized conditions, the catalyst produced a bio-oil yield of 89.32 wt.%, with olefins accounting for 84.03% of the oil and C6–C12 compounds dominating the hydrocarbon fraction. By simultaneously valorizing fish-processing residues and difficult-to-recycle plastic mulch, the approach could support more economical plastic recycling and provide a sustainable route to high-value hydrocarbon feedstocks.
Low-density polyethylene mulch film is widely used to conserve soil moisture, regulate temperature, suppress weeds, and improve agricultural productivity. However, residual films can accumulate in soil, generate microplastics, and cause persistent environmental pollution. Pyrolysis can recover their carbon and hydrogen as fuels or chemicals, but conventional thermal processes often require high temperatures and produce poorly controlled mixtures of gases, oils, waxes, and coke. Although acidic and metal-supported catalysts can improve plastic cracking, simultaneously achieving high liquid yields, strong olefin selectivity, low coke formation, and catalyst stability remains challenging. Low-cost catalyst supports derived from biological waste may offer a solution, but the combined effects of acid modification and metal loading require further investigation.
A study (DOI: 10.48130/scm-0026-0021 ) published in Sustainable Carbon Materials on 30 June 2026 by Yunfeng Zhao's team, Shihezi University, reports that a phosphoric-acid-treated, iron-loaded fishbone catalyst enabled high bio-oil production and selective formation of light olefins.
