Selective fungal pretreatment favored pyrolysis products of wheat straw based on pyrolytic polygeneration system

A novel wheat straw valorization strategy was developed in which selective fungal pretreatment was applied to promote pyrolytic polygeneration from wheat straw using a fixed-bed reactor. Selective delignification of wheat straw by Pleurotus ostreatus was confirmed. Kinetic analysis based on a modified three-parallel-reaction model indicated that thermally resistant lignin structures were converted to easily degradable structures during fungal pretreatment, facilitating the pyrolysis of wheat straw. The effects of the selective fungal pretreatment on the profiles of pyrolytic products (bio-oil, biogas and biochar) were clearly illustrated. After selective fungal pretreatment, the bio-oil yield increased by 51.09%, and the yields of some high value-added products, such as isosorbide, greatly increased. Moreover, the biochar produced by pyrolysis from the selective fungus-treated wheat straw had characteristics for the adsorption of dyes and pollutants. Therefore, selective delignification by fungal pretreatment increased the thermochemical conversion efficiency during pyrolytic polygeneration from wheat straw.