Catalytic fast pyrolysis of mushroom waste to upgraded bio-oil products via pre-coked modified HZSM-5 catalyst

In this paper, HZSM-5 catalyst was modified by pre-coked to cover the strong external acid sites by methanol to olefins reaction, and the modified catalysts were then applied to conduct the catalyst fast pyrolysis of mushroom waste for upgraded bio-fuel production. Experiment results showed that the strong external acid sites and specific surface area decreased with pre-coked percentage increasing from 0% to 5.4%. Carbon yields of hydrocarbons increased at first and then decreased with a maximum value of 53.47%. While the obtained oxygenates presented an opposite variation tendency, and the minimum values could be reached when pre-coked percentage was 2.7%. Among the achieved hydrocarbons, toluene and p-xylene were found to be the main products, and the selectivity of p-xylene increased at first and then decreased with a maximum value of 34.22% when the pre-coked percentage was 1.3%, and the selectivity of toluene showed the opposite tendency with a minimum value of 25.47%.