Additives initiate selective production of chemicals from biomass pyrolysis

To improve chemicals selectivity under low temperature, a new method that involves the injection of additives into biomass pyrolysis is introduced. This method allows biomass pyrolysis to achieve high selectivity to chemicals under low temperature (300 °C), while nothing was obtained in typical pyrolysis under 300 °C. However, by using the new method, the first liquid drop emerged at the interval between 140 °C and 240 °C. Adding methanol to mushroom scrap pyrolysis obtained high selectivity to acetic acid (98.33%), while adding ethyl acetate gained selectivity to methanol (65.77%) in bagasse pyrolysis and to acetone (72.51%) in corncob pyrolysis. Apart from basic chemicals, one high value-added chemical (2,3-dihydrobenzofuran) was also detected, which obtained the highest selectivity (10.33%) in corncob pyrolysis through the addition of ethyl acetate. Comparison of HZSM-5 and CaCO3 catalysis showed that benzene emerged in the liquid because of the larger degree of cracking and hydrodeoxygenation over HZSM-5.