Catalytic pyrolysis of chemical extraction residue from microalgae biomass

Pyrolysis characteristics of chemical extraction microalgae residue in the presence and absence of catalysts (KCl, KOH, K2CO3, Al2O3, CaO, MgO and pyrolysis char of microalgae residue) were evaluated using a thermal analyzer and a tube furnace reactor. These catalysts can effectively improve the oil yield during microalgae residue pyrolysis. The order of the strength on increasing the oil yield was: pyrolysis char of microalgae residue > Al2O3>CaO > K2CO3>MgO > KCl > KOH. The addition of all the catalysts can effectively reduce the potential ecological risk of heavy metals in pyrolysis chars. The addition of KCl, MgO and Al2O3 can increase the content of gasoline components in pyrolysis oil. All the catalysts can reduce the content of CO2 in the pyrolysis gas, and increase the content of CO and hydrocarbon gases. KCl addition showed considerable increase in both yield and quality of pyrolysis oil and gas with a proportion of 5 wt % during microalgae residue pyrolysis. (C) 2019 Elsevier Ltd. All rights reserved.