Ceria on alumina support for catalytic pyrolysis of Pavlova sp microalgae to high-quality bio-oils

In this work, we report for the first time the in-situ catalytic pyrolysis of Pavlova sp. microalgae, which has been performed in a fixed-bed reactor in presence of Ce/Al2O3-based catalysts. The effects of pyrolysis parameters, such as temperature and catalyst were studied on the products yield distribution and bio-oil composition, among others. Results showed that all catalysts increased the bio-oil yield with respect to the non-catalytic runs and reduced the O/C ratio from 0.69 (Pavlova sp.) to 0.1-0.15, which is close to that of crude oil. In terms of bio-oil oxygen content, MgCe/Al2O3 presented the best performance with a reduction of more than 30%, from 14.1 to 9.8 wt%, of the oxygen concentration in comparison with thermal pyrolysis. However, NiCe/Al2O3 gave rise to the highest aliphatics/aromatics fractions. The elemental and gas analysis indicates that N was partially removed from the catalytic bio-oils in the gas phase in forms of NH3 and HCN. (C) 2017 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.