Oxidative torrefaction performance of microalga Nannochloropsis Oceanica towards an upgraded microalgal solid biofuel

Zhang C 1 , Ho SH 2 , Chen WH 3 , Wang R 1 , Show PL 4 , Ong HC 5

Affiliations 

  • 1 State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China
  • 2 State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China. Electronic address: stephen6949@hit.edu.cn
  • 3 Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, 701, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, 407, Taiwan; Department of Mechanical Engineering, National Chin-Yi University of Technology, Taichung, 411, Taiwan. Electronic address: weihsinchen@gmail.com
  • 4 Department of Chemical and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia, Jalan Broga, Semenyih, 43500, Selangor Darul Ehsan, Malaysia
  • 5 School of Information, Systems and Modelling, Faculty of Engineering and Information Technology, University of Technology Sydney, NSW, 2007, Australia
J Biotechnol, 2021 Sep 10;338:81-90.
PMID: 34298023 DOI: 10.1016/j.jbiotec.2021.07.009

Abstract

Microalgae are a promising feedstock for carbon-neutral biofuel production due to their superior cellular composition. Alternatively, oxidative torrefaction has been recognized as a potential thermochemical technique for microalgal solid biofuel upgrading. Herein, by using microalga N. oceanica as a feedstock, several characterizations are adopted for evaluating the potential of oxidative torrefaction towards microalgal solid biofuel production. The oxidatively torrefied microalgae can be upgraded as lignite. After in-depth analysis, significant change in the surface microstructure of oxidatively torrefied microalgae is largely changed (via wrinkle and fragmentation) The hydrophobicity, thermal decomposition, thermal stability, and aromatization of oxidatively torrefied microalgae can be largely enhanced as the oxidative torrefaction severity increase. With the increasing torrefaction temperature, the hydrophobicity of oxidative torrefied microalgae gradually improved. The decomposition of C-2/3/5, and -OCH3, the CO bonds of CH3CO-, and the aromatization occurs via oxidative torrefaction according to the NMR analysis. For XPS analysis, torrefaction operation significantly decreases the carbide carbon and enhances the graphitization. As a result, the thermal stability of oxidatively torrefied microalgae is improved. Conclusively, the information obtained in this study can provide insights into the evaluation of oxidative torrefaction performance and fuel properties of microalgal solid biofuel, which may help accelerate the advancement of oxidative torrefaction industrialization.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

MeSH terms
Similar publications