title: Hydrothermal liquefaction of microalgae for biocrude production: Improving the biocrude properties with vacuum distillation.
abstract: This paper proposes a two-part process for producing biocrude with reduced impurities. The biocrude was produced from hydrothermal liquefaction (HTL) of Spirulina sp. and Tetraselmis sp. in a batch reactor at both 300 and 350°C, 5min, and 16%w/w solid feed composition. The resultant biocrudes were vacuum distilled at a maximum temperature of 360°C. It was shown that biocrude quality could be enhanced without using catalyst by vacuum distillation (VD). The biocrude yield for Spirulina sp. was 36wt% at 300°C, 42wt% at 350°C, and for Tetraselmis sp. was 34wt% at 300°C, and 58wt% at 350°C. VD of Spirulina sp. biocrude obtained at 300 and 350°C led to 62 and 67wt% distilled biocrudes yield, respectively. VD of Tetraselmis sp. biocrude obtained at 300°C was 70wt%, and 73wt% at 350°C. The higher heating values (HHV) increased from 32MJ/kg to 40MJ/kg. There were substantial reductions in oxygen, metallic content, and boiling point ranges in distilled biocrudes.
authors.affiliation: Microalgal Engineering Research Group, School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia. Electronic address: blessing.eboibi@adelaide.edu.au.
authors.forename: Blessing Elo-Oghene
authors.initials: BE
authors.lastname: Eboibi
authors.affiliation: Microalgal Engineering Research Group, School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia; Muradel Pty Ltd, Maylands, South Australia 5069, Australia.
authors.forename: David Milton
authors.initials: DM
authors.lastname: Lewis
authors.affiliation: Microalgal Engineering Research Group, School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia.
authors.forename: Peter John
authors.initials: PJ
authors.lastname: Ashman
authors.affiliation: Biotechnology Division, Aban Infrastructure Pvt. Ltd, Chennai 600 008, Tamil Nadu, India.
authors.forename: Senthil
authors.initials: S
authors.lastname: Chinnasamy
mesh_terms: D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000032:analysis; D005591:Chemical Fractionation; D000460:Chlorophyta / Q000187:drug effects / Q000378:metabolism; D003116:Color; D045424:Complex Mixtures; D057168:Distillation / Q000379:methods*; D004734:Energy Metabolism / Q000187:drug effects; D006859:Hydrogen / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000032:analysis; D058086:Microalgae / Q000187:drug effects / Q000378:metabolism*; D009584:Nitrogen / Q000032:analysis; D013696:Temperature; D014618:Vacuum; D014867:Water / Q000494:pharmacology*
chemical_list: D045424:Complex Mixtures; D008670:Metals; D014867:Water; D002244:Carbon; D006859:Hydrogen; D009584:Nitrogen
keywords: Biocrude; Distilled biocrude; Hydrothermal liquefaction; Microalgae