Characterization of biofuel from diatoms via hydrothermal liquefaction

Zhang, Peng

Permalink

https://hdl.handle.net/2142/50657 Copy

Description

Title

Characterization of biofuel from diatoms via hydrothermal liquefaction

Author(s)

Zhang, Peng

Issue Date

2014-09-16

Director of Research (if dissertation) or Advisor (if thesis)

Zhang, Yuanhui

Department of Study

Engineering Administration

Discipline

Agricultural & Biological Engr

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Bio-crude oil
• Hydrothermal
• Liquefaction
• microalgae
• diatoms
• frustule

Abstract

Previous studies of hydrothermal liquefaction (HTL) converting low lipid content microalgae (i.e., Chlorella pyrenoidosa and Spirulina platensis) have shown potential to utilize low lipid microalgae to produce bio-crude oil. Diatoms are a major group of microalgae in water bodies with a high growth rate and that contribute about 20% of global primary production. Their unique frustule (silica cell wall) results in a high ash content (39% dry weight). This character makes the bio crude oil absorbed in solid product after hydrothermal liquefaction, rather than viscous liquid product as we have seen from C. pyrenoidosa and S. platensis. Most of the organic matter in the diatom biomass was converted into alkanes, fatty acyls, and small fractions of undesirable nitrogen-containing compounds, such as pyrazines, according to GC-MS analysis. The inorganic frustules remained in the solid residue, unchanged after the hydrothermal process, with small amounts of organic matter attached, as revealed by SEM observation and FT-IR characterization. The higher alkane content indicated competitive quality of bio crude oil from diatoms to those from C. pyrenoidosa and S. platensis. However, challenges arise along with the high amount of solid residue, which may cause extra difficulty for product separation and reactor design.

Graduation Semester

2014-08

Permalink

http://hdl.handle.net/2142/50657

Copyright and License Information

Copyright 2014 Peng Zhang

Owning Collections