Characterization of biofuel from diatoms via hydrothermal liquefaction

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.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Agricultural & Biological Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Zhang, Peng

Contributors dc:contributor

• Zhang, Yuanhui

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

Statement dc:rights

• Copyright 2014 Peng Zhang

Language dc:language

en

Handle dc:identifier

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

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/50657