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Title: Extraction of Bio-oils from Microalgae

Abstract

A wide variety of terrestrial biomass feed stocks have been identified as suitable candidates for fractionation and conversion into biofuels. In particular, microalgae have been promoted as a future source of transportation fuels primarily because of their stated potential to produce up to 10 times more oil per acre than traditional biofuel crops. Their ability to grow relatively fast, be harvested on a daily basis, and grown in earthen ponds or closed photobioreactors that occupy marginal or poor crop lands using salt or brackish water, are often referenced. When these attractive traits are coupled with the potential to concomitantly harvest valuable co-products such as biopolymers, proteins, and animal feeds, one can see why microalgae are often touted as biotechnology's “green gold”. The development of large-scale microalgae farms, however, has been slowed by limitations in downstream processing technology. For example, traditional methods to dewater, extract, and recover bio-oil from oil-seeds possess little utility for microalgae. The extreme requirement of dewatering poses tremendous hurdles for any technology processing biofuels from microalgae. To further complicate matters, identifying the most appropriate paths for appropriate extraction technology depends heavily on the microalgal species and its cultivation status, both of which are highly characterized for highermore » plants as compared to microalgae. In this review we discuss existing extraction methodologies as they have and can be applied to microalgae. Commentary is provided on their potential as a unit operation that exists within the framework of an industrial-scale microalgal cultivation process that extends from the production of biomass in photobioreactors to the fractionation of the recovered bio-oil.« less

Authors:
; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1252864
Report Number(s):
NREL/JA-510-47587
Journal ID: ISSN 1542-2119
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: Separation and Purification Reviews; Journal Volume: 38; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; bio-oils; microalgae; feed stock; algal biomass

Citation Formats

Cooney, Michael, Young, Greg, and Nagle, Nick. Extraction of Bio-oils from Microalgae. United States: N. p., 2009. Web. doi:10.1080/15422110903327919.
Cooney, Michael, Young, Greg, & Nagle, Nick. Extraction of Bio-oils from Microalgae. United States. doi:10.1080/15422110903327919.
Cooney, Michael, Young, Greg, and Nagle, Nick. 2009. "Extraction of Bio-oils from Microalgae". United States. doi:10.1080/15422110903327919.
@article{osti_1252864,
title = {Extraction of Bio-oils from Microalgae},
author = {Cooney, Michael and Young, Greg and Nagle, Nick},
abstractNote = {A wide variety of terrestrial biomass feed stocks have been identified as suitable candidates for fractionation and conversion into biofuels. In particular, microalgae have been promoted as a future source of transportation fuels primarily because of their stated potential to produce up to 10 times more oil per acre than traditional biofuel crops. Their ability to grow relatively fast, be harvested on a daily basis, and grown in earthen ponds or closed photobioreactors that occupy marginal or poor crop lands using salt or brackish water, are often referenced. When these attractive traits are coupled with the potential to concomitantly harvest valuable co-products such as biopolymers, proteins, and animal feeds, one can see why microalgae are often touted as biotechnology's “green gold”. The development of large-scale microalgae farms, however, has been slowed by limitations in downstream processing technology. For example, traditional methods to dewater, extract, and recover bio-oil from oil-seeds possess little utility for microalgae. The extreme requirement of dewatering poses tremendous hurdles for any technology processing biofuels from microalgae. To further complicate matters, identifying the most appropriate paths for appropriate extraction technology depends heavily on the microalgal species and its cultivation status, both of which are highly characterized for higher plants as compared to microalgae. In this review we discuss existing extraction methodologies as they have and can be applied to microalgae. Commentary is provided on their potential as a unit operation that exists within the framework of an industrial-scale microalgal cultivation process that extends from the production of biomass in photobioreactors to the fractionation of the recovered bio-oil.},
doi = {10.1080/15422110903327919},
journal = {Separation and Purification Reviews},
number = 4,
volume = 38,
place = {United States},
year = 2009,
month =
}
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