PAPER REVIEW
Evaluation of the potential of 10 microalgal strains for biodiesel
production
Name: Vijendren Krishnan
Supervisor: Prof. Dr. Yoshimitsu Uemura
In this study, the potential of 10 algae species for biodiesel production
were evaluated by determining their fatty acid profiles, biodiesel
properties besides growth rate, biomass concentration and lipid
productivity. Among seven strains with high growth and lipid
accumulation properties, excluding Kirchneriella lunaris and Lyngbya
kuetzingii, five species Selenastrum capricornutum, Chlorella vulgaris,
Scenedesmus obliqnus, Phaeodactylum tricornutum and Isochrysis
sphacrica were finally selected for biodiesel production due to their
possessing higher lipid productivity and favorable biodiesel properties.
The best strain was P. tricornutum, with lipid content of 61.43 ± 0.95%,
lipid productivity of 26.75 mg L1 d1, the favorable fatty acid profiles of
C16–C18 (74.50%), C14:0 (11.68%) and C16:1 (22.34%) as well as
suitable biodiesel properties of higher cetane number (55.10), lower
iodine number (99.2 gI2/100 g) and relatively low cloud point (4.47 C).
Introduction
• Microalgae posses high qualities such as rapidbiomass concentration, high lipid content, tolerant toextreme environment.
• Utilization of microalgae for biodiesel production isalso cost effective and environmental friendly.
• FA chain length and degree of unsaturation in FAMEinfluence:
* Kinematic viscocity * cloud point
* Specific gravity * iodine value
* Cetane number * Higher heating value
• FA chain length & degree of unsaturation in FAMEdetermine fuel properties:
• CN, Vis and CP increases with increasing chain length
• CN, Vis and CP decreases with increasing degree ofunsaturation
• SG, IV and HHV increases with increasing degree ofunsaturation
• SG, IV and HHV decreases with increasing chainlength
• Long chain length and low degree of unsaturation arepreferable biodiesel to get low temp performance andgood oxidative stability.
Objective
• To determine if common algae species in localwater system had the potential to accumulate lipidby assesing their growth and oil yield properties.
MethodologyCultivated in single batch 500ml for 15days.
Growth rate determined by Neubauerhaem
ocytometer slide every 2 days.
K = (lnN – lnN0)/ (t-t0)
Biomass DW determination
Total lipid extraction
FA profile analyses
Total Lipid extraction100mg dried algal transferred into 5 ml (CCl4/MeOH; 2:1)
Homogenized for 10min in ultrasonic homogenizer
Supernatant was collected in a separation funnel
Extraction was repeated twice.
Centrifuged at 4000rpm at 12oC for 10min
NaCl (0.9 v/v) added at proportion 1:5 v/v of lipid extract
Extract was shaken vigorously for 1min and allowed to
undergo phase separation for 15min
Organic solvent was dried off from the lower phase using
Nitrogen evaporator
Result
Conclusion
The best strain was P. tricornutum, with lipidcontent of 61.43 ± 0.95%, lipid productivityof 26.75 mg L1 d1, the favorable FA profilesof C16–C18 (74.50%) and C16:1 (22.34%)as well as suitable biodiesel properties ofhigher cetane number (55.10), lower iodinenumber (99.2 gI2/100 g) and relative lowcloud point (4.47 C).