Optimization of direct conversion of wet algae to biodiesel under supercritical methanol conditions.
This study demonstrated a one-step process for direct liquefaction and conversion of wet algal biomass containing about 90% of water to biodiesel under supercritical methanol conditions. This one-step process enables simultaneous extraction and transesterification of wet algal biomass. The process conditions are milder than those required for pyrolysis and prevent the formation of by-products. In the proposed process, fatty acid methyl esters (FAMEs) can be produced from polar phospholipids, free fatty acids, and triglycerides. A response surface methodology (RSM) was used to analyze the influence of the three process variables, namely, the wet algae to methanol (wt./vol.) ratio, the reaction temperature, and the reaction time, on the FAMEs conversion. Algal biodiesel samples were analyzed by ATR-FTIR and GC-MS. Based on the experimental analysis and RSM study, optimal conditions for this process are reported as: wet algae to methanol (wt./vol.) ratio of around 1:9, reaction temperature and time of about 255 °C, and 25 min respectively. This single-step process can potentially be an energy efficient and economical route for algal biodiesel production.
Patil
Prafulla D
PD
Chemical Engineering Department, New Mexico State University, Las Cruces, NM 88003, USA.
Gude
Veera Gnaneswar
VG
Mannarswamy
Aravind
A
Deng
Shuguang
S
Cooke
Peter
P
Munson-McGee
Stuart
S
Rhodes
Isaac
I
Lammers
Pete
P
Nirmalakhandan
Nagamany
N
D056804:Biofuels; D018533:Biomass; D004951:Esterification; D005227:Fatty Acids / Q000032:analysis / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D000432:Methanol / Q000138:chemical synthesis* / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013997:Time Factors; D014280:Triglycerides / Q000378:metabolism; D014867:Water / Q000378:metabolism*
D056804:Biofuels; D005227:Fatty Acids; D014280:Triglycerides; D014867:Water; D000432:Methanol