(689d) Liquefaction of Low-Lipid Macroalgae for Production of Liquid Fuel

Shicheng Zhang*, Dong Zhou, Changjun Li, Xiao Yang, Jianmin Chen

Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China

*Corresponding author phone: +86-21-65642297; fax: +86-21-65642080; e-mail:

zhangsc@fudan.edu.cn

Low-lipid marine macroalgae Enteromorpha prolifera, one of the main algae genera for green tide, was converted to bio-oil and ester compounds in sub-/supercritical water or alcohols in a batch reactor. Effects of the temperature, reaction time, Na₂CO₃ catalyst, and algae/solvent ratio on the yields of liquefaction products were investigated. The raw algae and liquefaction products were analyzed using elemental analysis, Fourier transform infrared (FTIR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), and 1Hnuclear magnetic resonance (NMR). The bio-oil obtained in water was a complex mixture of ketones, aldehydes, phenols, alkenes, fatty acids, esters, aromatics, and nitrogen containing heterocyclic compounds. And acetic acid was the main component of the water-soluble products. Otherwise, the bio-oils obtained in alcohols were mainly composed of ester compounds. A variety of fatty acid (C3—C22) esters (methyl or ethyl) in the bio-oils respectively obtained in methanol and ethanol were qualified by GC-MS, and their relative contents are above 60% of the total area for each bio-oil. In addition, some N-containing compounds, sugars, fatty alcohols/ketones and very few hydrocarbons were also qualified. Overall, bio-oils obtained in two alcohols are much similar to biodiesel on the composition. Moreover, the bio-oils are found to contain a considerable fraction of light components using thermogravimetric analysis (TGA), and the contents of low-boiling (bp<350 ^oC) compounds are up to 70% of the weight for both bio-oils, therefore, it might help to the further separation and refining of bio-oils to produce fuels and chemicals.

References

1. Dong Zhou, Liang Zhang, Shicheng Zhang, Hongbo Fu, Jianmin Chen. Hydrothermal Liquefaction of Macroalgae Enteromorpha prolifera to Bio-oil. Energy & Fuels. 2010, 24, 4054–4061.
2. Dong Zhou, Shicheng Zhang, Hongbo Fu, Jianmin Chen. Liquefaction of Macroalgae Enteromorpha prolifera in Sub-/Supercritical Alcohols: Direct Production of Ester Compounds. Energy & Fuels. 2012. 26 (4), 2342-2351.