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Effect of the storage condition of microalgae on hydrochar lipids and direct esterification-transesterification of hydrochar lipids for biodiesel production

Yoshikawa Laboratory, Department of Environmental Science and Technology, Tokyo Institute of Technology, Yokohama, Kanagawa, 226-8502, Japan

Topical Section: Bioenergy and Biofuel

The hydrochar product from the hydrothermal carbonization (HTC) of microalgae contains most of fatty acids (FAs) in the original microalgae. In the hydrochar, FAs exist in both types of bound fatty acids (BFAs) and free fatty acids (FFAs). Besides, when the microalgae paste is stored at the room temperature (25 °C) for one day, there is an increase of total fatty acids (TFAs) and free fatty acids (FFAs) in microalgae. The hydrochar from this microalgae paste was proved to have a higher amount of TFAs and a higher percentage of FFAs/TFAs compared to the ordinary hydrochar (without the additional storage step) in this research. Both of these factors favor for the subsequent acid catalyzed esterification-transesterification reaction of hydrochar lipids. In summary, a process based on a combination of the storage of fresh microalgae, the HTC of microalgae paste, and the direct esterification-transesterification of the hydrochar has been developed for biodiesel production. With the additional storage step of fresh microalgae, the total biodiesel yield has been improved of 19.3% in the optimum condition.
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1. Mata TM, Martins AA, Caetano NS (2010) Microalgae for biodiesel production and other applications: a review. Renew Sust Energ Rev 14: 217-232.

2. Heilmann SM, Davis HT, Jader LR, et al. (2010) Hydrothermal carbonization of microalgae. Biomass Bioenerg 34: 875-882.    

3. Heilmann SM, Jader LR, Harned LA, et al. (2011) Hydrothermal carbonization of microalgae II. Fatty acid, char, and algal nutrient products. Appl Energ 88: 3286-3290.

4. Garcia Alba L, Torri C, Samorì C, et al. (2011) Hydrothermal treatment (HTT) of microalgae: evaluation of the process as conversion method in an algae biorefinery concept. Energ Fuel 26: 642-657.

5. Levine RB, Sierra COS, Hockstad R, et al. (2013) The use of hydrothermal carbonization to recycle nutrients in algal biofuel production. Environ Prog Sust Energ 32: 962-975.    

6. Levine RB, Pinnarat T, Savage PE (2010) Biodiesel production from wet algal biomass through in situ lipid hydrolysis and supercritical transesterification. Energ Fuel 24: 5235-5243.

7. Folch J, Lees M, Sloane-Stanley G (1957) A simple method for the isolation and purification of total lipids from animal tissues. J Biol Chem 226: 497-509.

8. Halim R, Gladman B, Danquah MK, et al. (2011) Oil extraction from microalgae for biodiesel production. Bioresource Technol 102: 178-185.

9. Griffiths M, Van Hille R, Harrison S (2010) Selection of direct transesterification as the preferred method for assay of fatty acid content of microalgae. Lipids 45: 1053-1060.    

10. Tran H-L, Hong S-J, Lee C-G (2009) Evaluation of extraction methods for recovery of fatty acids from Botryococcus braunii LB 572 and Synechocystis sp. PCC 6803. Biotechnol Bioprocess Eng 14: 187-192.

11. Lewis T, Nichols PD, McMeekin TA (2000) Evaluation of extraction methods for recovery of fatty acids from lipid-producing microheterotrophs. J Microbiol Meth 43: 107-116.    

12. Chen L, Liu T, Zhang W, et al. (2012) Biodiesel production from algae oil high in free fatty acids by two-step catalytic conversion. Bioresource Technol 111: 208-214.

13. Singh A, Nigam PS, Murphy JD (2011) Mechanism and challenges in commercialisation of algal biofuels. Bioresource Technol 102: 26-34.

14. Khuwijitjaru P, Adachi S, Matsuno R (2002) Solubility of saturated fatty acids in water at elevated temperatures. Biosci Biotechnol Bioch 66: 1723-1726.    

15. Poerschmann J, Weiner B, Wedwitschka H, et al. (2014) Characterization of biocoals and dissolved organic matter phases obtained upon hydrothermal carbonization of brewer’s spent grain. Bioresource Technol 164: 162-169.    

16. Golzary A, Imanian S, Abdoli MA, et al. (2015) A cost-effective strategy for marine microalgae separation by electro-coagulation–flotation process aimed at bio-crude oil production: Optimization and evaluation study. Sep Purif Technol 147: 156-165.    

17. Sanyano N, Chetpattananondh P, Chongkhong S (2013) Coagulation–flocculation of marine Chlorella sp. for biodiesel production. Bioresource Technol 147: 471-476.    

18. Broch A, Jena U, Hoekman SK, et al. (2013) Analysis of solid and aqueous phase products from hydrothermal carbonization of whole and lipid-extracted algae. Energies 7: 62-79.

19. Lu Y, Levine RB, Savage PE (2014) Fatty Acids for Nutraceuticals and Biofuels from Hydrothermal Carbonization of Microalgae. Ind Eng Chem Res 54: 4066-4071.

20. Laurens LM, Quinn M, Van Wychen S, et al. (2012) Accurate and reliable quantification of total microalgal fuel potential as fatty acid methyl esters by in situ transesterification. Anal Bioanal Chem 403: 167-178.    

21. Thenot J-P, Horning E, Stafford M, et al. (1972) Fatty acid esterification with N, N-dimethylformamide dialkyl acetals for GC analysis. Anal Lett 5: 217-223.

22. Dong T, Wang J, Miao C, et al. (2013) Two-step in situ biodiesel production from microalgae with high free fatty acid content. Bioresource Technol 136: 8-15.

23. Al-Zuhair S, Hasan M, Ramachandran K (2003) Kinetics of the enzymatic hydrolysis of palm oil by lipase. Process Biochem 38: 1155-1163.    

24. Khuwijitjaru P, Fujii T, Adachi S, et al. (2004) Kinetics on the hydrolysis of fatty acid esters in subcritical water. Chem Eng J 99: 1-4.    

25. Montaini E, Zittelli GC, Tredici M, et al. (1995) Long-term preservation of Tetraselmis suecica: influence of storage on viability and fatty acid profile. Aquaculture 134: 81-90.    

26. Dubois M, Gilles KA, Hamilton JK, et al. (1956) Colorimetric method for determination of sugars and related substances. Anal Chem 28: 350-356.    

27. Du Z, Mohr M, Ma X, et al. (2012) Hydrothermal pretreatment of microalgae for production of pyrolytic bio-oil with a low nitrogen content. Bioresource Technol 120: 13-18.    

28. Kail BW, Link DD, Morreale BD (2012) Determination of free fatty acids and triglycerides by gas chromatography using selective esterification reactions. J Chromatogr Sci bms093.

29. Perry RH, Green DW (1999) Perry's chemical engineers' handbook: McGraw-Hill Professional.

30. Valdez PJ, Nelson MC, Wang HY, et al. (2012) Hydrothermal liquefaction of Nannochloropsis sp.: Systematic study of process variables and analysis of the product fractions. Biomass Bioenerg 46: 317-331.

31. Christie WW (1993) Preparation of ester derivatives of fatty acids for chromatographic analysis. Adv Lipid Meth 2: e111.

32. Liu Z, Zhang F-S, Wu J (2010) Characterization and application of chars produced from pinewood pyrolysis and hydrothermal treatment. Fuel 89: 510-514.    

33. Kang S, Li X, Fan J, et al. (2012) Characterization of hydrochars produced by hydrothermal carbonization of lignin, cellulose, D-xylose, and wood meal. Ind Eng Chem Res 51: 9023-9031.    

34. Chen Z, Ma L, Li S, et al. (2011) Simple approach to carboxyl-rich materials through low-temperature heat treatment of hydrothermal carbon in air. Appl Surf Sci 257: 8686-8691.

35. Liu Z, Zhang F-S (2009) Removal of lead from water using biochars prepared from hydrothermal liquefaction of biomass. J Hazard Mater 167: 933-939.

Copyright Info: © 2017, Vo Thanh Phuoc, et al., licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

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