Upgrading of Bio-Oil

The quality of bio-oil can be improved by applying physical or chemical (in particular, catalytic) methods. In this section, we focus on the catalytic upgrading of bio-oil. 

The quality of the highly oxygenated bio-oil can be improved by deoxygenation through various methods. The most common ones reported in the literature are 

Zeolites, which are crystalline aluminosilicate minerals having a three-dimensional microporous (smaller than 2 nm) framework structure, are widely used in many applications in the oil-refining industry as catalysts [31]. Mesoporous materials have similar properties as zeolites, but the pore size is larger than 2 nm. 

The required hydrogen needed for the hydrogenation of bio-oil can be produced through steam reforming of bio-oil over Ni-supported alumina catalysts [32], Hydrogen yields as high as 73% could be produced at 950°C without a low-temperature water-gas shift reactor [32], 

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Catalytic upgrading of bio-oil was carried out over Ga modified ZSM-5 for the pyrolysis of sawdust in a bubbling fluidized bed reactor. Effect of gas velocity (Uo/U ,f) on the yield of pyrolysis products was investigated. The maximum yield of oil products was found to be about 60% at the Uo/Umf of 4.0. The yield of gas was increased as catalyst added. HZSM-5 shows the larger gas yield than Ga/HZSM-5. When bio-oil was upgraded with HZSM-5 or Ga/HZSM-5, the amount of aromatics in product increased. Product yields over Ga/HZSM-5 shows higher amount of aromatic components such as benzene, toluene, xylene (BTX) than HZSM-5. 

Czemik S. (1999) Workshop on stabilisation /upgrading of bio-oils. Pyrolysis Network. Vacuum Pyrolysis, 8, 3. 

Meier D., Wehlte S., Wulzinger P. Faix O. (1996) Upgrading of bio-oils and flash pyrolysis of CCB-treated wood waste. In Bio-oil Production and Utilization-Proceedings of the 2nd EU-Canada Workshop on Thermal Processing. (Ed. by Bridgwater AV Boocock DGB) CPL Press, UK, pp. 1402-1412... 

Mortraiscai PM, Grunwaldt J-D, Jensen PA, Knudsen KG, Jensen AD (2011) A review of catalytic upgrading of bio-oil to caigine fuels. Appl Catal A Gen 407 1—19... 

The generated H2 can be converted to liquid fuels through Fischer-TLopsch reactions, or used in the upgrading of bio-oils. 

Upgrading of Bio-Oils Obtained from Biomass Pyrolysis with Alumina and... 

To begin, we discuss the upgrading of bio-oils by means of cracking and hydrodeoxygenatioa This will be followed by upgrading pyrolysis vapors and cataljdic pyrolysis. Finally, a short overview of catalytic fast pyrolysis of lignin will close this part of the chapter. 

Keller, T.C., Rodrigues, E.G., Perez-Ramfrez, J., 2014. Generation of basic centers in high-siUca zeolites and their application in gas-phase upgrading of bio-oil. ChemSusChem 7 (6), 1729-1738. 

Yu, W., Tang, Y., Mo, L., Chen, P., Lou, H., Zheng, X., 2011b. Bifunctional Pd/Al-SBA-15 catalyzed one step hydrogenation-esterification of furfural and acetic acid a model reaction for catalytic upgrading of bio-oil. Catalysis Communications 13 (1), 35—39. 

Chaiwat, W., Gunawan, R., Gholizadeh, M., Li, X., Lievens, C., Hu, X., Wang, Y., Mourant, D., Rossiter, A., Bromly, J., Li, C.-Z., 2013. Upgrading of bio-oil into advanced biofuels and chemicals. Part II. Importance of holdup of heavy species during the hydrotreatment of biooil in a continuous packed-bed catalytic reactor. Fuel 112, 302—310. 

Zacher, A.H., Elliott, D.C., Olarte, M.V., Santosa, D.M., Preto, F., lisa, K., 2014. Pyrolysis of woody residue feedstocks upgrading of bio-oils from mountain-pine-beetle-killed trees and hog fuel. Energy Fuels 28, 7510—7516. 

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