Fractionation biomass pyrolysis

Gayubo, A.G., Aguayo, A.T., Atutxa, A., Prieto, R., Bilbao, J., Deactivation of a HZSM-5 zeolite catalyst in the transformation of the aqueous fraction of biomass pyrolysis oil into hydrocarbons, Energy Fuels, 2004, 18, 1640. 

Biomass includes 60% wood and 40% non-wood materials. The conversion of wood into biofuels andbiochemicals is technically feasible. Wood valorization processes include fractionation, liquefaction, pyrolysis, hydrolysis, fermentation and gasification. 

Pyrolysis oil (bio-oil) is produced in fast and flash pyrolysis processes and can be used for indirect co-firing for power production in conventional power plants and potentially as a high energy density intermediate for the final production of chemicals and/or transportation fuels. Gas chromatographic analysis of the liqtrid fraction of pyrolysis products from beech wood is given in Table 3.6 (Demirbas, 2007). Biocmde resrrlts from severe hydrothermal upgrading (HTU) of relatively wet biomass and potentially can be used for the production of materials, chemicals,... 

Pakdel H, Munvanashyaka J N, Roy C, Fractional vacuum pyrolysis of biomass for high yields of phenolic compounds . These proceedings Hinunelblau A Combined chemicals and energy production from biomass pyrolysis , These proceedings... 

Statistical manipulations on the USDA database (cluster analysis, principal component analysis with varimax rotation e.g., Everitt, 1980) revealed subsets of represent ve species, as idealized in Fig 2b, but with dif ent variables (orthogonal principal components) than traditional fractions as measured by USDA. A set cf species from each orthogonal subset appears in Table 1. The Latin names, and where available, the common names of the biomass species are given. The extractives ranges are ash content, 4 to 17% protein content, 5 to 14% polyphenol, 3 to 11% and oil content, 1 to 4%. However no species contains extremes of all 4 variables. Nor can species be found, retaining native compositions, at extremes of just one extractive composition, while the other fractions are present at constant levels. Thus we use orthogonal but non-intuitive compositions in this work, then rank pyrolysis effects in terms of traditional extractives content to get an understanding of their impact on biomass pyrolysis. 

Obtained data show that, the mixtures of the different types of the natural and synthetic organic polymers can be successfully converted with a high yield to light distillate fraction by pyrolysis under inert atmosphere and catalytic hydtopyrolysis in the autoclave conditions. The optimum tenqreiature of biomass / plastic mixtures conveision which coiresponds to the maximum yield of liquids is 390 - 400 C. In the CO liquefaction processes the interaction between products of natural and synthetic polymers thermal deconqwsition takes place. 

Fractional Vacuum Pyrolysis of Biomass for High Yields of Phenolic Compounds... 

Many biomass pyrolysis processes convert 55%-65% of dry biomass to a very inexpensive pyrolysis oil (1-3). Costs of the oils will range from 0.02- 0.08/lb of oil, depending on the biomass feedstock cost ( 10- 40/dry ton biomass). Therefore, these inexpensive oils, rich in phenolic fractions, acids, and furan-derivatives could be feedstocks for further upgrading or could be used because of their reactivity, in applications such as thermosetting resins and other wood-bonding methods. One of the... 

The identification and extraction of valuable chemicals from wood-derived oils is a very important goal for the biomass thermochemical conversion industry (lz2). Pyrolysis oils have been extensively studied and extensive number of compounds have been identified (3-4). However to our knowledge there are only two general methods which have been reported for the fractionation of pyrolysis oils... 

Murwanashyaka JN, Pakdel H, Roy C. Fractional vacuum pyrolysis of biomass and separation of phe-nohc compounds by steam distillation. In Bridgwater AV, editor. Fast pyrolysis of biomass a handbook volume 2. UK CPL Press 2002. p. 407—18. 

A high aromatics selectivity, however, requires proper catalyst selection. Zhang et al. studied the fast pyrolysis of corncob in absence and presence of a catalyst (ie, ZSM-5) [287]. The presence of the catalyst increased the yields of noncondensable gas, water, and coke, while decreasing the liquid and char yields. The catalyst induced a decrease of the oxygen content of the liquid fraction by more than 25%. These studies indicate the importance of a catalyst during biomass pyrolysis. The most important catalytic parameters affecting the product distribution are pore structure and acid site type. This was demonstrated by testing siUcalite, a material with the same pore structure as ZSM-5 but with intrinsic different acid sites, and siUca-alumina, an amorphous material with Brpnsted acid sites, in the catalytic pyrolysis of... 

Pyrolysis has a long history in the upgrading of biomass. The dry distillation of hardwood was applied in the early 1990s to produce organic intermediates (methanol and acetic acid), charcoal and fuel gas [3]. Today s processes can be tuned to form char, oil and/or gas, all depending on the temperature and reaction time, from 300 °C and hours, to 400-500 °C and seconds-minutes, to >700 °C and a fraction of a second [3, 19, 23, 24], The process is typically carried out under inert atmosphere. We illustrate the basic chemistry of pyrolysis by focusing on the conversion of the carbohydrate components (Fig. 2.4). The reaction of the lignin will not be covered here but should obviously be considered in a real process. Interested readers could consult the literature, e.g., [25]. Pyrolysis is discussed in more details elsewhere in this book [26],... 

CO = 25 vol.%, C02 = 12 vol.%) not containing any hydrocarbons and a low tar (200 mg Nm 3) content at 800 °C and S/C (steam over carbon ratio) = 1.5. Problems associated with pyrolysis oil gasification are similar to those of biomass gasification. Gasification of the tar fraction and conversion of methane formed are important challenges. Both require highly active and stable steam/autothermal reforming catalysts. 

M. Mann, E. Chorlet, in Hydrogen production via catalytic steam reforming of fast pyrolysis oil fractions. Proceedings of the 3ri Biomass Conference of the Americas, Pergamon, Oxford, 1997, p. 845. 

Wang, D., Czernik, S., Montane, D., Mann, M., Chornet, E. 1997. Biomass to hydrogen via fast pyrolysis and catalytic steam reforming of the pyrolysis oil or its fractions. Ind Eng Chem Res 36 1507-1518. 

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